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Wildlife and Countryside

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Non-native species

Invasive non-native plant and animal species are the single greatest threat to biodiversity worldwide with the exception of habitat destruction and are the greatest threat on islands.

Public consultation on:
the Review of Schedule 9 to the Wildlife and Countryside Act 1981 and
the Ban on Sale of Certain Non-native species

Defra and the Welsh Assembly are seeking your comments on proposals to review schedule 9 to the Wildlife and Countryside Act 1981, and to ban the sale of certain non-native species, in England in Wales.  The Scottish Executive carried out a separate consultation exercise for Scotland between November 2006 and February 2007.

The consultation contains proposals for updating the list of non-native animals and plants under schedule 9 of the Wildlife and Countryside Act 1981.  Most of these species are already established in the wild, but further releases are allowed only under licence.  The Joint Nature Conservation Committee (JNCC) has recommended species for addition or removal from Schedule 9, which we are now consulting on.

The consultation also looks at banning the sale of certain invasive non-native species under section 14ZA of the Act.  These species are considered to be strongly invasive and there is a real risk of escape and spread into the wild as a result of their presence and availability through trade.  Natural England and the Countryside Council for Wales have recommended species for inclusion in a ban on sale Order.  Key stakeholders have been pre-consulted on this list.

There is a provision in the Wildlife and Countryside Act 1981 to licence exceptions to the prohibited acts, subject to any conditions the licensing authority may consider appropriate.  Such licenses may be general or specific and may be granted to persons of a class or to a particular person.  The licensing authorities are Natural England and the Welsh Assembly Government.

You can access the consultation document, Impact Assessments and consultation response form at www.defra.gov.uk/corporate/consult/wca-schedule9/index.htm and associated news release

The consultation runs from 8 November 2007 to 31 January 2008.

Latest news

Introduction

Invasive non-native animals and plants have serious negative impacts on native species by predation, competition and/or spread of disease. They transform habitats and can threaten whole ecosystems causing serious problems to the environment and to the economy.

The vast majority of non-native species introduced to Great Britain over the millennia have caused no significant harm. In fact, many contribute to economic and social well-being through their use in certain sectors such as agriculture, forestry, horticulture and the pet sector.

But, given suitable conditions, some non-native species find themselves un-checked and able to dominate native species, transform ecosystems or cause general environmental harm. These are invasive species.

Invasive non-native species threaten native species and their habitats, and are capable of causing damage to economic interests such as forestry, agriculture and fisheries, probably of the order of several billion pounds annually in Britain . For example, it is expected to cost many millions of pounds to deal with invasive weeds such as Japanese knotweed the sites of infrastructure for the 2012 London Olympics.

The true extent of the threat posed by non-native species has become much better understood in recent times and past introductions have usually occurred with little knowledge of the potential consequences. The Millennium Ecosystem Assessment report "Ecosystem and Human Well-being: Biodiversity Synthesis" notes that control or eradication of an invasive species once it is established is often extremely difficult and costly, while prevention and early intervention have been shown to be more successful and cost-effective. Changing conditions, such as climate change and greater global movement of people and goods may make it easier for non-native species to become established.

"The most important direct drivers of biodiversity loss and ecosystem service changes are habitat change ., climate change, invasive alien species, overexploitation, and pollution." Millennium Ecosystem Assessment report.

Climate change will have a substantial impact on species assemblages in the coming years - both by affecting the distribution of our native species, and by enabling some non-native species to become more common. Increasingly we could see more non-native species that are currently benign become invasive as the climate changes. Already we are seeing some evidence of animals occurring outside their usual or expected ranges. Recent research also shows that the (generally northerly) expanding range and abundance of some mobile species including butterflies, marine molluscs, migratory birds and plants are consistent with patterns of climate change seen in the UK over the past 30 years. Climate change response will be one factor driving natural range extensions of species.

Examples of invasive species

  • Aquatic plants: eg. The water primrose (Ludwigia grandiflora) Ludwigia which is currently unmanageable in France , is an aquatic plant native to South America .  It can spread rapidly and the very dense mats which it forms can present a threat to many aquatic species by depriving the submerged plants below of light, causing problems for aquatic invertebrates, clogging waterways and exacerbating flooding risks. It can lead to more algal growth in more static water and crowd out the space needed by fish.  It may also provide perches for cormorants and herons, leading to increased predation.

In 2006, Defra commissioned the Centre for Ecology and Hydrology to trial methods to eradicate the weed (helped by the Environment Agency).  The signs are that as the trial continues the "problem" is diminishing and complete eradication may well be feasible.  More information is available on the following Defra Focus story http://www.defra.gov.uk/news/issues/2007/environ-0102.htm

  • Japanese Knotweed: Japanese knotweed is native to Japan, Taiwan and China, and was introduced to Europe as an ornamental plant in the early 19th century. It is a large vigorous weed that appears to have no natural enemies in Britain. It can colonise most habitats and is regarded as a troublesome pest in many parts of the country because of its rapid invasion and domination of habitats, which results in the exclusion of other plants. Read on here.
  • North American Ruddy Duck: Information on the Ruddy duck can be found at http://www.csl.gov.uk/aboutCsl/portals/government.cfm
  • Grey Squirrels : The grey squirrel was introduced into this country from North America in the 19th century and has spread widely, especially in lowland areas, with a population now estimated at over 2 million. They are regarded as pests by a number of groups because of the damage they cause to woodland. They are largely responsible for the decline of the red squirrel in England because they are stronger and more adaptable than the red and they carry the Squirrelpox virus, which is lethal to red squirrels. More information is available on the following Defra News Release http://www.defra.gov.uk/news/latest/2006/wildlife-0123.htm
  • Signal crayfish: Introduced non-native fish such as Zander and signal crayfish can have direct effects on native species, for example by predation, or can upset the natural ecological balance. Non-native fish can also introduce novel diseases and parasites to which our native populations may have no resistance. In addition to the 1981 Act, further legal controls on the keeping of non-native crayfish were implemented in 1996. In England and Wales, The Prohibition of Keeping of Live Fish (Crayfish) Order 1996 was made as an Order under the Import of Live Fish (England and Wales) Act 1980. See the efishbusiness website and information on non-native fish and crayfish.

See also:

Page last modified: 26 November 2007
Page published: 26 May 2005

Department for Environment, Food and Rural Affairs