Almost everybody knows something about otters and has some knowledge of what they are, that they live in water and eat fish, but most people have never seen one in the wild or at best only once or twice.
At the beginning of the 20th century the otter was present and relatively abundant in just about every part of Europe, then in the 1930’s their populations started to decline and by the 1950’s – 1960’s the decline had become quite rapid with them having disappeared completely from 60 departments in France. The populations continued to weaken into the 1980’s until eventually they only remained on the Atlantic coast and in the Massif Central. Since the 1990's the situation improved, starting with a gradual re-colonisation that gathered pace as they expanded again. Importantly fragmented groups have joined up to improve the genetic mix.
The situation in the rest of Europe followed a similar pattern with probable near extinction in Holland and Switzerland, Italy, Belgium and Luxembourg. The U.K saw similar declines but following conservation initiatives including cleaner rivers they have bounced back there as well.
The decline resulted from a number of factors, many of which have been the cause of serious harm to other species.
Traditionally otters have been a victims of persecution from hunting and trapping, hopefully this practice has almost ceased! Anyone known to be harming otters or any other protected species should be immediately reported to the Gendarmerie or the ONCFS
Pollution has been and continues to be a major threat to the health of otters the main dangers being organochlorines dieldrin, polychlorinated biphenyls and mercury (industrial pollution). Coastal populations are at risk from oil spills (accidents and flushing of ships tanks). Organic pollution from nitrates and slurry (agricultural pollution).
Strangulation and drowning both in fishing nets and in traps designed to kill other species.
Road building is a major problem; many otters are killed by traffic when new roads are built in their territory (77% of known deaths in the Central West of France).
Habitat loss from drainage and drying up of large ponds / lakes and waterways, river bank "improvements" and farming right up to the edge of rivers etc. bank side vegetation being very important. Poisoning may also be a factor.
Other than when mating for a period of perhaps two or three weeks otters are solitary animals inhabiting rivers, streams, highland and lowland lakes and coastal areas. They are adaptable to salt water but this is usually correlated to the presence of freshwater . They have a requirement for dense bank side vegetation with the presence of holes in the river bank, cavities in the tree roots, piles of rocks and wood debris. An otter will often have a territory of 20 to 30 kilometres and not without good reason as the diet consists principally of fish; if it stayed in one place it could soon exhaust the food supply. They also prey on frogs, eels, crustaceans, small mammals, birds and insects, their diet varying with the seasons. Mating can take place at any time of the year and this is where the structure of the bank side has great importance for constructing a Holt. The young are born, usually 2 or 3, after a gestation period of about 60 days; they are born with closed eyes which will not open for about 5 weeks, they develop quite slowly being feed with the mothers’ milk. After about 7 weeks they will start to venture out a little and take solid food provided by the mother who will continue to milk feed up to 14 weeks. At this point they don’t know how to swim and often need to be dragged into the water by their mother, where they soon catch on and are quickly capturing their own food although they will remain with her for the next 12 to 14 months. Incidentally, an otter swims with its nose above the water, only staying under water for about 20 or 30 seconds when hunting. Sexual maturity is reached between 2 and 3 years for males and between 3 and 4 years for females and although an otter can live for up to 16 years in captivity, its life in the wild rarely exceeds 5 years.
Is the tide turning it favour of the otter?
Thanks to cleaner rivers, greater understanding from the angling community and commercial fish breeders they are recolonising their old territories and increasing their range year on year which is fantastic. Fully protected species.