Water Vole, Otter and Crayfish Surveys

Watercourse in Warwickshire

Should there be a suitable watercourse within or adjacent to the site, then a survey of this feature may be necessary. This involves the ecologist assessing the watercourse and its banks both 150m upstream and downstream for evidence of water vole burrows, latrines and feeding remains; possible otter holts or resting places, as well as crayfish burrows. DNA testing of droppings is another technique available, as well as the use of remote camera traps.

Otter surveys can be carried out at any time of year, whereas water vole surveys are best undertaken May-October when the animals are more active. Surveys for crayfish are best undertaken July-September.