west weald landscape project conference: pearl-bordered fritillaries
Post on 14-Jun-2015
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South Downs National Park Authority
A species on the brink
Pearl-bordered Fritillary
Dan HoareButterfly Conservation
70% of butterflies are in decline
Thomas, J.A. et al. 2004, Science 303, 1879.
Datasets from last 20-40 years
Habitat specialists (blue) and wider countryside species (red)
Woodland (green) and farmland (brown)
Woodland butterflies by habitat
0
50
100
150
200
250
1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009
Inde
x (1
985
= 10
0)
Rides
Clearings
Mature
All
-80%
Pearl-bordered Fritillary
Declining abundance
• 66% population decline since 1976
• 46% decline from 1995-9 to 2005-9
Declining distribution
• 61% distribution decline 1970-2004
• 43% decline in occupied 10km squares in 10 years
South East colonies since 1995
South East colonies
• 12 established sites (more than 50 extinctions since 1990s)
• 2 recent colonisations on chalk grassland
• 3 ongoing reintroductions
Landscape boundary
Woodland sites
Landscape-scale species conservation
Landscape boundary
Unmanaged 2007
Managed 2007
Tytherley Woods 2007
Landscape boundary
Unmanaged 2007
Managed 2007
Pearl-bordered Fritillary 2007
Pearl-bordered Fritillary 2007
Landscape boundary
Unmanaged 2007
Managed 2007
Pearl-bordered Fritillary 2007
2km focal area around colonies
Targeted management 2007-11
Landscape boundaryLandscape boundary
Unmanaged 2010
Managed 2010
Pearl-bordered Fritillary 2007
2km focal area around colonies
Targeted management 2007-11
Pearl-bordered Fritillary colonisations 2008-2011
Landscape boundary
Unmanaged 2010
Managed 2010
Pearl-bordered Fritillary 2007
2km focal area around colonies
Colonisations 2008-11
South East colonies• species can be brought
back from the brink with targeted effort
• species responses demonstrate the success of habitat management
• but it takes a lot of effort...
Biological Records Centre
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