Forthbank Wind Energy Development - Partnerships for Renewables

Forthbank Wind Energy Development
Otter Survey: Methodology
11.2.44 The otter survey was undertaken by two RPS ecologists on 7 May 2010. The survey involved
systematically searching for otter field signs (see below for details) and included all areas of
suitable habitat (e.g. watercourses, waterbodies, coastal margins and associated terrestrial
habitats) within 500m of the application area as requested by Clackmannanshire Council 23 .
This survey distance exceeds the standard 250m survey area advised by SNH in its on-line
otter survey guidance 5 .
11.2.45 The only exceptions to the coverage of the survey were;
• the exclusion of habitats on the eastern side of the Black Devon (the opposite side
of the watercourse from the proposed wind energy development site); and,
• areas of dense, tussocky grassland located over 100m from the northern boundary
of the proposed wind energy development site.
11.2.46 The reasoning for these exceptions is explained below.
11.2.47 The land on the opposite side of the Black Devon is dominated by an open landscape of arable
fields with occasional minor drainage ditches situated behind the protective coastal defence
embankments of the Forth Estuary and the Black Devon. Although it was considered likely
that otters would occupy this side of the river, the habitat was largely considered to be suboptimal
for otters, particularly in terms of the availability of suitable habitat for resting sites (e.g.
holts). In addition, this part of the survey area was considered to be sufficiently segregated
from the development site such that otters would be unlikely to be affected by any proposed
works. Furthermore, the few areas which were considered to provide suitable habitat for
resting sites (e.g. isolated scrub) were located over 50m from the application area and
therefore beyond the maximum critical distance within which a European Protected Species
licence for otters would be required from the Scottish Government.
11.2.48 With regard to the dense, tussocky grassland to the north of the application area, the density
and extent of this expansive grassland habitat was such that it was considered extremely
unlikely that any otter evidence, let alone potential resting sites (i.e. couches, the suitability and
potential for holts to be present was negligible) would be discovered. Therefore, the survey
focussed on all areas located within 100m of the northern boundary of the application area.
This was considered sufficient since any resting sites located beyond this survey area would
be beyond the critical 50m distance for which a European Protected Species licence for otters
would be required from the Scottish Government.
11.2.49 The otter survey area is shown in Figure 11.3.
11.2.50 During the survey, evidence of otter presence and activity was recorded and mapped. Otter
field signs are described in Bang & Dahlstrøm 24 and SNH (2008) 5 , and include:
• holts;
• couches;
November 2010 Chapter 11 Page 9
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