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Protected Species Surveys – Mammals

A number of mammals have legal protection under the Wildlife and Countryside Act 1981 (as amended) due to population declines or persecution. Under this legislation, it is an offence to intentionally kill, maim or take any of these animals, or to damage or destroy any place used for shelter or breeding. These protected species include water voles, otters, red squirrels, pine martens and badgers.

Due to this level of protection, a Protected Species Survey is usually required as part of a planning application. These surveys determine the presence or absence of any protected species on, or immediately next to, a site proposed for development. Consequently, mitigation measures can be put in place, or disturbance licences obtained, if necessary.

Otter Surveys

Otters are classed as a ‘specially protected wild animal’ under UK law and are a European protected species. It is an offence to injure, kill or take an otter and to disturb a breeding or resting site.

An initial survey will usually be carried out at a potential development site to assess the likelihood of otter presence. More in-depth licenced surveys follow. These search for various tracks and signs such as: droppings (spraints), footprints, feeding remains, holts, slides and couches (daytime resting spots).

Because otters are shy and largely nocturnal (at least in England and Wales), camera traps are also extremely useful when surveying otters. Spring is the best time for otter surveys as footprints are usually easier to find due to lower water levels.


Badger Surveys

Badgers have additional protection under the Protection of Badgers Act 1992. This makes it an offence to intentionally kill, injure or take a badger, dig for one, intentionally destroy or disturb a sett or send a dog into a sett.

It can be possible to obtain a licence to carry out certain activities in some circumstances, such as if a sett exists at a potential road or housing development site.

Survey techniques include the identification of setts, latrines, snuffle holes (signs of feeding) and tracks. Camera traps are again useful and can help determine the number of animals using a sett.

Water Vole Surveys

Protected under the Wildlife and Countryside Act, water voles are also a Priority Species under the UK Post-2010 Biodiversity Framework. This is due to serious declines caused by habitat loss and predation by escaped American mink. As with other protected species, it is illegal to intentionally kill, injure or capture one and to damage, disturb or obstruct a burrow.

Water vole surveys look for telltale signs along water courses. These include latrines, feeding sites, footprints and runways and burrows. If water voles are present, it is necessary to ensure work is not carried out within a certain distance of the courses. If this is not possible, licenced ecologists have the option of applying for a licence to displace or translocate the animals.

Water vole

Pine Marten Surveys

Pine martens are likewise protected under the WCA 1981 (as amended), and a licence is required to carry out certain actions that would otherwise be an offence. This includes development activities where they are present. Numbers crashed following extensive persecution in the 19th century but have been on the rise since the early 2000s and their range is extending from the Scottish Highlands.

If a site has the potential for pine martens, the main survey method used is to look for droppings, in conjunction with the use of camera traps. Pine martens are shy and predominantly nocturnal but tend to be more active during the summer, giving more potential for actual sightings.

Red Squirrel Surveys

The WCA 1981 gives red squirrels and their dreys (nests) full protection from intentional or reckless harm and disturbance. Approximately 75% of the UK’s red squirrels now live in Scotland. Their biggest threat is the non-native grey squirrel, introduced from North America in Victorian times. As well as outcompeting the smaller reds, greys brought with them diseases such as squirrelpox which have proved fatal to red squirrels in the UK.

Red squirrel surveys will look for the animals themselves, as well as their dreys. Drey numbers will indicate squirrel densities over a season. They are easiest to count over winter when leaf cover has gone. Feeding remains can also be looked for. When squirrels eat hazelnuts they cut them neatly in half, whereas they will leave a characteristic core when eating pine cones.

If there is a potential for grey squirrels to be present, then care needs to be taken to ascertain which species is present. Hair-tube surveys use sticky tapes to obtain hair samples that can then be inspected under a microscope to determine species.

Red squirrel