Otter – Lutra lutra

Otter – Lutra lutra

Otters are warm blooded predators usually associated with rivers and other water bodes, including coastal areas. They are widely distributed in Europe although they underwent a significant decline (due to toxic effects of pesticides such as PCBs and habitat loss) in most European countries in the 1950s. There has been a subsequent revival in otter populations in some countries (e.g. UK) due to a number of factors including the recovery of fish stock stocks on which they depend for food.

Births are recorded throughout the year although some studies indicate that birthing occurs most often from November to January. Average litter sizes range from 2 to 3 cubs.

Riparian habitat is considered to be of key importance to most otter populations and its loss has been implicated in the decline of otter in the UK. The importance of riparian habitat on mainland areas may in part be due to improved food production as well as for breeding areas. Fish dominate in the diet of otters in most places, with crayfish and frogs occurring in the diet in lesser frequencies. A number of studies have found that juvenile salmon and adult salmon form an important part of their diet in some river systems. The rehabilitation of channels should improve otter populations through improving habitat quality and their food supply as fish stocks recover.

The IRD Duhallow LIFE + Project is currently working with Waterford Institute of Technology who are performing DNA analysis on Otter spraints (droppings) found along the catchment. The information gained from this state of the art technology can inform the team on aspects such as sex and range of individual otters within the catchment. this valuable information can then be used for future management of the riparian habitat.