Assessing the impacts of development

There are two ways to find out whether there are red squirrels on your site:

• desk-based collation of known records or
• site-based survey

Known records

Records can be stored in a number of places. However, the most likely places to find these are in Local Record Centres    or through the NBN Gateway  . Further information may be available through local projects and links to the three main Scottish projects are on the right.  It is worth bearing in mind, however, that biological recording is largely dependent on volunteers and a lack of available records may just reflect a lack of recorders. Depending on the location of the site, you may still require survey evidence to show the effort you have made to identify whether red squirrels are in the area.

Site-survey

If there are no current paper records of red squirrels available, site survey should still be considered if:

• there are records from the area within the last 10 years and the habitat remains suitable; or
• there are current records of red squirrels in adjacent/surrounding woodlands.

If this survey does not find signs or dreys, this should be recorded as evidence in the report/application.

If there is evidence of red squirrels on-site, survey is important where there are plans to remove trees which have a reasonable chance of supporting dreys.  This includes conifer species, broadleaf and mixed woodland (including community woodlands and parklands). In areas with both red and grey squirrels, red squirrels are more likely to be found in areas of small-seeded species (including conifers).  Trees of less than 15 years old are less likely to have resident red squirrels as they will not produce a significant seed crop.

Site survey

There are a number of ways to survey for squirrels which are set out in Forestry Commission Practice Note 11  .  The main methods used to detect presence/absence are transect surveys and hair tube surveys although camera trapping may be an option where evidence of occupation of individual dreys is required.  The licensing requirements for this should be discussed with SNH.  Regardless of the method used, it is important to ensure that any work undertaken is proportionate but informative.  When approaching survey as part of development planning:

• ensure that the surveyor contracted to do the work has relevant experience or qualifications.  Further information on this can be obtained from the Institute of Ecology and Environmental Managers  ;
• conduct surveys well in advance of any planned work and at a time of year which will provide the best opportunity to record the species. Although red squirrels are active all year, late autumn is a prime period when day length is still long but trees are losing their leaves and animals are more likely to be visible through the canopy;
• conduct surveys at least four times over a period of two weeks. The dates and time of these surveys should be recorded in the Environmental Statement;
• depending on the scale of operations, the area covered by survey should be representative of the whole site and the adjacent area. Some judgement will be required for each case but 50m is the buffer zone within which there should be no disturbance to a breeding drey. On that basis, we recommend that survey should extend at least 50m from the edge of any proposed operational site;
• The survey needs to determine conclusively whether there are red squirrel dreys present on site and, if so, where these are. This information should be presented on a map at 1:500 scale;
• All attempts to collect evidence of red squirrels should be recorded.

Where work is planned in an area with both red and grey squirrels, any evidence of grey squirrels in or around the site should also be recorded and reported as this may influence the type of mitigation possible.