Wednesday, 19th April 2000 (10.30 am)
THE CHAIRMAN: Good morning and welcome to the second seminar in this series. We had a good discussion yesterday and I hope we will be able to have another good discussion today. We are grateful for both the draft reports. I would like to follow the same pattern as yesterday which is to invite both teams to introduce their papers. Then we will have a brief period for questions of fact and clarification. I will then invite other people sitting at the table to make any introductory remarks on both papers that they want to make. Hopefully, out of that process a number of issues will present themselves for further discussion and to provide our agenda for the rest of the day. If I could just give one reminder to everyone: our remit is to focus on facts and analysis. We do not have to make a recommendation about whether or not hunting should be banned. Our focus is, therefore, very much upon the evidence and what it can tell us. If the evidence is inconclusive, it is also helpful to know that. I mention it merely because in a session when there is going to be a great deal to discuss, we should be wanting to try and focus as much as possible on what it is that we can say and what it is that we cannot say about this very complicated subject. I think, David, you are going to do the first presentation and then Stephen Harris will do the second presentation. Thank you very much.
PROFESSOR MACDONALD: Can I check that I am audible. My Lords, ladies and gentlemen, speakers obviously are always enthusiastic to win the sympathy of those to whom they are speaking and I am no exception, so let me begin by telling you that you have, Committee, posed to us a series of questions. I think there is about six of them for four groups of species and it concerned at least four interest groups, which means you are expecting in the course of this morning 96 answers, at the very least, and by my calculation that gives me 12 and a half seconds per answer or 4 seconds per page of the report. The good news is that I do not have to climb that mountain alone because I have with me the team of people that helped compile the report and so my intention is to provide this overview myself, but when it comes to questions we will be sharing the load amongst us. I should also add that the matrix of questions and species and interest groups with which we have to deal is made yet more complicated and multidimensional by the fact that the answers to many of the questions have a regional basis and many of the interest groups contain more than one faction, adding to the complexity. For that reason, I am going to try and make sure that the talk focuses on the sort of data we have been able to uncover rather than providing you with abundant background information of actually what happens when hunting is going on, because I rather assume people know about that. Let me begin by summarising for you the questions -- I hope with the light dimmed this is legible to everybody -- that we extracted from those that you posed to us. They are listed here but before I tackle them, I should say something about the scope of what we have tried to do. As you said, Lord Burns, the two presentations you will hear this morning are both from scientists and we have tried to restrict ourselves to scientific enquiries, so clearly there are questions about hunting that are beyond our remit. Another difficulty that we face is that many of the things we are measuring and might like to compare are what we might call "incommensurable" in the sense that they are measured in such different units that deciding how one should be traded off against the other is extremely difficult. For example, we might find ourselves trading off metres of hedgerow preserved against units of suffering and there is no easy metric for that in science as yet, it is a problem that besets all of conservation and biology. There is one third caveat which is, in a sense, more prosaic but, nonetheless, impeding that is -- at least in our report -- we discovered that in many instances the data that are crucial to resolve any questions you formulated for us are simply not available, or only fragmentary available so we are not going to be able to provide many glib, short and simple summaries. Nonetheless, what I am going to do now is to try and work through the answers that we have formulated to the six questions that you see on the board, beginning with, "Why seek to control foxes?". Why do people seek to do so? But taking up this point I have made that there is often a shortage of information with which to answer these questions, I thought it would be helpful to begin rather than to end with a list of things in which we found data to be lacking, or open to widely different interpretations. For example, we find that estimates of damage caused by the species in question are often somewhat unsubstantiated. Data on basic population biology of the species concerned are often rudimentary, that makes predictions very difficult to make. We find that the relationship between different sorts of mortalities are generally completely unknown, so we would find it hard often to predict what the compensation for the change of one mortality might be amongst others. We find that actually, with the exception of hunting in its various forms, estimates of the culls made by different methods are largely speculative. When it comes to measuring humaneness, which was the topic of yesterday's seminar, our judgement is that this is a very, very important science but one that is in its infancy, also making interpretation far from easy. So why do these different interest groups -- we have listed five here -- seek to undertake control of the species groups that we have illustrated on this table, which is a brief summary of the main motivation? The first thing to make clear to you is, amongst the list of caveats, that each of these types of people, farm managers, foresters and so forth, are not necessarily exclusive; they are often the same person, different days of the week. Also I want to point out that this is about why people say they seek to control populations and the species and I point out to you that seeking is very different to achieving population control. It is also important that the actions and the decision to seek to control these species is based on people's perceptions, but later we will ask something about the quality of the evidence that leads them to have a perception that motivates them to seek to control these different species. It is important also to remember that the complexity in this is that each of the species concerned may have a multiple personality, if I can put it that way. I might, for example, see a red fox soon after sunrise trotting across the horizon and think of it as a splendid aesthetic element of our biodiversity. That same fox might be seen by a sheep farmer who believes it to be an agricultural pest, or a poultry farmer, or by a game manager. It might be seen by somebody who is interested in the fur trade. It might be seen by a sportsman who sees it as quarry. In some places a public health official might see that same individual as a vector of disease. On the list goes, so there is no one dimensionality to any of the measures and perceptions that we have here. By the way, this little table of the principal motives for people seeking control excludes sport as a motive, because we do not see sport as a motive for seeking control. We see that as a different motivational basis. Why then, for example, do farmers seek to control foxes? That has been the subject of many questionnaires of which we report on just one here. It compares the answers for three different areas: Wales, Midlands, East Anglia, and you will see that this produces a ranking of why farmers say they are concerned to control foxes in this instance. Now, there is a number of points to take from this picture, further adding to this tedious multidimensionality that the problem has. One is that most of those farmers had more than one motive, and the figures now shown at the bottom as percentages are those that say they have more than one reason for trying to kill foxes in the area. Another point is that there is regional variation which we see as rather important, so, for example, you see that preserving game stock is different, differently ranked in different places. Similarly, livestock differently ranked in different places and sport differently ranked in different places, so it is hard to come up with a uniform answer to even a rather simple question. Also, beneath these tables there is a difficult other tier of variation. For example, the foxes that were shot in this particular study, or rather the foxes killed in this particular study, were killed by different means. In Wales 73 per cent of those that were killed involved dogs in some way in their death, whereas in Norfolk 64 per cent involved a spot lamp and a rifle, so everything is essentially different. "Why do people seek to control deer?" Well, there have been ADAS surveys, of which a recent one in 1999 asked four different interest groups -- each of them displayed on this slide -- what percentage of the land or estate owners or managers in each of the categories, forestry, agriculture, conservation or recreation, believe they suffered significant damage from deer and you will see the percentages given here. Forestry is, without doubt, the arena within which deer damage is most widely perceived and most widely accepted. In the agricultural context there has been a series of surveys summarised in our report which tend to suggest that on a regional basis or widescale basis deer damage is not so significant. However, on a local basis, even one field or two fields within one farm, it may be so. "Why do people seek to control mink?" Well, it is mainly conservationists who seek to control mink, at least at the moment, and the reason why is illustrated by these two maps here which show a study -- in fact my own group was involved -- in the Thames catchment where we compare the distribution of mink, on the squiggly lines which are part of the Thames catchment river bed, and we compare the distribution of mink with water voles in 1975. You will see that over successive years the relative distribution of these two species has been reversed. There is now rather compelling data that one of the factors leading to the demise of the water vole is indeed the influence of this imported alien species, the American mink. Again, however, there are subtleties and many preconceptions and prejudices. For example, in the same area, we have looked at the relationship between the mink and various water birds, for example, the coot and the moorhen, which you might have thought are superficially similar, but it turns out that the impact of the mink on the coot is rather significant; on the moorhen not very significant because of differences in the life history of these two prey. Moving on to the next question which was, "How do people seek to control these different species?" You can see another horrible matrix. Life would be simple for your Committee if every aspect of control of any of these species fitted cleanly into one or other of these categories. However, the difficulty that we have faced is that many activities involved in attempted population control defy ready classification within this sort of matrix. For example, you might consider the operation of gun clubs in part of upland Wales where hounds, terriers, guns, and everything that can be mustered, in fact, is all brought together in an attempt to control foxes, so classifying some of these activities is a bit difficult. Nonetheless, obviously the legal options at the moment are shooting, hunting with dogs, trapping and snaring. There are regional differences regarding the use of dogs in the control of foxes and that is just summarised briefly here. Again, of the three areas I mentioned to you before, a study undertaken by Jonathan Reynolds, who is with me today from the Game Conservancy, which shows different categories of dogs, mounted hunts, by which we mean the traditional classic sort of hunting that most people have in mind when they talk of fox hunting: foot packs, gun packs, which are dogs used to bolt foxes on to guns, and going to ground with the terriers. You will see again that between the different regions the proportion of these activities varies widely and many of the farmers who reported these percentages of activities on their farms actually are involved with several of them. 92 per cent of Welsh farms involve some sort of use of dogs, for example in the control of foxes. Turning to stag hunting, this is the distribution of red deer in this country and the little red area in the south-west, which I hope is visible to you, is the area where hunting with hounds occurs. A recent survey, which involved Jochen Langbein, also with us here today, showed that 73 per cent of Quantocks farmers permit or encourage hunting with hounds, 31 per cent of them also use shooting to control their red deer. Well, the next question is, "What is effective in terms of control of these different species?". It is terribly important that we get this straight because there is a beguiling misconception lurking in much of what is written, and that is that simply killing a lot of something is somehow effective. Numbers killed, catch per unit effort you might say, is actually not a terribly good measure of whether something is effective because you have to take into account how many were there in the first place. That point is illustrated rather vividly by this comparison between the efforts of two gamekeepers on two comparable estates; one in south-east England and one in east England. What the top pair of graphs shows of these two blokes is that when they went out, about twice a week, spot lamping with a rifle to try and shoot foxes, the chap in the south-east was seeing about three foxes an hour, whereas the chap in Norfolk was seeing under half a fox an hour trundling around, there were fewer foxes there. They took pot shots at these foxes whenever they got the opportunity and, therefore, accumulated a cumulative tally throughout the seasons from August to March that you can see shown on the lower graph. The point of this parable, if you like, is to show that while the chap in the south-east was seeing more foxes and was shooting many more of them -- in fact he clocked up 60 -- he made no observable difference to the number of foxes he was seeing because other foxes were dispersing into the area from which he was shooting that abundant supply, whereas the fellow in the east of England shot only 20 foxes, but by doing so effectively wiped them out. When we come to talk about effectiveness, we must bear in mind it is quite a difficult thing to measure and involves careful consideration of efficiency, which is also different to measure. We have reviewed in our report, as some of you will have seen, as much as we could of the evidence on effectiveness. I realise it is a crucial question to your Committee and we come with the generalisation in terms of hunting with hounds and dogs, and that is that if reducing numbers with the intention of protecting a game or agricultural fisheries interest is the prominent aim of the whole exercise, then the various strands of the data that we have evaluated suggest that hunting with hounds is generally less effective than alternative methods that are available for all the species in question. Well, one of the things we have done is ask whether simulation models can help us. Let me explain to those of you who are unfamiliar with this sort of computer technique what its function is. Often in life there are inadequate opportunities, inadequate time and inadequate data to study complicated questions, and one way of tackling those questions is to set up a computer simulation. It mimics, in a virtual world, things that cannot currently be studied fully in the real world and there is some advantage to that because it is perhaps better to make mistakes in the virtual world rather than the real one. We have undertaken -- and the guys who did the work are here today -- three different modelling approaches, the details of which I am not going to go into very much other than to provide you with a flavour of the sort of results that they produced. The first of these is matrix population modelling. The idea there was simply to explore whether the differences in the life history of the different species with which we are concerned had some impact, as of course biologists know it would, on their response to given levels of culling. The output of these models summarised in this table here simply shows that the life histories of these species are so different that on a national level -- this is a widescale coarse grain modelling -- different levels of control are required, pointed at different age groups, to inflict some population control on the population. So, for example, proportionally much higher levels of control are required to induce control in hare and mink populations, according to this model, than would be the case in, say, deer populations and that is due to the reproductive biology of the species and in that sense, unsurprisingly, that reveals another layer of complexity that has to be taken into account. Individual based models are rather different. They involve setting up in the computer, with the aid of what is called a geographic information system, a real landscape within which animals are programmed to behave on the basis of what they are known to do in reality and from that behaviour a population develops that has certain characteristics. This allows us to model different control strategies in real landscapes. Now that revealed -- to cut a long story short -- for foxes that, as far as we could gather from the data we had available, mounted hunting with hounds in the traditional lowland sense has no effect on fox population radio control in these models. However, different strategies which we explored in this virtual reality, and remember these models are only as good as the assumptions that they make and the data with which they are fed, but we found that, for example, strategies that involved culling at the earth, culling vixens and cubs at the earth, and shooting did have the potential to control these populations. These sorts of models also allow one to uncover what is really important, or at least what may be really important in reality, and in this case with foxes the model suggests that a better understanding of dispersal is a process that is really vital to understand if one is to see how culling does impact on populations. Of course, dispersal is particularly difficult to study and particularly poorly understood, which is a pity. Similarly, the results for mink are along the same lines. The model suggested to us that hunting with hounds as currently practised, as we understand it, was not affecting the dynamics of the mink population. Trapping and hunting were capable of doing so within this model. How many red deer, and I would consider how many animals, are actually killed by each of the methods that we have exposed to you before? I am going to present the species in order, because the quality of the data varies as we go through them. So we have good data for hunting with hounds in terms of number of deer that are killed. You can see that one of the activities of the hounds is also to mop up additional casualties, which we spoke about in the seminar yesterday quite extensively, some 35 to 95 a year. There are estimates for the number of deer shot throughout the UK in this case, including the Red Deer Commission in Scotland, and 1,000 or so being shot in the counties where hunting takes place. Data for hares: a little bit less easy to deal with. The yellow bar here suggests data that seem to be reasonably firmly based, and those data come from beagle packs and regulated coursing, but we were able to find nothing to give us any clue about the numbers of hares that were killed by unregulated coursing and other activities. Mink: terrible paucity of data. You will see there is no yellow on here. Hunting with hounds somewhere between 400 and 1400. Trapping, we really have no idea, the more than 1,000 is just one survey which reveals that at least 1,000 are trapped, but that must just be a tiny drop in the ocean. Now foxes are a little bit different and I want to spend just a couple more minutes on the fox example. The yellow data shows that the better data has come from the surveys of mounted hunting, the records kept by fell packs, Welsh packs. There is some difficulty with the Welsh packs because the data, while good, have been under different collecting umbrellas as the structure of the hunting associations has changed, but we also have data for the number of terriers that are used outside hunts. It is hard to estimate, however, on the other hand, the number of foxes killed by trapping, snaring and shooting. This turns out to be fiendishly difficult and the figures that we have put down there are estimates based on a survey of gamekeepers who were asked how many foxes they killed and what proportion of the foxes they killed were killed by each method, snaring or trapping for example. So it turns out that gamekeepers say they trap -- live trap that is -- about one per cent of the foxes they kill. Surveys of how many foxes are killed by gamekeepers in total give estimates between 37,000 and 80,000, so one per cent of those would be between 350 and more than 800. So you will see the way these guesstimates were arrived at and you would be missing the point if you were to take these numbers too seriously, but I am just trying to show you the way we that try to stick together on these things. Similarly, with the shooting figure, that is quite an interesting one because what happened there was, first of all, there was a gamekeeper survey that said somewhere between 46 and 68 per cent of the foxes killed by gamekeepers are shot. So, again, using the total figure one can get a notion of how many they are shooting, but that must be a drop in the ocean in comparison to the numbers shot by non-gamekeepers. One way of looking at that, which we have done here, is to say from our surveys of farmers throughout the country, it has turned out that an average sort of figure for the number of foxes killed by farmers is about 2 per kilometre squared. We know that the sum of 340,000 square kilometres of England and Wales, of which about 70 per cent is farm land, and therefore in terms of orders of magnitude about 470,000 foxes might be shot, might be killed, I should say, on farms, but they are not all shot; some of them are killed by hounds, some of them by terriers and other things. If we deduct the figures we have for those sources of mortality we come out with this tentative thought that a bit over 400,000 foxes might be killed on farm land. We know that the estimate of foxes in England and Wales at the moment is about 200,000 or so. They will have about 400,000 cubs each year, which will have to die to keep the population stable, and so these estimates are broadly in the same sort of ballpark. But I make no more of it than that to show the way that we have tried to stick together figures in the absence of data. Moving on swiftly, this is a plot that simply shows that the more times hunts -- traditional mounted fox hunts meet, the greater the number of foxes they kill per kilometre squared. So kill is related to effort in a very linear near way for mounted fox hunts. We asked the question because I thought it was one you had posed in a sense by implication to us, about could they do more as well as less? So, for example, proportion of the foxes that hunts chase go to ground and a proportion of those are left. Could the hunt be more effective than it currently is? Well, if we multiply the mean number of foxes killed per kilometre squared by 2.5, that might take into account how many they could kill. The ones they leave have gone to ground and that would increase the effectiveness in the way that you have seen here. There is all sorts of possibilities there, most of them impractical for weather, equestrian and other reasons. An important regional variable to keep in mind is that there is a profound difference between the upland packs in Wales and the lowland mounted packs elsewhere in the UK, and you can see here the difference in the mean density of foxes killed per kilometre squared, as reported by those two different sorts of enterprise. Note that the Welsh packs are killing about ten times as many foxes, and they are killing them from an area where one might expect the population density to be lower, so the difference is more marked. We have tried, although I know you have economists on the team, to depart fairly gently into the water of the cost effectiveness of some of this, and I want just to make three brief points to you. We have looked at the cost of hunting in Wales and made estimates of the lamb losses that result to ask whether the cost of hunting is balanced by the loss of lambs that are incurred, and what might happen if we made simple projections as to the likely increase in fox numbers if hunting were banned. It is important to mention -- and vitally important to mention -- that all these estimates of losses are based on the farmers' perceptions, so the data are unverified as to the extent of fox predation in the first place. So this whole thing is based on, well, technically upon a castle built on sand. Also there is the assumption that there is a linear relationship between the number of foxes and the amount of damage they do, which is entirely unvalidated. These assumptions are crucial. Nonetheless, they show that in Wales, at the moment, and under those improbable assumptions, it could be profitable in terms of sheep farming to kill foxes in a way that they currently are. The answers are rather different for Midlands stock farms, but the point I wanted to make mainly here was concerning arable farms where the foxes are not causing any damage to the arable farmer in terms of its agricultural operation, but they are eating rabbits which cost him a lot of money. We have tried to calculate what they are worth and this is the graph here which shows that because the rabbits that are eaten by foxes breed, or would have bred had they not been eaten by foxes, the advantage of the fox eating those rabbits accumulates over successive years as the descendants of rabbits that have been eaten by foxes are not born as a consequence of that. "How effective are control methods?" -- I am going to wrap up very shortly, Chairman. As typically practised, the result of our review is that organised hunting by methods involving dogs for all these species, does not appear effective for any non-recreational aim in terms of population control, with the possible exception from the data we have seen of fox control in mid-Wales and sheep farming areas, and remembering the proviso that the data on lamb losses are largely unverified. Shooting, according to our evaluation, generally contributes most to effective population control. An exception is the trapping which appears to be the most effective way to deal with mink. If you need to answer questions about effectiveness, by the way, ultimately you need to do an experiment which is almost never done. An exception is the often reported Salisbury Plain experiment where the world was divided into a series of grids -- pictured here in different colours -- where two areas were over a series of years successively subjected to intensive predator control, or no predator control, and the consequences of those things are then measured. But this sort of experiment has rarely been done. "How acceptable are control methods" was largely the topic of your meeting yesterday, and so I do not propose to go into it, other than we have listed the topics which seem to be relevant. And also I just simply put here the graph which illustrates that farmers, at different times in history, have held contrasting opinions about the acceptability in terms of humaneness of different killing methods. This is one sample you can see that somewhere approaching 16 per cent of them felt hunting was humane. The answers are different from different surveys in different places. The final point is: "What are the wider impacts of hunting on the countryside?" Not strictly part of our brief, but something on which we have touched. These data here summarised for 1981 and 1998, the length of hedgerow, or the density of hedgerow, removed by farmers whose main recreational interest was hunting, shooting, or both, or neither. Interestingly, and I think relevant to your considerations, is that the answers in 1981 were different to the answers in 1998 because the world was a different place, especially for the farmer. So, in 1981 it was the case that hunting farmers had removed significantly less hedgerow in the previous decade than other classes of farmers. There is no such difference in 1998 where the world of farming and subsidy is unrecognisably changed. Although, in the 1998 sample there is a significant increase in the number of hunting farmers who say they have retained the hedges they have retained because of an interest in hunting as a motivating factor. So to conclude: what is the likely impact for a ban on hunting with dogs? Three questions appear to arise out of our consideration of the original six that you put to us. But before putting those questions to you, I must say again that much of what we have discussed and considered is evidence for the effectiveness of, or other things to do with population control. Population control, however, needs to have an aim and so we must be sure that if we are undertaking population control, that it is the appropriate action to deal with a particular problem, i.e. the problem indeed exists in the first place. We must remember when posing that question the answer may be very different regionally. But the three descending questions appear to be: can the contribution to the cull, currently made by hunting with dogs, be provided satisfactorily by other means? This is a numerical question when I say "satisfactorily". The answer for mink and for deer is straightforwardly "yes", as it probably is for hares. For foxes, the answer is probably "yes", for mounted packs, but less clear cut for the combination of terriers and gun packs that operate in upland Wales. The second question descending from that is: will a ban on hunting make landowners less willing to tolerate the quarry and hence, to then cause a decline in the species because of that loss of tolerance? We are unaware of any hard data on this sort of compensatory action, but there are plenty of bits of circumstantial evidence from questionnaires of what people say they would do, be it in the case of deer and hares and foxes -- there are no data for mink -- there is a suggestion on behalf of people, farmers in particular, that they would take action, tolerating less, animals that they have previously tolerated for being available for hunting. A paradox, of course, of hunting is that while on the one hand it may be interested in controlling species, on the other hand it may be interested in having an abundance of it to hunt. The final question is: would any such change that could result from question two be detrimental if, for example, people shot more foxes because they hunted fewer, would it be a bad thing? We can only speculate on the answer and point out to you that it is essential in all aspects of conservation biology and wildlife management to be clear about what you want. At the moment, people are not. So if people want more or less foxes, that will be important to knowing whether it is detrimental or not to have more or less, and how to arrive at those decisions is difficult. But a final point, that I imagine may be shared by all of the biologists on this table, is that whatever happens it is important to monitor carefully what goes on, and at the moment in this country, there is no adequate system for doing that and so whatever course of action is followed, it should be accompanied by a detailed monitoring system so that future generations of people do not have to struggle with such fragmentary data as we have all had to here. Thank you very much.
THE CHAIRMAN: Thank you very much.
PROFESSOR HARRIS: Thank you, Lord Burns. Well, I have decided I would be cautious and use overheads in case my computer crashed, so I hope they are legible. I am not sure, Lord Burns, whether you asked us both to do this contract because you had faith in neither of us, but I think you should be reassured to discover that we have actually come to very broadly exactly the same conclusions. So, from that point of view, it means that I think my talk will be curtailed a bit and I will therefore try and catch up the timetable for you. We did the same with a different team, looked at the same two contracts, and obviously exactly the same objectives, and those are the objectives we tackled. I am not going to go through them again, you know the objectives. Clearly, we have both had quite extensive data sets. I am not going to talk on all those objectives today. What we have tried to do is summarise a number of the key points we wanted to discuss today in the form of comparative tables, in the hope that these are easy for you to assimilate. They will be mainly in the form of ticks and crosses, rather than hard figures because we think that is easiest to assimilate in this sort of seminar. Our approach was much the same: we have done a literary review; we have done some computer modelling; we have actually done quite a lot of survey of organisations, practitioners and general public, during the course of this month. This was mainly by telephone and postal surveys. We have asked people about the perceived pest status of these animals. The effectiveness and acceptability of control methods; we have quantified data and control practices. We have asked people their opinions on what would be the future changes in control if hunting with dogs was banned, and what the crucial aspects of the data we collected was not just simply to ask them "yes" or "no", but to rank these data, so actually in the report you will see there is a more sophisticated analysis than what we are presenting here. Obviously, Lord Burns, you set us a timescale and we have worked to it. We sent out --
THE CHAIRMAN: Can I just say that somebody else set us a timetable.
PROFESSOR HARRIS: I understand that, Lord Burns. I should say the powers on high set you a tight timescale and you passed on the grievance to us. We have contacted 105 organisations. At the time, at the end, we only got a reply to 31, so we are not going to talk about the response in fact to organisations. We are going to talk about responses we have hard from practitioners and also the general public. We had 89 responses from the general public. From the practitioners, there is 198 at the time we did the analysis. By "practitioners", we mean farmers, foresters, fish farmers, gamekeepers, nature reserves, managers. We have defined a number of regions, seven in total, which we think reflected different patterns of hunting and different attitudes to the species in question. In the final report there will be slightly more data in there as well. So what I am going to do is run through the reasons people cite for control, the prevalence and the perceived effectiveness of control, the evidence for effectiveness of control, the acceptability of control, the hunting with dogs and, finally, the areas of agreement and disagreement, and some comment on future research. I will do that very tentatively, simply because scientists are famed for always saying we need more data. I do not think we do need more data; I think the evidence is fairly clear, but there are areas where, clearly, it would be nice to know more. So, okay, people cited reasons for culling, and you will see there are two columns for each reason: one is in black; one is in red. The black lines are from the literature; the red is from our questionnaire surveys. For foxes, people wanted to cull mainly for perceptions of predation on livestock, game, and so on. Also for conservation values; also to reduce abundance -- this widespread perception there are too many foxes. David said: "We would like to know how many foxes you want in Britain or how many foxes we should have in Britain". None of us know, but there is a perception that we have to cull them because there are too many. For deer the reasons are much more focused: mainly to conserve damage; also public health concerns, in some way for that cull to reduce numbers of road accidents and factors like that. For hares, it is mainly damage to forestry, agriculture, to reduce poaching. For mink, it is mainly predation conservation interests. What we have tried to do is look at the prevalence of methods of control and, again, this is just a brief summary, looking from very common through to moderately common, uncommon and restricted in use, and, again, comparing the information from the literature and the information provided from our polls of practitioners. As you can see, there are differences in approaches to different animals. For foxes it is mainly control in the forms of culling, or the other forms of controlling problems, things like habitat management and things like that require (inaudible) repellents, and so on. For deer, again, it is mainly culling, but there is quite a regular use of (inaudible) and tree guards as a form of controlling of damage; more so for hares and rarely for mink. It is mainly a culling practice. If you go on and actually look at the way people perceive the effectiveness of control, this is actually quite interesting. Again, there were regional differences in the way people perceived the effectiveness of control, but, again, looking at it: very effective, moderately effective or ineffective, shooting was deemed to be moderately to very effective, though quite a few practitioners actually expressed the view that night shooting was not particularly effective. Generally, if you look at hunting with packs; practitioners view hunting with packs as being effective, the same for foot packs, the same for digging out foxes, and so on. So we have some idea of the relative effectiveness of these different forms of control, as perceived by practitioners and I do say that is simply perception data. Now the big question we have to say is: okay, is culling effective? The problem is it is impossible for us to actually tell you whether culling is effective, because nowhere can we find anyone who gives us a very clear idea of what they are trying to achieve in a culling programme. There is no clear yardstick against which to measure the effectiveness of what they are doing. David has alluded to that; we have the same problem. So any idea of whether culling is effective, it is very hard to make a very sound or rational judgement on that issue. But, generally, people believe that culling foxes to reduce predation of livestock is not particularly effective. Predation of game, possibly; the problem is predation of game, many of the game species are also suffering from serious habitat degradation and, for instance, things like grey partridge, culling foxes does benefit grey partridge, but the fundamental problems facing grey partridge is a habitat one and clearly habitat was better. It is not clear whether the impact of foxes will be anything like it may be at the moment. So trying to unravel all these issues is very difficult, and also some of them are actually very muddled in people's minds. Particularly the idea of predation game and conservation, it is often argued, for instance, for foxes that culling is important to conserve hares. Well, actually to conserve hares in the densities we probably want them recorded by the diversity action plan, culling foxes probably is not necessary. If you want very large numbers of hares to shoot, then, okay, that is where fox predation appears to have an impact. So there is a perception muddle in there as well that makes it very hard to identify and separate out all these problems. I should also say, by the way, there is a lot of perception around that many of these species have been culled to prevent transmission of disease. It is very hard to actually know in many of them what disease people are concerned about, but it is regularly said they are being culled to reduce disease. We then went on to try and look at the wider acceptability of the different methods of control and here we compared information we had gathered from the practitioners and the general public for each of the species and each of the methods of control. The first thing that should be pointed out is that things are more acceptable to practitioners than they are to the general public in an overall pattern. For most of the general public the only method of culling that seems to be acceptable is shooting and it is actually quite interesting if you look, many forms of culling are actually even unacceptable to practitioners; snaring of foxes is unacceptable by the practitioners and the members of the public. Digging out of foxes is also unacceptable to the practitioners and the public, as is the use of lurchers. Hounds are unacceptable for deer as far as practitioners and public -- for hares, they are unacceptable to the public only marginally acceptable to hunt hares with hounds from practitioners, and so on. There is a general pattern there of the public being less tolerant than the practitioners. Surprisingly, the practitioners themselves are very unhappy about a variety of methods of culling currently used. Perhaps that is actually not too surprising. In the final report there will be details of how we compare with Europe and actually we compare rather badly with Europe. If you look at all the Member States of the EU Council for Europe we are actually the only country that has no closed season for hares. They usually have restricted hunting seasons across Europe, normally it is just October to the end of December and some countries also have strict bag limits as well. Even for foxes, all Member States of the EU Council for Europe, except Austria, Hungary, Ireland, the Netherlands, Slovenia, UK and parts of Belgium have a closed season for foxes. It is generally a closed season to protect vixens and dependent cubs, but for five countries it is actually a very limited hunting season and they are given the same status as other game animals and they have a short hunting season and that is all. That is actually quite interesting, because certainly in the rest of Europe they do have a disease perception for foxes. Rabies was, until recently, very widespread and yet still they give them these closed seasons. The other point in Europe is that stocks and free running snares are largely illegal in Europe. There are only five EU states that allow the use of snares and we are one of them. So clearly we do not perhaps compare very well. We tried to look again at the culling intensity for each species by region and method and the problem we hit with these data is that clearly there is very little information. What we have produced here are some figures for the various regions looking at the number of foxes killed per square kilometre per annum by different means and basically exactly the same as David concluded from a different approach, very low density of animals killed with hounds, most have been killed by shooting. We put "other" there because also within that it is hard for the numbers being killed by farmers to separate out shooting and snaring. The only exception perhaps is in Wales where there is quite a high density of animals killed with gun packs and, again, that is the same conclusion. The problem we have though is that I am very unhappy about figures on digging out simply because the number of terriers I believe that David used is grossly underestimated. There is a larger number of terriers out there used by perhaps a less controlled element of society and they are killing very large numbers of foxes each year and trying to get a handle on the number they are killing is actually proving very difficult. So I would view a lot of question marks under digging out and that is simply because it is very hard to actually try and work out exactly what is happening in our countryside at the moment. The other species became even more nebulous so I have not even bothered to put those figures up yet. We then did some modelling and, again, I am not going to bore you with the modelling or the details of it. We put in a lot of factors into this model, looking at time of culls, different patterns of mortality, different forms of cull, patterns of aid structure, patterns of immigration, which is dispersal but from the other end, and, exactly as David pointed out in his models from the different approach, the factors most affect the effectiveness of your culling operation is basically the level of immigration. Timing of culls are also important and methods of culling that way, but also time of culls with respect to non-anthropogenic mortality. The basic conclusion is that the hunting with hounds had very little effect on fox numbers and overall it is very hard to be quite sure what impact the current levels of culling are having on fox numbers overall. For the hare model we actually had some quite nice data from East Anglia where we got a lot of data on hare population dynamics and so what we did was model the impact of different levels of culling, the impact of closed season and the pattern of culling from both shooting and through the year hunting with lurchers and others to try and see the impact on hares. One of the things that is easily apparent in the way our hare population is at the moment is that the level of production, particularly level of survivorship, is critically down on what we believe it was in the recent past and this has a big impact on the effects of any form of culling and basically it does not appear that recruitment is large enough to support the level of culling that occurs in one large shooting. Shooting sessions were held in the autumn and also the low levels of culling coursing during the bulk of the year, that again causes hare populations to decline. Closed seasons themselves will not actually prevent a population decline unless culling levels are quite low even during the open season. So hare populations are very vulnerable, they are very vulnerable to immigration rates and also rates of level of survival and they do not seem at the moment to be able to buffer themselves from difficult patterns of culling, and perhaps it is not too surprising that hare numbers are continuing to decline. We have not produced a model for mink yet and I explain why from this. We have talked briefly about animals numbers in Britain; this is mainly in Britain. I have not split it down for England and Wales. We do not use the same estimate for the number of adult foxes in Britain. Two points I would make about that: the pre-breeding population is around 240 adults, there is about 400,000 cubs being born each year. They are estimates we produced a few years back -- obviously you have to lose 400,000 foxes a year if the population of Britain is going to stay stable. I think I would take difference with David in his estimates, particularly in the impact of shooting. It is very hard to know how many are being killed by different forms of culling, but in his total he did not include 100,000 odd animals run over on the open roads each year and clearly, when you look at these sort of figures, it is very hard then to try and work out exactly how many animals are being killed by each means, particularly when a lot of it has been done clandestinely, so at the moment we have not produced a final figure for you, Lord Burns, on the number of figures killed by each means, but my figures, I think, are going to differ from David's. The other thing I point out, is that of that total 14 per cent of them live in suburban areas and they are effectively outside your remit anyway because they are not really affected by those patterns of mortality. I know in recent evidence you were told the estimate of the number of foxes in urban areas is an underestimate, I will actually advise you the estimate for the number foxes in suburban areas is the best of the two. It is the number of foxes in rural areas we are much more foggy about and, therefore, I would say the estimate for urban populations is more precise of the two, it is about 14 per cent. At the moment hares, again, are still declining. We have just had a new population completed. Britain as a whole is about 750,000 now, 10 per cent down on the start of the century as part of the decade and, again, that is perhaps not too surprising given the problems they face. Perhaps the most interesting one is mink and this is why we did not try to model the mink population dynamics. Mink have actually undergone a major population crash in the last eight years. Eight years ago the estimate was 110,000 mink as a minimum estimate in Britain. Using exactly the same technique based on recent data that has just come in, the person who produced the first estimate has now said that mink have disappeared from 50 per cent of the sites he looked at eight years ago and the population is only one-third of what it was eight years ago. The estimate now for the Britain as a whole is about 39,000 adult mink and that is a staggering decline, because not only have you lost about 10,000 adults per annum from our mink population, eight years ago they were producing roughly 272,000 kids so you have lost that number of kids plus the adults each year and the productivity is now quite a lot lower. That is almost exclusively due to competition with otters. There is actually no evidence it is due to any form of hunting pressure, or culling pressure or anthropogenic factor. Why we have not tried to model it is because no one actually knows how this competition in effect works. You do not know how the otters are actually competing with the mink and how the mortality pressures are appearing on the mink. All we know is that the population has gone down dramatically. What we do not also know is whether actually the population will continue to decline or whether it will bounce back once they have stabilised and you get a balanced position where otters recolonised much of their former range. So we leave it that their numbers are down dramatically. Okay, we were asked to look at the estimated impact on a ban on hunting with dogs and basically I think we come to much the same conclusions as David in his team. In lowland areas we think there will be no impact on foxes. Only about 6 per cent of all the foxes killed are killed by packs of hounds and we do not think in the lowland areas, a ban will have any impact. Again, in the upland areas we come to the same imponderable. No one is quite sure what impact gun packs are having and so we say in upland areas, i.e. in this case Wales, it is possible that it will have an impact and it will possibly lead to an increase in fox numbers but, again, that is speculative. We do not actually know whether the fox numbers in upland Wales are significantly below the numbers the environment can carry anyway. It is speculative; it could do. For deer we do not see any reason to suspect the increase. In the small number of hunts operating you only account for 2 to 5 per cent of the population compared to 8 to 13 per cent by other means, and we think it is quite easy for any form of culling to compensate for that, as it is, already culling is involved in the population in check. For hares we see a possible population increase and we think that should be good news, simply because biodiversity action plans featured, the aim of which is to double the hare population by the end of this decade, and that at the moment they are still going down so an increase would be good news. That would be partly because a lot of landowners are killing hares to keep lurchers and poachers off their land. In the absence of use of lurchers, particularly that problem may go away. For mink we do not see any effect and we do not have a clear idea where the mink population is going to go in the next few years. So if you are looking at levels of damage, then we come to exactly the problem David has already pointed out to you. There is no relationship between the numbers of foxes, deer or hares as far as we can see and levels of damage. We cannot find any simple linear relationship. Damage levels can be very patchy. David has already told you this: sometimes it can be a particular field or two, or one farm or whatever. It is a very localised problem. It is not related to population density so even if population densities go up or down following a ban on hunting, no one can actually tell you whether that is going to have any significant impact on levels of damage. For foxes we said no obvious change in lowland areas simply because we do not believe that there will be any impact on fox numbers following a ban on hunting. So for deer, deer numbers are already increasing. It is very unclear to us at the moment whether levels of deer damage are going up significantly following that population increase. For hares, well in parts of East Anglia clearly they do cause economic damage but, again, it is hard to quantify; we cannot get a good figure on it. We are not quite sure why in some situations there is damage and why in others there is not. If you look at the attitudes of practitioners to the perceived changes in levels of control they would undertake following a ban on hunting, actually this is quite interesting, in that most of them will actually show no change in the levels of culling foxes, or no change in the levels of culling deer and no change in the levels of culling hares and surprisingly really only 50:50 for mink. If you look at the different types of pattern of culling that they would use they is certainly not going to be a mass rush to use more snares, or anything like that. But also, perhaps more dishearteningly, there is actually not much evidence people might even at the moment start to contemplate looking at means of controlling damage rather than numbers and actually take up methods of looking at habitat change, greater use of tree guards, things like that. Most people still say, "No, we are not looking to use alternatives to culling". Overall, there is no evidence from practitioners to actually convince us that there would actually be a significant change in the pattern of these populations of culls following a ban on hunting. Very quickly, we listed areas of agreement and disagreement for you which will end up in your final table, but generally we did not find that too difficult to achieve. The control of foxes is widespread, undertaken for a number of perceived reasons. It is widespread rather than focused on specific problems. It lacks clear objectives on methods for assessing success. There is large regional variation in prevalence and culling intensity of different methods and hunting with hounds has low culling in comparison with other means and there is large variance in acceptability of different forms of culling. The areas of disagreement I think between various interest groups -- first of all it is unclear whether fox control is either warranted for the reasons commonly cited, there is no evidence of population density in relation to the ecological or economic impacts, and the other issues relating to a ban on hunting I have already discussed. They seem to be the main areas of disagreement, but I think our data at least answered the last two questions for you. For deer, again, there is many areas of agreement. Most of the deer in Britain, and there is at least 1.25 million -- that is probably an underestimate -- are managed by means which do not involve dogs. Hunting with dogs is very confined to a particular region and it has not been effective in controlling deer numbers. We do not know whether it has been effective in limiting deer damage to any significant extent. The one point of course that we have to bear in mind is that in the future there may be greater access to the countryside. Many deer practitioners have expressed the concern that if people had more access to the countryside, culling deer with rifles with traditional means would no longer be a practical option for them because the countryside would be too disturbed. We would actually want to do more driven shooting where they use dogs under control; one or two dogs working for a man to slowly move deer out of cover to be shot, and that may be a practice that would increase in frequency in time to come. Again, for deer it is unclear what impact hunting has with hounds on the greater population in terms of damage caused by deer and it is unclear whether a ban on hunting with dogs would have any significant impact on landowner attitudes. We could not make up our mind whether the data really convinced us that landowners would change their use of deer in the South-west, and so we put that down to the area of disagreement. For hares, again there are large areas of agreement in much of what we see. Hare numbers have declined; there are species of conservation concern. For most of the country there is little evidence of economic damage. What there is, is largely confined to one place, like East Anglia. It is also clear the impact of hunting with lurchers is probably considerable, but we find it impossible to quantify the figures of numbers of hares killed by lurchers entirely speculative and it is almost certain the current levels of culling have a major population impact. Areas of disagreement is that the impact of hunting with hounds and beagles, we are not actually quite clear whether they have any significant impact on hare numbers overall. We are not sure we could find much evidence the role of hunting with dogs in conserving hares. There is also disagreement over the reason for hare population declines and also methods of trying to improve hare numbers. Just a footnote I should say also, all the modelling work we did was based on hare populations in the east of England where they are doing better than in the west of England and whether that data is typical we just do not know. Areas of agreement for mink, again, are fairly general. There is a lot -- including introduced species detrimental to livestock, game and wildlife. Hunting with dogs, there is no significant mode of controlling numbers or their ecological impact. There is no evidence that hunting with -- that the mink numbers can be eradicated by anthropogenic means except (inaudible). Also quite important, there is no evidence that mink numbers are actually related to their ecological impact, and I go back to the point that mink numbers have crashed by two-thirds in eight years. Their main impact, as David said, was on water vole numbers. During that same period water vole numbers have continued to crash at an accelerating rate, so whilst mink have gone down, there is no sign yet water vole numbers have benefited from it, and it brings us back to this very basic point: there is no simple correlation between population trends in a predator and population trends in their prey. There is a lot of conflicting factors in there that make interpretation extremely difficult. The other point generally agreed is that hunting mink with dogs is a summer activity and is probably detrimental to repairing habitats and also species of conservation concern. There is no real areas of disagreement with mink. As a final point, you asked us to suggest future research. Much again, as David has said -- send me the cheque later please -- population dynamics of managed species. It is very hard to give you clear ideas of what is going on, because we still know remarkably little, even about species like foxes. Going on to the presence of cost and control practices in Britain: what is the real cost effectiveness of these different control operations? The appropriate behaviour of foxes is rather actually poorly understood and also, again, the point that David made, good experimental manipulations, look at single species of carnivore so you actually see how individual species interact on their prey rather than predators in general. So that is my brief overview. I think I say, Lord Burns, there is a large area of agreement there. We might argue a bit over numbers of animals in different of things, but overall, I think the conclusion is very much in concordance. Thank you.
THE CHAIRMAN: Thank you very much to both teams. I would now like to give people the opportunity of raising points of fact or clarification. I would ask people if they would, please, not to comment on the substance of the presentations at this stage. I would like to save that until we have had a first round of questions about facts and clarification. Obviously we are very happy for each team to raise points about facts and clarification about the presentation and paper of the other team.
PROFESSOR HARRIS: You did not expect us to fight it out?
THE CHAIRMAN: No, it is not a question of fighting it out, but I think clarification. But maybe we will give the first opportunities for this to others.
MR SWANN: Thank you, Lord Burns. Two points of clarification, please, for Professor Macdonald. The first one is that you talked about lamb mortality data and you said you had used farmers' figures. I would like to know, if possible, just exactly what figure you worked with. The Sheep Veterinary Society and MAFF have used figures of total lamb mortality attributable to foxes between 2 and 5 per cent in the worst areas and farmers' figures have often been as high as 50 per cent, that is their perception. I wondered if you could clarify the exact figure you worked with. The second point of clarification is some years ago I had the misfortune to have to prepare the rabies contingencies for one of Britain's offshore islands. One thing we looked at was control sinks, and we worked out that in intensive killing in control sinks, because there are maintained kill rates there must be an imponderable figure of immigration. I wondered if you could tell us if you put a figure for immigration into your population modelling, please?
PROFESSOR MACDONALD: The first one concerns lamb losses and I hope I was careful to point out that most of the data on lamb losses, of which we are aware, are those reported by the farmers and, therefore, in some technical sense are circumstantial. In the written report you will find a review of all the evidence we could find on this and, as you rightly point out, the percentages of pre-weaning lamb losses vary between the surveys of different sorts, as does the evidence for them. For example, I myself was involved in a survey some years ago where we did ask sheep farmers for the evidence that they had invoked when concluding that a fox had killed a lamb and a proportion of them stated they had seen the kill; a different proportion -- and I cannot remember the figures now -- said they had found dead lambs, fox earthers; a different proportion said they had seen foxes in the vicinity of the lambs and so forth, so you will immediately see the quality of those lines of evidence differs radically. In the particular calculations that we made, that I presented in summary here, the data came from a study in mid-Wales, which Jonathan Reynolds may choose to help me over, but I will tell you, since he was involved in it, that the summary of the situation is that the farmers in that particular area recorded a 6 per cent lamb mortality pre-weaning of which their estimate was 0.6 per cent of pre-weaning mortality was due to foxes. That was the figure we used in the little linear calculation I made for you. May I just pause and ask Jonathan if I have remembered those figures correctly? I have, good. The source sink business. You are quite right, this touches on the issue which I think both Stephen and his team and ourselves have diagnosed as a crucial consideration in the population dynamics of foxes and that is the biological factors involved in dispersal. I think I said dispersal is frustratingly a rather poorly understood, poorly measured phenomenon in all of these species, foxes included. The reason, just for those of you who may wonder why it has not been studied, is that to understand how dispersal works you have to operate over a rather large spatial scale because the fox starts in the territory within which it was born, which may vary widely in size between different parts of the country, and then may travel a distance which might average anywhere between three or four kilometres to extensive movements of 20, 30, 40 kilometres. To understand what has gone on, you not only need to know the circumstances from which the fox departed but the circumstances into which it arrived, which is so far a task that has defeated almost everybody and, indeed, throughout the whole class of mammals has rarely been studied effectively. So your question was: have we taken that into account in our modelling, I believe? While I can call on the modellers to help me out, again I would say that the answer is: yes, we have explored, in each of the types of models, the consequences of there being a sink, or a reservoir from which animals could disperse into the controlled population and in each of the type of models, so far as I have understood them, dispersal emerges as crucially important. The category of model that most allowed us to explore the importance of this phenomenon were the individual based models, those which occur in a real world landscape set up in the computer and that within these exercises one can undertake what is called sensitivity analysis. The meaning is intuitively obvious I think. You change each of the variables, for example the number of cubs that are born, the death rate, dispersal rates and distances, and find which of these changes has the biggest effect on the outcome and that sensitivity analysis in the individually based models revealed dispersal was one of the variables that had the greatest outcome on the population dynamics of the species and, therefore, your proposal that sources and sinks were likely to be important, is I think correct. Stephen, did I get that correct?
PROFESSOR HARRIS: Absolutely.
MR SWANN: Thank you very much, Lord Burns. If I could just ask to clarify the figure on lamb mortality you worked on was about 10 per cent for fox mortality, if my figures are correct?
PROFESSOR MACDONALD: 0.6.
MR SWANN: 0.6 of 6 per cent?
PROFESSOR MACDONALD: No, 6 per cent was lamb mortality.
MR SWANN: 6 per cent was lamb mortality?
PROFESSOR MACDONALD: Pre-weaning, as reported by the farmers --
MR SWANN: The overall mortality of --
PROFESSOR MACDONALD: Yes, and 0.6 of overall pre-weaning mortality in that calculation.
MR SWANN: Was due to?
PROFESSOR MACDONALD: 0.6 of all lambs, 0.6 per cent of all lambs.
MR SWANN: Was down to fox?
PROFESSOR MACDONALD: Yes. Just under 1 in 100 lambs were said by the farmers to be killed pre-weaning by foxes on evidence that was not reported.
MR SWANN: I still was not clear how that last percentage --
PROFESSOR MACDONALD: I am sorry if I was --
MR SWANN: No that is okay. Could I just ask another quick one on the sensitivities: on the sensitivity analysis, did you use a median figure from the sensitivity analysis or did you weight it one way or the other?
PROFESSOR MACDONALD: I will pass that to Steven Rushton.
DR RUSHTON: A uniform distribution between 1 and 38 kilometres dispersal distance, which are the published ranges from David's own work, from 1984. It was a uniform distribution because we did not have any knowledge of the statistical distribution itself. One might expect some sort of normal distribution around a mean -- or a skewed one with a median, but we used uniform distributions, largely.
MR SWANN: Okay. Thank you.
MR HART: Three points of clarification for each of the contractors, if I may. These are really layman's questions. First of all to Professor Macdonald, you talked about effectiveness and efficiency of hunting methods and I wondered if there was any way you could just go into a little bit more detail at some stage on the targeted control that certain types of hunting are able to afford, i.e. the specific rogue fox scenario which has been referred to at various other stages in the evidence? The second question, both contractors referred to mounted hunting having no visible effect on fox population levels. I am quite interested to know if you mean both ways because there have obviously been comments made about population levels being maintained as a result of hunting, perhaps at a level which would be higher than normal and that has not really been addressed, as far as I am aware, in the comments you have made. Thirdly, a very simple question really, when you refer to "control", do you actually mean a reduction in the overall population or do you mean a reduction in predation or in perceptions of predation? There are similar questions, if I may, for Professor Harris. First of all, you referred quite strongly to certain, or practitioners of certain activities, namely terrier work and lurcher work, as being unacceptable to the practitioners themselves. I think I know what you mean, but I would quite like to know exactly how they find it unacceptable and the basis for your comment. I am not trying to challenge, I am just trying to get a better understanding of exactly what you meant by that. Secondly, you referred in some detail to hare populations and the effect of culling or otherwise. Obviously, evidence submitted by the coursing fraternity and, indeed, the hare hunting fraternity generally has actually focused not on hare control but on hare management and I wondered if in any of your calculations you have taken into account the conservation benefits and the conservation efforts made by those two sporting fraternities in reaching the conclusions you put to us just now. You have also quite strongly put there was likely to be no change in the attitudes to culling by a majority -- I think 58 per cent or something -- of farmers or landholders that you had questioned. What I want to know, if you can explain, is if predictions that you have made earlier in your report about population levels either going up or going down, how long that view of actually not changing the status quo is likely to last, i.e. if you were wrong in your earlier assertions and actually the population then does rise or fall suddenly, will that 58 per cent of people actually suddenly think: heck, we have this wrong, we have to change. I just wonder how much you might have taken that into account. Thank you.
PROFESSOR MACDONALD: I will see if I can get my three straight. The first one I think was about the distinction I would try to draw about effectiveness, of which efficiency is a component, and whether that related, or what I can say about how targeted control including the rogue fox phenomenon might work. Effectiveness just to recap is something we believe must be measured against a goal and is not simply a matter of how many of something one kills. Efficiency within effectiveness is a measure of the effort expended to kill foxes that you know are there, that was the point I tried to make, or anything else you might know, contrasting the chap in the south-east with the chap in the east with quite different numbers of foxes, so we are clear, I hope, on some yardstick of effectiveness is achieving a stated aim or goal. Now, is there effectiveness in hunting with any of the species concerned, considering rogue individuals? And while others around the table may know of data or remind me of data that I am unaware of, I do not know of any data which could be used to evaluate the claims, for example that on-call hunting during the lambing season is or is not particularly effective in catching rogue foxes. Indeed, and frustratingly, I am not sure that biologists have any very good evidence that rogue foxes are a real phenomenon. There is an intuition that there may well be so and there is evidence, and I think this is strong evidence, that in the case of lamb worrying that most foxes are not lamb killers at all, and that only very, very few foxes, I could not hazard a guess what proportion, are significant lamb killers and the evidence for that is entirely straightforward insofar as that if even one fox -- if every fox killed even just one lamb, then lamb losses attributed to foxes would be staggeringly larger than those that are currently attributed. So we can see that most foxes do not kill any lambs at all and I agree with you that a possible construction, well you may be suggesting a possible construction from that, is that there are rogue foxes who kill very many. Biologists to the best of my knowledge do not have data on that and to the best of my knowledge there are no scientific data on the efficacy of hunting dealing with that problem. Another topic which you may also have had in mind -- I do not want to put words in your mouth -- which we have not been able to deal with because there were no data with which we could, is that part of the rationale, as I understand it, in the context of population control and traditional mounted hunting, with its both cull hunting and main hunting periods, is not only concerned with attempted population control, but also with the spatial dispersion of the foxes that survive. The notion being, if I understand it correctly, that the dispersal of young foxes from their natal range from the territory in which they are born might be encouraged or accelerated by hunting activities. To the best of my knowledge, again, there are simply no data on which one could evaluate that proposal or go on from there to evaluate the likely consequences for whatever the yardstick of effectiveness might be, so that is the first one. The second question was about effectiveness where we had, both teams had tended to the conclusion that traditional mounted hunting as practised in the lowlands was unlikely to, in general, have an impact on fox population dynamics, unlikely to single-handedly be responsible for controlling fox populations, but you asked the question: is there a possibility that it is beneficial in terms of increasing fox numbers as an alternative scenario? Have I correctly recollected the question? We do not have any data on that, I believe, but it was in a topic on which we had implied judgements when we posed the second of at least our final questions, resonated in Stephen's questions as well, about whether people might take some sort of compensatory, even retaliatory action, you might say, against certain of these species of hunting was banned because of the hunting paradox, that one not only may have an aspiration to control but also to have sufficient therefore for recreation or sport. There are groups of people in previous questionnaires, some of whom say: if there were not hunting, yes, we farmers or we game sportsmen would shoot more foxes and therefore there might be less. That possibility was a possibility to which we alluded in the second of our summary points but we cannot say what would happen, Stephen may chip in, or he has his own three questions to worry about, because his results, if I remember, showed that some people were proposing that view and others were not. So I think the answer is it is a hypothesis that we do not know the answer. The third one was something about control but I cannot quite remember what.
MR HART: Basically it was whether your definition of control was about reducing the overall population number or whether it was a reduction actually in predation levels or, which I think is significant, perception of predation levels.
PROFESSOR MACDONALD: It is kind of you in a way to ask that question because it is at the very heart of what both of us and our teams have been trying to say. So much of the technical goings on that we have tried to summarise for you this morning is about whether we believe in terms of population control any of these methods of attempted control are effective. By population control we mean that natural populations have a level which is set in some sense by the carrying capacity of the environment that they occupy, we might often attribute that maximum ceiling on the population to food availability, but it might be something else, like water supply or disease or something else. Anyway there is a maximum. When we talk about population control we are talking about population control by people, that is that the activities of people reduce the population to a level below that maximum at which it would otherwise achieve. So if the yardstick of success here is to reduce a population then so be it, population control would be achieving that yardstick. However, we would say, I think all of us would say strongly, that you could not legitimately have that measure of success unless you had some reason for wanting to do it, so you have to have all the steps in the chain completed. There is perceived damage. That perception is verified. You then say what course of action would reduce that damage and you have to verify the course of action does in fact deliver the goal that you have set, and that is why I was at such pains, I hope, to say that you cannot talk of effectiveness unless you have aims and I think both of us have said the aims are sometimes a bit hazy in all of this. So no, for me the answer to your question is: if you ask is achieving population control a measure of effectiveness? I would say no, the measure of effectiveness is reducing whatever damage it is that you are seeking to reduce by undertaking population control, which opens up the issue of whether there are alternatives and it may well be that something, nothing at all to do with controlling numbers but with controlling behaviour, for example fencing or repellents would be an alternative. Did I get the three?
MR HART: I will read the transcript, but yes, I think so.
PROFESSOR HARRIS: I have made the sad mistake of not starting to write your questions down because I did not realise it was going to be quite so long, so I apologise. I hope I get them right, but stop me if I get them wrong. The first two seem to relate to the information we put forward on perception of practitioners and how we scored them. In the actual report you will see that practitioners were asked to score their perception of acceptability on a scale of 0 to 10. Basically we have given in the report mean scores and a standard deviation, I do not know whether that is going to be particularly helpful, but anyway you have these mean scores, and for the slide I simply tried to rank them as unacceptable, moderately acceptable or very acceptable. So, for instance if you asked as to the mean scores of, I think you asked about snares, the only score, the mean score of acceptability of 2.29 compared to 7.17 for shooting at night with rifles and 6.40 for shooting at day with rifles.
MR HART: I actually asked about terrier work and lurcher works specifically not snares.
PROFESSOR HARRIS: Okay, again, terrier work only scored 3.22, lurcher work scored 2.13 less than snares. That is what the figures were, so all we are doing is reporting what practitioners told us. The second question I understood it to relate to what would happen if a population of these animals changed and whether people's perception of their attitudes to culling would change? Simply we could not really ask that because there is no way we could really ask people what would be an acceptable number of foxes or deer or hares in Britain because really there is no yardstick for people to measure that. So really we only asked them for their perception at the current situation. Clearly over time things may change but there is just no way we could assess that. Could you remind me of the third question.
MR HART: I can, it was whether you had taken into account conservation measures of the hare hunting fraternity?
PROFESSOR HARRIS: No, again we found that very hard because it is very hard to actually put any quantification onto the conservation measures; simply in terms of how it would benefit hare numbers which is what we were looking at, simply all we did was look at the effects of culling pressure at different levels of culling on the population environments of the species. That really is the only question we are trying to answer because you could equally well apply some measure to all the other species where it was impossible to quantify in the modelling prey, in the modelling scenario, so all we are trying to do is actually model the impact of culling on numbers. Does that help you?
MR HART: It raises a number of important issues. Thank you.
DR LINDLEY: I do not know whether I should introduce myself, I am new to the circle here. My name is Dr Arthur Lindley. I am Director of Science at the RSPCA. There were two questions, if I may. One related to what Professor Harris called "non-anthropogenic mortality", it might have been perhaps better to call it perhaps "non-targeted mortality", since what he was really talking about was road traffic accidents which are certainly anthropogenic.
PROFESSOR HARRIS: I was not talking about road accidents I was talking about natural mortality.
DR LINDLEY: Sorry, I thought you did mention road casualties.
PROFESSOR HARRIS: I also said there are road factors as well, but actually non-anthropogenic, I just meant natural mortality.
DR LINDLEY: The question really was between the two, Professor Harris, again I hope I did not get you wrong you indicated that you believe that those non-anthropogenic causes of mortality were a significant part of the total mortality of the fox population in a year, and yet it seems from Dr McDonald's presentation, certainly in a table that you showed of numbers of animals killed, foxes killed, the total numbers of foxes killed in a year, by hunting, shooting, trapping and snaring actually seemed to exceed the annual production of cubs, without any non-anthropogenic mortality at all, and I wondered whether that was my misperception or whether there were some provisions in there?
PROFESSOR HARRIS: Perhaps this is one area we might usefully put our heads together to see if we can come up with some meaningful figures because it is exceedingly hard. Let David answer.
PROFESSOR MACDONALD: I remember clearly the slide to which you are referring. I hope I introduced it by saying that what I was trying to illustrate to you was the sort of logic we could pursue to try and get some guess at the numbers of foxes killed by different mortality factors in the absence of adequate data. The particular exercise you have in mind is one where we started, exactly as Stephen's team did, with an approximate estimate of the number of foxes that exist in England and Wales and pointed out that if they breed at a conventional rate, then a certain number, we both said about 400,000 I think, will have to die by the following year if the population is to stay approximately stable. We were considering then what evidence there was for the contribution to that mortality made by different sources of human intervention. I made the point that, perhaps surprisingly, there are really no data on which we can readily call, regarding shooting. So, I said let us try the back-of-an-envelope calculation whereby we say roughly how many foxes are killed on farm land. We happen to know approximately from questionnaire data that it turns out to be 2 per square kilometre as a rough figure from the 800 or so farmers we asked in different regions of Britain. I said, let us imagine how much farm land there is, let us imagine from that how many foxes are killed on farm land and deduct from that figure the numbers known to be killed by other sources like hounds. That led me to the figure of about 400,000 again; foxes being killed on farm land. Stephen made the absolutely correct point that we already know there are other things killing foxes, like motor cars, and in fact, happily, there will be no difference between us on that. I was simply following through a particular progression saying if this, then that, if that, then the next thing. So all I am saying at the moment is, firstly and most importantly, I believe there is nobody who can tell us how many foxes are shot in Britain or in England and Wales at the moment, and that seems to be an important and regrettable omission. There are various ways of trying to deduce how many are shot and one really back-of-the-envelope progression leads us to believe that the answer is several hundred thousand. It may be less. We know that it is more than quite a few tens because there are fragmentary data, for example of surveys of gamekeepers, of which we know how many there are and how many foxes they shoot, largely. So we know that the number is going to be, say, more than 50,000 and less than the number of foxes there are. The figure I gave has no more status than that.
DR LINDLEY: Could I then just finally clarify. In terms of developing models, was there a provision for non-anthropogenic, if we can call it that, mortality, and how did you arrive at that as an estimate?
PROFESSOR MACDONALD: I will quickly answer and then pass to Steve Rushton to give you a more technical answer. The answer is yes, one of the beauties of functioning in a model is that you can alter anything you like, even in the absence of any data. Its capacity, we had in the model, to ask what would happen if levels of mortality were such and such, and so we could cover these options and, Steve, I think you could elaborate.
DR RUSHTON: We managed to get one estimate of non-anthropogenic mortality, and that was from the Game Conservancy and it was 14 per cent, which really Jonathan Reynolds could elaborate on. Essentially, what we did was to estimate confidence limits around that value, assuming it was a proportion which meant that we could simulate our non-anthropogenic mortality as lying between 5 and 32 per cent. In other words the confidence limits on that 14 per cent are 5 and 32, which is quite a high range in mortality. I would also stress that the other mortality factors were additive in the sense that they were treated as independent although they are probably not. Again, as I stressed in the report, there is little if any information on mortality itself. Although we know how many were killed approximately but we do not know the population size from which they were killed. Is that clear?
DR LINDLEY: Yes, I think that is clear so far, we may need to discuss this further.
PROFESSOR HARRIS: Do you want me to answer that point as well because you address some of the question to me? What I meant by non-anthropogenic mortality? I think there probably is a very high level of natural mortality out there -- the data we collected in Bristol. You could be looking at 25 per cent per annum of mortalities from a variety of natural causes and misadventures, which I am sure are likely to be replicated in the countryside as well. I guess we probably underestimate the level of natural mortality largely because we cannot monitor it and I would put it nearer 25 per cent. That is a back-of-an-envelope calculation but there is certainly a lot of natural mortality out there through a variety of causes.
PROFESSOR MACDONALD: Just to round off that same point or a related one, we all have several times and in the written report many more times, put in the caveat that we have made explorations based on the data that were available. Many of those data come from people's perceptions. When I was making that back-of-the-envelope remark that farmers recorded approximately, as an average, 2 foxes per square kilometre are killed on their land, I should point out to you that the quality of that data is open to question. For example, we did recently an intensive survey of the farmers' opinions in Wiltshire and asked the farmers the same question: how many foxes are killed on your land. They came up with an answer. We asked how many foxes were killed by hounds, by the hunt on your land and we asked the Master of Foxhounds the same question. The farmers believed that five times the number of foxes were killed by the hounds than the Master of Foxhounds did. So there are always reasons to question the data which I think in the written report, where we have more time to elaborate, we have been rather careful to put in the caveats.
DR REYNOLDS: I would just like to make the point that in doing ecology and studying these kind of systems, there is a general trade-off between being accurate and being general. So if you are looking for general answers that apply to the whole of the UK, you will not get accurate answers. As the members of our team will have learned by now, I have a personal dislike of what I call telephone numbers, which are so very speculative. I do not believe they teach you very much at all, although it is a great temptation to have such data about how many foxes are killed in Britain and how many die under the wheels of cars and so on. But I much prefer to stress the benefits of doing specific field studies which are targeted at a particular problem, or a particular region and come up with more accurate, not necessarily precise, but more accurate data. So that was the general point. If I may just respond to an earlier question as well, about the evidence of a positive influence of hunting on fox numbers. It is impossible to keep all the elements of this argument in one's head, and I am afraid David has omitted one. We did find evidence in the Game Conservancy's Three Regions Study, which you will have read about, in the sense that the hunt in the East Midlands had a restraining influence on gamekeepers and others on local shoots, to the extent that the number of foxes killed by those local interests on their estates was about the same as the number killed in mid-Wales or in West Norfolk. This was despite the fact that the population of foxes in the East Midlands was about twice what you find in mid-Wales, and about four times what you find in Norfolk. So there is evidence there that the hunt actually has an influence on other landowners.
THE CHAIRMAN: Could I ask a general question about population modelling? Just so that I can be clear. Given the shortage of data, presumably it is very difficult to actually verify the models and it is not possible to build a model which then simulates the behaviour of some area where the data is known. Or is it possible to build a model which will simulate what happens in particular areas?
DR RUSHTON: In theory one should and in fact in most of the published work that I have been associated with, one takes a separate set of data to validate your model and show that your model actually does simulate reality. In this particular instance we do not have sufficiently good data, either in the sense of populations against which to compare what is going on or the mortality data to go into the models in the first place. This is why we used the particular strategy for sensitivity analysis that we did. We took upper and lower bounds on each of our input parameters which we knew were logical. We knew for instance that the dispersal distance was somewhere between 1 and 38 kilometres for foxes moving around. Similarly the confidence limits that I suggested on the anthropogenic mortality were abstracted in a similar sort of way, given an upper and lower bound. If you can imagine all the different parameters that you are modelling, between a minimum and maximum, you do know that you are overestimating what is actually going on in the population, in terms of those underlying parameters but you do know that reality is somewhere in there. What we really ought to be doing is to try and focus down on the true nature of those distributions, so that we can get closer and closer and our universe of nonsense narrows to a focus point of reality. That is what all modelling is about. Although I should also add here, we did use these models didactically, in that we were trying to investigate how the system functioned in relation to variations in these parameters. I think the dispersal issue have both studies have highlighted is a key one here.
DR WISE: Lord Burns, could I follow up on this modelling because I have never been very mathematically astute but it occurred to me, I believe that Professor Harris suggested that hare numbers were very sensitive in his model to low levels of culling and that appeared to be different from the McDonald model. I might have missed the point, but could the contractors clarify whether they are in dispute over this or not.
PROFESSOR HARRIS: Are we in dispute, David?
PROFESSOR MACDONALD: I do not think so. Well, okay, Mark, would you like to say something here? We have, as you recall, three different modelling approaches and Stephen and Kieron have others. It is the case with models as with all other tools, which is simply what they are, that you can use different tools to explore different issues. I suspect that if there is any incongruity between what we said, it is to do with using different tools, with different assumptions, to explore the same question. The model that we were talking about which mentioned hares, Dr Shirley constructed and so you might like to say a word.
DR SHIRLEY: David has just covered basically what I was going to say. The two models differ quite dramatically, mainly because of their intent, the data that we were trying to produce out of them and the purpose behind the modelling. We were looking at a very general model, which would look at populations as a whole across a wide area, perhaps on a regional scale, whereas the models in the other contract were very specific to a particular location and that is something that Professor Harris said in his talk. This is one of the main reasons why there is such a big difference. There are faults in both approaches but, as we have tried to stress, we are trying to look at the sensitivity; we are only looking at the responses of what could happen when applying a cull. Particularly in the hare, because the populations can in theory grow so very quickly, it is quite hard, with the generic modelling approach that we use, to distinguish what is actually going on and to approximate the actual processes there. Perhaps Jonathan has got something more to say.
DR REYNOLDS: I just wanted to say that the essential difference, I think, between the two models is the amount of productivity that is built into the models. So, whereas Mark's model was based on quite optimistic productivity data from the Handbook of British Mammals, Stephen's model was built on rather gloomy data about the productivity of hares culled from a population in Norfolk. We have been discussing within our group about the hare model and I have to say we are a little bit puzzled at the moment because we have not seen all the details of how the model was constructed. So I would like to ask, if I may, just how the productivity data and the survival data for leverets that went into that model were derived?
PROFESSOR HARRIS: I think that is the crux of the problem. The data on hare productivity in the Handbook of British Mammals is very old. It is 1974, I believe. There is the Lincoln data and the data from about that period. I think that is the data you used, is it?
DR REYNOLDS: Yes.
PROFESSOR HARRIS: Since then there has been dramatic changes in the British landscape. One of the big problems has been this change, particularly in East Anglia, from the use of spring slide and seals to winter slide and seals. That had a big impact on the productivity and survivorship of hares throughout the summer and our data collected in recent years from a number of estates, spread not just in Norfolk, but Suffolk around East Anglia, all show exactly the same: because of the changing farming practice, leverets survive and productivity is actually much lower in the summer now. So we use those data in the modelling. I did stress that we do not know whether there is something similar going on in the west of England, where clearly there is not so much cereal crop, we just do not know. It is the only good data we have in recent years, and those are the data we used.
DR REYNOLDS: The thing that is really puzzling, if I may, is that the estates in Norfolk particularly, and also in the north of Suffolk that we know about, have the highest hare densities of any in Britain that we know of, and appear to be doing extremely well. These are particularly the estates on which they do hold shoots in order to decrease hare numbers. So it seems odd to have such poor productivity on the estates where hare populations are doing so very well; the field data and the model do not seem to match up. I would suggest that what is happening here is that we are looking at a very high density population in which density dependent effects are already taking place, and that the productivity of these animals is low in the summer because the populations are so high. I think that may well be a key difference between the models here.
PROFESSOR HARRIS: I think, Lord Burns, perhaps we are going down the line of speculation; I think that is completely wrong. I am not sure it is relevant, but I will answer it. The point is that many of these estates in Norfolk and Suffolk do not have high densities any more, and not all of them that we have hares from actually cull hares each year. Three of the ones we sampled also admitted that they can cull hares on their land in February as they do, and within two or three months they have got hares back and solely by immigration. Their populations have been maintained by immigration, not by productivity. Again, the density dependent factor is not in there because densities of hares on those estates are a lot lower than they used to be in the recent past. What is happening is that productivity is very low for a specific period of the year, and then productivity goes up again towards the end of the year before numbers have been culled, so it is not a density dependent effect in there; it is a habitat effect. We have got the data, and we have proved that. I think the data we have used are as realistic as we can, and they are a reasonable data set to use, and we have compared them with the data for the 1970s and we have actually gone back to the original source for those data, Dr Lincoln's data, and got his own data and compared them because they are from the same estates in many cases. The situation today is very different, and that is why we think it is valid to use those data.
THE CHAIRMAN: Could I suggest that, on this point, we do not seek to take it any further at this stage. I think we have raised an issue where there are differences. I think it is something that we would hope that the two teams might be able to sort out between themselves a little more, as we move to the next stage. I would like -- if there are no more points of what I would call fact and clarification --
MR HOBSON: Thank you, Lord Burns. Could I pick up on a point made by Professor Harris. In his presentation he said, I quote: "Hare numbers are continuing to decline". However, in a recent report published earlier this year called The National Hare Survey, by Bristol University, written under Professor Harris' name, he said, I quote: "There is no evidence to suggest that there has been a significant change in hare numbers nationally since the first survey in 1991 to 1993." There seems to be some divergence in the figures.
PROFESSOR HARRIS: Actually, there is not a divergence, I think you are quoting out of context. They have produced a number of figures in that report. It is not a published report, it is actually a newsletter sent for the volunteers who helped and it is the draft analysis. You say that the statistics nationally in Britain, in the few years and the decade, there has been a 10 per cent decline in hare numbers. What it then goes on to say is that that decline is not significant nationally, because actually the declines in some areas have been counteracted by, in some areas, small increases; particularly upland areas where hares are becoming more abundant in some upland areas. What it then goes on to say is that if you break the country down into regions, in many of the regions decline is statistically significant, and particularly in many of the arable areas of Britain and southern Scotland. So I think it is quoting a phrase out of context.
MR SWIFT: I too was going to raise a point about hare numbers, but I shall leave it to the two contractors to sort that out between themselves, if I may. There are, however, large chunks of Stephen Harris' report which are not there. That creates problems for us in making rational judgements about some of the opinions that he is expressing about hares and about other animals. The point I would like to clarify is on the practitioner and general public survey, the responses were given, but some of the sampled numbers were extremely small; I am talking about seven gamekeepers -- and probably analysed as being representative, I do not know -- and 83 members of the general public, and is that satisfactory, and how far can you take those sample sizes?
PROFESSOR HARRIS: No, it is not satisfactory. If you go back to the point that we did have a timescale, more responses are coming and in the final report we will have more information and, of course, to actually get contact with gamekeepers in the specific regions was proving problematic. That is why we gave your organisation a large numbers of forms and asked them to circulate to gamekeepers in that area. So we hope that we will get those back promptly, and we can add those to the sample sizes. All we can do is get people to see if they can fill the forms in and get them back to us.
MR SWIFT: Will we, through you, have an opportunity to comment on that before it goes into the final report?
DR WHITE: Can I make a comment in response to that question in the small sample sizes? Although the questionnaires we were asking are actually quite detailed; in the report it says that each questionnaire of practitioners actually took 20 minutes to complete, so we actually got 198 practitioners in total, which means a lot of hours spent on the phone. Because they were a lot more detailed than previous questionnaires, one of the comments about accuracy that you made, it is useful to compare them with previously published studies, such as the one that David did earlier. When you look at the general attitudes of practitioners such as farmers, then when there are questions in common, the results from our surveys do actually seem to bear out the results from his, which gives us some confidence in their credibility. On the point of the small sample sizes for gamekeepers in particular; because we had small sample sizes only for gamekeepers and most of the practitioners were farmers, that is why in the analysis we have decided to pool the practitioners as one lump of practitioners, rather than to subdivide them. We were also trying to concentrate on subdividing by region as well, so that is where the emphasis of the research was.
PROFESSOR MACDONALD: Regarding these questionnaire data, I think in our report we have deployed quite a lot of accumulated questionnaire data of one sort or another, much of it concerned with the opinions of people whose opinions are to be valued; people who are farmers or gamekeepers or whatever, who have first hand experience of many of the issues we are talking about. So I do not for a moment want to give the impression of being dismissive of those opinions but, irrespective of the sample sizes that lie behind them, I think there is a more important general point that we must be terribly careful not to lose sight of; that is, as both Stephen and I have mentioned in our presentations, have to be terribly cautious about what are perceptions, rather than demonstrable facts. I, for example, have participated in questionnaires where I have asked people opinion and I think they have answered me, so far as I know, honestly and on the basis of sound experience. But life is often not intuitive and things are often not as they appear to be. That is especially true in biological systems which are complicated, so when we sit here saying 73 per cent of farmers think this and 45 per cent of urban people think that, that is precisely what it says; nothing more and nothing less and please can we bear that in mind.
MR OLIVER-BELLASIS: Lord Burns, Hugh Oliver-Bellasis, representing the National Farmers' Union. Could I address a question to both contractors and then a question to Professor Harris. To both of the contractors: when talking about livestock, you have focused quite specifically on lambs, and I wonder whether you took into account piglets. The question specifically to Professor Harris: have you taken into account the changes over the last maybe four or five years to more extensive systems? You make a comment that in some of the cases of damage done by predators, that it could be avoided by better husbandry, and in one case you specifically mention housing and fencing. The extensive systems and the move to extensive systems with, particularly, pigs and poultry, puts a particular pressure onto that method of husbandry, both in terms of cost and other matters. I would be interested to know if, in fact, that was part of your calculations.
PROFESSOR HARRIS: Perhaps to address the question specifically to me first. Yes, clearly, it is an interesting question. Will the drive for more extensive systems in farming lead to greater problems? We did a survey, I think, three years ago of free range pig farmers, free range poultry farmers, and so on. At that time they all reported that basically their economic losses to foxes were actually very small, and most of them solved it simply by good husbandry, good fencing, and so on. So we conclude, at that stage, there was no real evidence to believe that more extensive systems would lead to greater problems. It may be that there will be greater costs and so on in the extensive systems, but not actually greater problems in terms of losses of foxes.
PROFESSOR MACDONALD: On the general one, you are absolutely right, of course, that at least I spoke in the agricultural context this morning mainly about lambs, that is purely an after-effect of how much time was available. But it is also the case, as you will see reflected to you in our report, that most of the evidence that we could gather, dismal though they are in quality, concerns lambs and lambing and we were unable to dig up very much on pig farming, although we would welcome, if somebody could offer them. I am fully aware, mind you, that in farming circles fox predation, at least on a localised basis on farrowing sows in the open, is widely talked about as being locally financially punishing to given pig farmers. I am unaware that -- though fully prepared to stand corrected -- of any data we could draw on there... But we do have at least a sentence in the report to reassure you, saying that pigs are an issue on which we think more data are needed, and the other thing that I did not talk about this morning is poultry, free-range poultry and again, other than noting that, for people that have free-range poultry on a small basis, foxes are undeniably and always have been a considerable nuisance and could become so, if market forces required there to be more free-range poultry; other than noting that, I was not aware of anything very useful we could say but I fully take your point.
DR VICTORIA EDWARDS: I have a very quick one on the mink population. Professor Harris, you said that there is evidence that the mink population is declining and I took that to mean the entire population nationally, and I believe -- I am sorry if I got it wrong -- I believe you said therefore we cannot deduce that there is a threat on the water vole population and yet I thought the study of the indirect relationship between the mink and the water vole was actually a site-specific study and it strikes me that it has got us back to Dr Reynolds' comment about looking at specific field studies and trying to draw conclusions nationally from that. Can you clarify? If we are looking at a national population in one case and a specific field study in the other we cannot actually draw conclusions, can we?
PROFESSOR HARRIS: I obviously did not make the point very clearly that the decline in mink numbers is national, and on the notepad I just gave the national figure. In the report -- in the final report -- you will actually get a regional breakdown of that, so that in a regional pattern, declines are greatest in areas where there has been dramatic otter population recovery. In some regions the mink decline has been as high as 80 per cent but nationally the average is something like two thirds. What I actually said was that nationally the mink population has gone down substantially and at the same time nationally because there are two parallel surveys there. The water vole populations also continue to go down substantially and, in fact, the data on mink and water voles are actually collected at one and the same time, so I think they are directly comparable. David referred to a specific study he had done. No one denies that mink are having a dramatic impact on water vole populations. The only point I made was that here was one example where we could clearly see that there was not a simple relationship between the number of predators and the impact on their prey. I made no other deduction other than that.
DR LINDLEY: Could I just come in on that, it is really a question to David. Am I right, because David has done all the work, that there is evidence in that localised study that the impact that mink were having on the water vole was an integral part of the impact of constrained habitat, particularly with the narrow corridors of modern waterways and that there was some suggestion that the effect the mink were having was only in the context of depleted and reduced habitat quality.
PROFESSOR MACDONALD: I have been involved with the work, but only in the sense as part of a team of a lot of other people. As Stephen says, there is no conflict between the two sets of results on which we chose to draw. There are two phenomena taking place which are simultaneously true and can be integrated. On the one hand, there really is very abundant evidence -- I think more than this committee wants to hear right now -- that, locally, the arrival of American mink had introduced alien species into river systems from which they were formerly absent and where water voles are present, leads to a rapid and dramatic decline and often local extinction of water voles and I do not think there is anybody that would dissent from that view. The mechanism that is involved is one that is rather interesting because, while there are some places -- many places -- where the arrival of mink is detrimental, indeed terminal to water voles, there are some places where you get those species together and there has been a line of inquiry which I have been interested in which asks whether loss of habitat, in fact what were once swathes of riparian habitat, now narrowed through riparian engineering and intensification of agriculture to a single ribbon, causes such a thin fragmented sliver of habitat that, even if mink were not there, water voles might be in serious difficulty. And Stephen also, I think, mentioned habitat restoration as one of the possible tools open to us now to solve wildlife management problems and it is exactly in that context that he might well have been thinking of habitat restoration. There is some debate about the extent to which, if we control mink now, water voles might recover because of the habitat uncertainties. There is no debate about the fact that mink are detrimental to water voles, almost irrespective of habitat. There is no debate about the fact that mink numbers, very interestingly, are declining, as Stephen says, on a national basis, partly, possibly explicable, as he says, by specifically competition with otters, so these things are actually all simultaneously true and leave us with some interesting practical and moral dilemmas. On the one hand, the practical dilemma is how to restore habitat whatever; on the other hand, one might ask, if mink numbers are going down, will that be sufficient for water voles to recover. Maybe the answer is no, because maybe the habitat is so shot to pieces and the water voles now so rare anyway, that the natural recovery in some areas is already a lost cause. The moral aspect of this, by the way, perhaps not today's conversation but for another day in your seminars comes about in the attitudes people take from a welfare point of view towards the control of introduced species as distinct to species which are native.
THE CHAIRMAN: I think that takes us probably as far as we should sensibly go this morning. We should break now for an hour for lunch. What I propose to do when we come back is to go through the subject species by species and basically look at three headings: one is what is happening to population levels; the second is the reasons for population management; the third is the effectiveness of different methods. I will invite other members of the seminar to comment on each of those areas in relation to the reports and then get your responses. It is going to have to be a bit of a quick chase through them in the time that we have. But if people could, over lunch, try to concentrate their questions under those headings, if possible. By that I do not just mean questions, I mean alternative views. If people wish to put them forward and challenge the views that have been set out in the reports we will give you all an opportunity to respond. So we are missing out, in a sense, the stage of general response to what we have seen. I think, given the amount of time that we have taken, we need to now focus in under the headings that I have mentioned when we come back after lunch. Thank you all very much.
(Adjourned for lunch)
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