Conserving Natura 2000 Rivers

The Eurasian Otter (Lutra lutra)
Otter, Environment Agency

The Eurasian (or European) otter population of western Europe underwent a widespread decline during the 20th century. The decline, and subsequent recovery, has been well documented in the UK, although less historical information is available for most other countries.

The situation in Europe was reviewed during the period of decline, showing that otters were rare or extinct in much of central Europe in a broad band extending from Italy across to central Spain in the south up to Sweden and southern Norway. 'Widespread' populations existed mainly in western areas (Portugal, Ireland, Scotland, and parts of Spain, France, Wales and England) or eastern areas (from Finland through to Greece).

A recent review found evidence of a recovery. This showed that, although European populations were still considered healthy and widespread in only a third of the 37 countries for which data were available, the number where they were believed to be increasing had gone up from 28% to 38%. The proportion where otters were believed to be threatened, declining, very rare or extinct had gone down from 40% to 22%.

There was a sudden and widespread decline in the success of otter hunts throughout much of England and Wales in 1978, which corresponded closely with a perceived decline in the otter population from the mid 1950s. This was similar to changes observed in populations of various species of predatory birds and mammals and probably had the same cause - the introduction of cyclodiene pesticides (dieldrin and related compounds) in the mid-1950s. These pesticides were withdrawn from use in the UK in the 1970s.

Since 1977, as a result of a series of national otter surveys, substantial parts of England, Wales and Scotland have been surveyed three times, Ireland once and parts of it twice. In England and Ireland alternate 50 km squares were searched, in Wales and Scotland the whole land area was covered. These surveys involved recording the presence or absence of otter signs (usually their faeces, known as spraints) according to a protocol which has been widely used in Europe. In addition, the coast of the Shetland Islands has been surveyed twice by a different method involving the counting of active otter holts. Spraint surveys only provide information on distribution, while the holt surveys, which can only be used in certain coastal areas, provided estimates of the population.

Ecology of the European Otter

Monitoring the Otter

Otter Breeding Sites: Conservation and Management






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Environment Agency
Otter, Paul Glendell/English Nature
Paul Glendell/English Nature
Otter, Paul Glendell/English Nature
Paul Glendell/English Nature