Page 5 - Conservation Impact Report 2016

Conservation Impact Figure 1. Silver-washed fritillary population
trend at a nature reserve colonised in 2009
■■ Management of woodland rides has provided
the ideal ecological requirements for woodland (r=0.79, P=6.7E-05)
butterflies such as silver-washed fritillary (Argynnis
paphia). 15 woodland nature reserves support
populations of silver-washed fritillaries. 13%
are new populations with these sites being
colonised since 2002. 93% of silver-washed fritillary
populations are either increasing or stable (see
Figure 1).

■■ 6 woodland nature reserves support dormice
(Muscardinus avellanariu) populations. Population
trends are mixed across these sites. The
introduction of an active coppice regime at one
site has resulted in a population increase (mean
number of dormice per box was 0.005 in 2006,
and 0.074 2015). Other populations on sites with
similar management interventions are in decline.
This is possibly as a result of wetter, milder winters
(driven by climate change) increasing hibernation
mortality.

■■ Willow warbler (Phylloscopus trochilus) populations
on woodland nature reserves have remained stable
between 2007 and 2015.

Silver-washed fritillary

7 Woodland Area Stats 2010, Forestry Commission, www.forestry.gov.uk/pdf/NFI England_woodland_area_stats_2010_FINAL.pdf
8 UK Woodland Habitats, Joint Nature Conservation Committee, 2013, http://jncc.defra.gov.uk/page-1437, (accessed 12 March 2016)
9 C. Hambler, Evidence-based or Evidence-blind? Priorities for Revitalising Conservation, 2015, ECOS 36(3/4) p. 22 – 25.
10 The State of the UK’s Butterflies 2015, Butterfly Conservation, 2015
11 The Breeding Bird Survey 2015, British Trust for Ornothology
12 S. Harris et al., A Review of British Mammals: Population Estimates and Conservation Status of British Mammals Other Than Cetaceans, JNCC, 1995
13 D.B. Hayhow et al., State of Nature 2016, The State of Nature Partnership, 2016

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