Otters are medium sized semi-aquatic carnivorous mammals that live along rivers, lakes and coasts. Often mistaken for mink, they are larger, with brown fur and a pale underside. During the 1950s, otters suffered a significant decline from use of cyclodiene pesticides which bioaccumulated in the food chain (they mainly eat fish and amphibians). However populations have begun to recover in some areas and they can be spotted swimming and hunting in riparian habitats throughout the country.
Otters are fully protected under the Wildlife and Countryside Act (1981) (amended) and The Conservation of Habitats and Species Regulations (2017). This makes it an offence to kill or injure otters as well as disturb them or destroy their place of rest (i.e. habitat).Discuss your project with us
While rivers are most often thought of as the typical river habitat, they may also be found lakes, streams, coastal areas or even ditches connecting habitat. As well, the riparian habitat along the banks is very important and can include woodland, grassland, scrub, bogs, reed beds or any other vegetated habitat along the water. Otters will often walk along the river banks rather than in the water while traveling so any development along the river (particularly roads and bridges) can inhibit their range. Otter holts (dens) or couches area also usually found within the riparian habitat rather than in the water itself. Both the water bodies and the surrounding riparian areas are important for otter survival.
If the Phase I survey has identified habitat that may be used by otters, further surveying may be required if there is any potential for this habitat to be impacted. Given the large range for an individual otter (35km for males and 20km for females), it can be difficult to determine presence or absence. Otters will also use different areas of their range at different times of the season dependent on water levels, food availability and riparian habitat requirements. For this reason, surveys are undertaken at different times of the year within the appropriate season and using a variety of techniques.
Survey techniques can include use of remote camera traps and a visual search for holts/couches, tracks (in mud and sand banks) and spraints (sites for droppings). Searching for spraints is one of the most frequently used techniques as otters will mark out their range with spraints on bridge arches, rocks, ledges, tree roost etc. to protect their territory from other otters of the same sex (although otters of different sexes may overlap their range). Surveys are done multiple times over a year to cover different time periods and there should be at least five days without rain preceding the survey so that evidence is not washed away.
If possible, any resting places (holts) of otters should not be disturbed during developments. If this is not possible, a European Protected Species licence will be required from Natural England and a detailed strategy of mitigation and compensation implemented. Ecosupport can create an appropriate Ecological Mitigation Plan for otters to inform your planning application.About European Protected Species Licence
Our team has experience in surveying for otters and can happily undertake Phase II surveys and create a suitable mitigation strategy to get your site through the planning application without any issues.