Landscape-scale conservation for butterflies and moths - Lessons from the UK
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Landscape-scale
conservation for
butterflies and moths
Lessons from the UK
Landscape-scale conservation for butterflies and moths | 1
Landscape-scale conservation for butterflies and moths: lessons from the UK by Sam Ellis, Nigel Bourn and Caroline Bulman This report would not have been possible without the significant support of the national Government Agencies: Natural England, Scottish Natural Heritage and Countryside Council for Wales, as well as the Esmée Fairbairn Foundation, who together grant-aided the development of most of our landscape-scale projects. We are also indebted to the volunteers who have contributed to these projects, including those from some of Butterfly Conservation’s network of 31 Branches around the UK, but also from our many partner organisations. We are also grateful to all the landowners and land managers who have allowed Butterfly Conservation, its contractors and volunteers access to their land to enable project delivery. Special thanks are due to: Karen Aylward (Natural England), Norman Baldock (Dartmoor National Park Authority), Anja Borsje (previous Two Moors Threatened Butterfly ProjectOfficer, Butterfly Conservation), Gill Barter (Countryside Council for Wales), Steve Batt (Warwickshire Wildlife Trust), Frank Berney (University of Sunderland), Richard Boles (Forestry Commission England), Rona Charles (North York Moors National Park Authority), Mike Clark, Paul Dunn (Glamorgan Heritage Coast), Mike Enfield (Kent Wildlife Trust), Scott Hand (Countryside Council for Wales), Alison Hawkins (Exmoor National Park Authority), David Heaver (Natural England), Saul Herbert (Natural England), Ian Hickman (Forestry Commission England), David Lambert (Bentley Wood Trust), Dave Liddle (Durham County Council), Andy Lees (Durham Biodiversity Partnership), Rob Petley-Jones (Natural England), John Randall (Butterfly Conservation Devon Branch), Dave Rogers (Natural England), Phil Rudlin (Forestry Commission England), Dave Sheppard (Natural England), Pete Stevens (Natural England), Dan Tuson (Natural England), Michael Walter (RSPB), Mike Williams (Butterfly Conservation West Midlands Branch), Matt Wilmott (Natural England), John Wilson (Kent Wildlife Trust), Andrew Windrum (Natural England) and Rosemary Winnall (Wyre Forest Study Group). Thanks to all the contributing authors, project staff, Martin Warren, Mark Parson and Tom Brereton for comments on the text. Butterfly monitoring data was provided and analysed by Ian Middlebrook and Tom Brereton. The Marsh Fritillary butterfly distribution map was produced by Jim Asher and Richard Fox. Thanks also to Natalie Ngo for proof reading the text. Copyright © Butterfly Conservation 2012 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, mechanical, photocopying, recording or otherwise, without prior permission of the publishers. ISBN 13 978-0-9568935-1-2 This report should be cited as: Ellis, S., Bourn, N. A. D. and Bulman, C. R. (2012) Landscape-scale conservation for butterflies and moths: lessons from the UK Butterfly Conservation, Wareham, Dorset. Each section is also individually authored. Cover images: Norman Baldock, Sam Ellis, Robert Thompson and Jim Asher. 2 | Landscape-scale conservation for butterflies and moths
Contents
Foreword 4 High Brown Fritillary in the Vale of
Glamorgan: saving the last site
Executive summary 5 in Wales 52
Introduction: Butterfly Conservation Restoration of a Small Blue
and landscape-scale conservation 6 metapopulation on the Southam
Lias Grasslands of Warwickshire 58
Restoring Marsh Fritillary
metapopulations on Dartmoor 10 Landscape-scale woodland
restoration for multiple species
Conserving the High Brown Fritillary in the South East Woodlands 66
on the Morecambe Bay Limestones 16
Delivering land management
Conserving the Marsh Fritillary in advice for Marsh Fritillary
Dorset: Lessons from 15 years of in Scotland 76
landscape-scale conservation 24
Targeting restoration management
The impact of management on to stabilise Duke of Burgundy
Pearl-bordered Fritillary populations metapopulations on the
in the Wyre Forest 30 North York Moors 80
Specialist moths in Breckland: Discussion: Lessons from
creating bare ground habitat on landscape-scale conservation 86
a landscape-scale 36
References 92
The Heath Fritillary in the
Blean Woods: A low input large Acknowledgements 94
output landscape project 42
Restoring very small fragmented
landscapes for the Small
Pearl-bordered Fritillary in the
Durham Coalfield Pennine Fringe 48
Landscape-scale conservation for butterflies and moths | 3
Foreword
Sir John Lawton
to name but two. Butterflies, by conservation. It wasn’t a new insight.
the way, feature prominently in the Butterfly Conservation has used
evidence base summarised in Making metapopulation science to build
Space, both the successes, and landscape projects that are species
the ongoing declines of many once led, but which necessitate conserving
widespread species. The declines whole landscapes, and habitats within
fall disproportionately on the habitat those landscapes. These projects
specialists that require coppiced are designed exactly to create
woodland, grazed chalk grasslands, “more, bigger, better and joined” for
and so on. I don’t need to spell the Lepidoptera, primarily butterflies, but
issues out for this audience. also (as is clear from this report) for
What is driving the ongoing moths.
declines of so many species? Making The report summarizes over 10
Space concluded that there are four years of experience in delivering
main reasons. First, many protected “more, bigger, better and joined” at
sites are simply too small; 77% of sites across the UK. It is also timely.
SSSIs and 98% of Local Wildlife The lessons learned come at a time
Sites in England are less than when the landscape approach is a
Sir John Lawton 100 ha, too small to prevent random central plank of the Government’s
fluctuations driving local populations new Biodiversity 2020 strategy
Chairing the panel that produced to extinction. Only a tiny remnant and is being rolled out on a wider
Making Space for Nature between of some habitats remain, and many scale, for example in the 12 Nature
2009 and September 2010 (the surviving patches of semi-natural Improvement Areas that came out of
‘Lawton Report’) was one of the most habitat are poorly managed, or not the 2011 Natural Environment White
interesting things I have done in the managed at all. And finally many Paper The Natural Choice, part of
voluntary conservation sector. surviving sites are isolated in a sea Government’s response to Making
It was also one of the most of inhospitable agricultural or urban Space. And last, but absolutely not
depressing, because despite huge landscapes. Butterflies have played least, the report shows what can be
efforts by both the statutory and a vital role in developing and testing achieved through a highly focused
voluntary sectors, particularly since the science of metapopulation species-led approach. Very simply
the end of the Second World War, dynamics that shows so clearly why “more bigger, better and joined”
Making Space concluded that this combination of four factors can works, and needs to be rolled out
England’s protected area network have such devastating consequences far more widely, because, of course,
was still not preventing the continuing for species unable to easily disperse recreating, restoring and joining up
declines of many species of plants and that require specialised habitats. habitats benefits not just butterflies
and animals, some of them truly Although Making Space dealt only and moths, but a host of other
alarming. This is absolutely not to with England, much the same creatures with which they share their
say that conservation efforts have arguments apply to the Devolved habitat.
been a waste of time; I shudder to Administrations. For all these reasons I commend
think how much worse things would The solution? The ‘executive this excellent and timely report and
have been without those efforts! summary’ of Making Space was thank the funders for their vision and
And of course there have been blindingly simple. We need “more, support.
some real successes. It isn’t all bad bigger, better managed and
news. Red Kites are back in force, joined up” sites in a landscape Sir John Lawton
and Large Blue butterflies flourish, level approach to wildlife York, July 2012
4 | Landscape-scale conservation for butterflies and moths
Executive summary
1. Butterflies remain one of the UK’s 5. The publication of this report III. Skilled project officers are an
most threatened wildlife groups, with is timely as recent government essential component of effective
three-quarters of species declining initiatives such as Making Space for landscape-scale conservation,
in either distribution or population Nature (Lawton, 2010), have called providing the link between
during the 10-year period 1995-99 to for widespread use of landscape- landowners and managers, partner
2005-09 (Fox et al., 2011). scale conservation. The principles are organisations, grant schemes and
embedded in the UK Government’s other funding sources, contractors
2. The science of metapopulation recent white paper, The natural and volunteers.
biology has increased our choice: securing the value of nature
understanding of how butterfly and Defra’s updated biodiversity IV. Landscape-scale projects
populations persist within strategy Biodiversity 2020: A strategy must be underpinned by sound
landscapes. In response Butterfly for England’s wildlife and ecosystem ecological research, their design
Conservation has shifted the majority services (Defra, 2011). supported by good quality spatial
of its conservation work during the data and their effectiveness
last decade from a focus on single 6. This report describes 12 measured by a suitable monitoring
sites to targeting networks of sites evidence-based case studies from system.
across a landscape. around the UK of landscape-scale
conservation targeted at threatened V. Butterflies and moths respond
3. Butterfly Conservation defines butterflies and moths. For each case very rapidly to landscape-scale
landscape-scale conservation as study we describe the landscape, conservation and projects focused
the coordinated conservation and the habitat requirements of the on a single butterfly or moth can
management of habitats for a range of target species, the project delivery and do benefit a suite of other
species across a large natural area, mechanisms, funding sources, land species which have broadly similar
often made up of a network of sites management outcomes and species habitat requirements.
(Bourn and Bulman, 2005). responses.
VI. Short-term funding (e.g. Landfill
4. Area and isolation of habitat 7. Some common themes emerge Communities Fund) is invaluable for
patches are vital factors in ensuring from our experiences delivering the restoration phase of landscape-
species survival across a landscape landscape-scale conservation. We scale projects, but well designed
(Hanski, 1999). However, research believe the key wider lessons relevant agri-environment and woodland
suggests that because rare species to the conservation of wildlife at the grant schemes are not only a key
are restricted to very specific habitats landscape-scale are: delivery mechanism but a very
or niches, it is just as important to effective means of sustaining project
maintain high quality habitat within I. Species conservation can be very outcomes.
individual sites, as to maintain the site effective at the landscape-scale, but
network (Thomas et al., 2001). careful targeting of management, VII. The maintenance of existing
both across the site network and high quality habitat is more cost
within each site, is essential to effective in the long run than
maximise the chances of success. restoration management.
II. Extinction of species on small, VIII. Landscape-scale conservation
isolated sites need not be inevitable always involves partnership
if they are properly managed and working, but must be developed
the principles of landscape-scale through a shared vision and action
conservation can be applied at on the ground.
relatively small spatial scales.
Landscape-scale conservation for butterflies and moths | 5
Introduction: Butterfly Conservation
and landscape-scale conservation
the way that populations persist
Neil Hulme
within these dynamic landscapes.
The science of metapopulation
biology has subsequently developed
understanding of how individuals
move between habitat patches within
a landscape; as well as the effect of
increasing isolation, changes in patch
size and quality and the incidence of
extinction and colonisation (Hanski
1998). Butterfly populations became
the main study system for this
influential research and Butterfly
Conservation responded by shifting
the majority of its conservation work
from a focus on single sites, to
targeting networks of sites across a
landscape. This report describes
case studies of such projects and
identifies wider lessons that are
relevant to the implementation of
landscape-scale conservation.
The metapopulation concept can
High Brown Fritillary, the UK’s fastest Butterflies are still in serious decline
be thought of as a ‘population of
declining butterfly and remain one of the UK’s most
populations’, occupying islands of
threatened wildlife groups. The
habitat within a ‘sea’ of unsuitable
results from Butterfly Conservation’s
habitat. This clearly describes the
most recent analysis (Fox et al., 2011)
countryside we see in Britain today,
show that between 1995-99 and
where areas of remnant habitat, such
2005-09, 72% of species declined in
as chalk grassland, woodlands, wet
abundance (38 of 53 species
meadows etc, are surrounded by an
assessed) at monitored sites and the
agriculturally improved and
distributions of 54% of species also
developed landscape. The butterflies
declined during the same period (32
which inhabit these remnants tend to
of 59 species assessed). Overall
be the more specialist species that
three-quarters of butterfly species
are rapidly declining – they are more
declined in either distribution or
prone to local extinction due to low
population during this 10-year period
population size, natural fluctuations
(Figures 1 and 2).
and deteriorating habitat suitability. If
During the last century extensive
extinction occurs there is the potential
studies have been made on the
for recolonisation by individuals from
biology and ecology of butterflies
a nearby population. However, as
(and to a lesser extent moth species),
further habitat destruction and
making Lepidoptera one of the most
change takes place, these sites
widely understood insect groups.
become increasingly isolated,
With increasing destruction,
recolonisation becomes less likely
modification and fragmentation of our
and the metapopulation will be at
natural and semi-natural habitats
greater risk of extinction.
research has frequently focused on
6 | Landscape-scale conservation for butterflies and moths
Butterfly Conservation defines
landscape-scale conservation as
the coordinated conservation and
management of habitats for a range of
species across a large natural area,
often made up of a network of sites
(Bourn and Bulman, 2005).
Metapopulation theory has re-
orientated conservation priorities to
the landscape-scale by emphasising
the importance of area and isolation
(Hanski, 1999). However, research
suggests that because rare species
are restricted to very specific habitats
or niches, it is just as important to
maintain high quality habitat within
individual sites, as to maintain the
site network (Thomas et al., 2001).
This principle is central to Butterfly
Conservation’s approach to
landscape-scale conservation
delivery. Moreover, in the context of
climate change, a landscape-scale
approach appears to be the best
option for creating the habitat
heterogeneity likely to be needed for
species with changing ecological
requirements as well as providing the
opportunities for them to move
through the landscape.
The publication of this report is
very timely as recent government
initiatives such as Making Space for
Nature: A Review of England’s Wildlife Figure 1 Like many UK butterflies, the Marsh Fritillary has declined in distribution and
Sites and Ecological Network by Sir been lost from large parts of the country. During the most recent recording period, this
John Lawton (2010), have called for decline has slowed and even been reversed in some regions thanks to landscape-scale
widespread use of landscape-scale conservation initiatives
conservation. The principles are
140
embedded in the UK Government’s
recent white paper, The natural
Population index (1995=100)
120
choice: securing the value of nature
(TSO, 2011) and the recent updated 100
biodiversity strategy from DEFRA
(2011) Biodiversity 2020: A strategy 80
for England’s wildlife and ecosystem
60
services.
Landscape-scale conservation for
40
Lepidoptera in practice has two main
objectives. Firstly, to maximize 20
habitat quality within individual sites
by targeted management. This is no 0
different to managing a single site, 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
but at the landscape-scale more Figure 2 Evidence from the UK Butterfly Monitoring Scheme shows that butterfly
cognisance is taken of the spatial populations across the UK have undergone a significant decline of 29% since 1995
context of the individual sites. For
Landscape-scale conservation for butterflies and moths | 7
across the UK (Figure 3). These The main foci of these case
Martin Warren
projects have targeted key areas for studies are UK Biodiversity Action
some of the UK’s most threatened Plan (UK BAP) Priority Species
species, nearly all have received butterflies and their habitats: Small
some external funding, directly or Blue Cupido minimus, Duke of
indirectly, to enable delivery and all Burgundy Hamearis lucina, Small
involve partnerships with government Pearl-bordered Fritillary Boloria
agencies, other conservation selene, Pearl-bordered Fritillary
organisations and landowners. Boloria euphrosyne, High Brown
Broadly we utilise two Fritillary Argynnis adippe, Marsh
approaches to landscape-scale Fritillary Euphydryas aurinia and
conservation, firstly to provide advice Heath Fritillary Melitaea athalia. A
to landowners and encourage or group of Breckland moths are the
assist with the uptake of agri- focus of one case study, comprising
environment or woodland grant the Grey Carpet Lithostege griseata,
schemes; and secondly to secure Basil Thyme Case-bearer Coleophora
funding to directly undertake habitat tricolor, Lunar Yellow Underwing
management under the guidance of Noctua orbona, Forester Adscita
Butterfly Conservation project statices, Tawny Wave Scopula
officers. rubiginata and Marbled Clover
Butterflies and moths have precise These are not mutually exclusive Heliothis viriplaca. With the exception
ecological requirements that need to be with most projects having elements of Tawny Wave and Marbled Clover,
provided for in any landscape; such as of both approaches. these moths are also UK BAP Priority
for this High Brown Fritillary larva that
The need for evidence-based as Species. In England, all the BAP
requires violets growing within moderately
dense Bracken litter to provide a warm opposed to experience-based Priority Species are also listed under
microclimate conservation is now well recognised section 41 of the Natural Environment
(Pullin and Knight, 2001). We and Rural Communities Act (2006). In
example, sites at the centre of a describe here 12 case studies from Wales, the High Brown Fritillary is a
network may well be given higher around the UK which provide section 42 species of the Natural
priority for management than would a quantitative evidence of the lessons Environment and Rural Communities
small, isolated site on the network’s learnt from delivering landscape- Act (2006) and in Scotland, the
periphery. scale conservation over the last 15
The second major objective is to years. For all our landscape-scale
Martin Warren
improve connectivity both within and projects we try where resources
between sites, improving the ability of allow, to monitor the impact on not
butterflies and other organisms to just the target species, but on other
move around a landscape, thus wildlife and on habitat condition. For
increasing the rate of colonisation. Lepidoptera we adopt standard
Managing to improve connectivity monitoring methods appropriate to
involves the removal of barriers to the target species, such as species
dispersal (e.g. felling strategically occupancy (presence/absence within
located plantations or planting flower- a habitat patch or site), butterfly
rich margins). It can also include transects (full species weekly
management that improves habitat transects or single species transect
availability within the landscape (e.g. counts), adult timed counts, larval or
ride-widening). egg counts. Further details of these Britain’s landscapes consist of isolated
Since the turn of the millennium, methods are available on the UK fragments of semi-natural habitat
Butterfly Conservation has been Butterfly Monitoring Scheme website surrounded by intensively managed
involved to a greater or lesser extent (www.ukbms.org). land, as illustrated by this photograph of
with 73 landscape-scale projects downland in the south of England
8 | Landscape-scale conservation for butterflies and moths
Marsh Fritillary is a section 2.4 Butterfly Conservation landscape target areas
species of the Nature Conservation
(Scotland) Act (2004). The High
Brown Fritillary, Marsh Fritillary and
Heath Fritillary are fully protected by
the Wildlife & Countryside Act (1981).
The Marsh Fritillary is also protected
under Annex II of the European
Commission’s Habitats and Species
Directive.
For each case study we describe
the landscape, the target species and
a summary of its autecology and
habitat requirements. The project
delivery mechanisms and funding
sources are outlined, together with
the land management outcomes Mull, Lorne, Mid-Argyll
achieved to date. Species responses & Knapdale and Islay
to management are described: either Durham Coalfield
changes in site or habitat patch Pennine Fringe
occupancy, or population trends.
Responses of non-target Lepidoptera
are also reported where data are North York Moors
available.
Morecambe Bay Limestones
Community involvement in each
project (e.g. public events, training
and recruitment of volunteers) is a
crucial component of every Southam Lias Grasslands
landscape project and we describe
the contributions made to project The Brecks
delivery by volunteers. Finally we Wyre Forest
summarise the key successes and
lessons learnt from each project and
where relevant, plans to sustain the
project outcomes in the future. Alun Valley Blean Woods
Some common themes emerge
from our experiences of delivering
landscape-scale conservation for
threatened Lepidoptera across the
UK. We believe that sharing this
evidence has never been more Dartmoor Wessex Downs and South East Woodlands
important, and the final chapter Blackmore Vale
brings this together to help provide
lessons for conserving wildlife at a
© Crown Copyright and database rights [2012]. Ordnance Survey 100022021
landscape-scale.
Figure 3 Location of Butterfly Conservation’s 73 landscape target areas in the UK.
Landscapes with current or recently completed projects are highlighted dark green and
those with currently limited engagement or in a project development phase light green.
The locations of the 12 landscape-scale case studies are circled
Landscape-scale conservation for butterflies and moths | 9
Restoring Marsh Fritillary
metapopulations on Dartmoor
Jenny Plackett, Nigel Bourn and Caroline Bulman
The Marsh Fritillary is distributed
Steve Doyle
widely throughout Europe as far
eastwards as Korea in Asia, but
its range has declined seriously in
most European countries over the
last century (Swaay and Warren,
1999). The butterfly has declined
substantially in the UK and its
distribution in Britain declined by 46%
between 1970-82 and 1995-2004
(Asher et al., 2006). A more detailed
survey showed that 66% of colonies
in England were lost between 1990
and 2000 (Hobson et al., 2001). On
the positive side, many previously
unknown colonies have been
discovered over the last 20 years
(Fox et al., 2006) and during the last
ten years the distribution decline has
lessened to 9% (Fox et al., 2011).
Current strongholds for the butterfly
are the Culm grasslands of Devon
Marsh Fritillary and Cornwall, the Rhôs pastures of
Introduction South Wales and Dartmoor, damp
As the Marsh Fritillary Euphydryas grasslands of Argyll, and the chalk
aurinia is a species closely linked downland of Dorset and Wiltshire.
to extensive pastoral farming, the The Marsh Fritillary breeds in
main mechanism for its conservation
across the landscape is agri-
Jenny Plackett
environmental schemes. These are
designed to help farmers farm in
a more environmentally sensitive
way. Through the Two Moors
Threatened Butterfly project, Butterfly
Conservation has worked closely
with Natural England, the National
Park Authorities and the farming
communities of Dartmoor and
Exmoor to maximise biodiversity
delivery. The project demonstrates
the huge added value a targeted
scheme, backed with a strong
supportive presence on the ground,
can bring to our agri-environment
schemes. By working closely with the
local farmers whole landscapes can
be brought into a range of favourable
The Marsh Fritillary larval foodplant,
management options. Devil’s-bit Scabious, is responding well to
management
10 | Landscape-scale conservation for butterflies and mothsopen grassy habitats, especially
damp grassland dominated by
tussock-forming grasses; calcareous
grassland (usually on west or south-
facing slopes) and heath and mire
vegetation with Devil’s-bit Scabious
Succisa pratensis the larval foodplant
(Asher et al., 2001). The females
have a preference for laying egg
batches on foodplants growing within
a vegetation range of between 5
and 25 cm depending on the habitat
type – shorter swards on calcareous
sites and towards the upper range
on damp grasslands (Barnett and
Warren, 1995; Bulman, 2001).
Causes of the species decline © Crown Copyright and database rights [2012]. Ordnance Survey 100022021
over the last century include the Figure 1 Location of the four habitat networks on Dartmoor which support Marsh Fritillary
dramatic loss of unimproved colonies
grassland (e.g. 92% of South
dispersal, known as metapopulations
Jenny Plackett
West England’s damp pasture
and 60% of chalk downland) (Warren, 1994; Bulman, 2001;
following agricultural improvement Bulman et al., 2007)
and changes in the management On Dartmoor, lack of grazing is a
of remaining habitat fragments, common problem on Rhôs pasture
principally abandonment of grazing because the habitat offers low quality
and over-grazing (Hobson et grazing, which makes grazing of
al., 2001). The Marsh Fritillary is these marginal sites uneconomic.
typically associated with extensive Under-grazed, neglected or
grazing by cattle or ponies, which abandoned habitat patches quickly
create the varied turf required for become unsuitable for the butterfly,
breeding. Sheep grazing is generally as Western Gorse Ulex galli and
Marsh Fritillary larval web in late summer
unsuitable, as these animals tend willow Salix spp. scrub dominate and
to graze the foodplant too tightly the grass sward becomes rank and
and advice is offered in habitat
and create a more uniform sward overgrown, shading out foodplants.
management, accessing funding
(Warren, 1994). Sheep grazing also As habitat loses condition through
to pay for required works and help
heavily impacts on seed set (lack lack of management, connectivity
given liaising with contractors and
of flowers) and tends not to create within the landscape is reduced,
graziers.
the necessary small bare patches leaving the remaining patches
The project supports Natural
through moderate poaching to allow isolated and their Marsh Fritillary
England staff by assisting in agri-
new plants to colonise. colonies vulnerable.
environment applications and by
Marsh Fritillary populations The Two Moors partnership
ensuring appropriate management
function on a landscape-scale. project was initiated in 2005 to
prescriptions are included in the
They are often highly cyclical with reverse the declines of the Marsh
agreement terms. Training events
large fluctuations in population Fritillary, the High Brown Fritillary
are organised for conservation
size, making them prone to local Argynnis adippe and the Heath
professionals, landowners and
extinction, but this characteristic Fritillary Melitaea athalia across
contractors, and project staff work
also allows the butterfly to colonise Dartmoor and Exmoor. Habitat
closely with volunteers to undertake
new sites in good years as well as networks for targeting resources
practical management and species
patches of less suitable habitat. The at these species were identified,
monitoring. Guided walks and
butterfly persists in areas where large and project staff work closely
other public events are organised
networks of suitable habitat exist, with landowners to encourage
to increase understanding and
with groups of local populations sensitive management and increase
appreciation of butterflies.
being connected by occasional connectivity between sites. Support
Landscape-scale conservation for butterflies and moths | 11securing appropriate longer- the quality of breeding habitat.
Jenny Plackett
term management. Management Management of unoccupied as well
works have been funded through as occupied habitat was undertaken,
landowners’ agreements where to increase the area of potential
possible, or undertaken by volunteer breeding habitat and improve
parties if funding was unavailable. connectivity between patches. On
In the Fernworthy-Long Lane valley some habitat patches, no vegetation
system six of 20 habitat patches management was required other than
were known to be occupied by the the introduction of an appropriate
butterfly in 2005; 15 were ungrazed grazing regime. Grazing was re-
or inappropriately grazed (with introduced, or the grazing regime
unsuitable animals or at the wrong modified, on 15 patches grazed too
time of year), and in 16 habitat heavily or by unsuitable animals.
patches the open grassland habitat Over £100k in funding was
Volunteers clear scrub to restore Marsh was being invaded by willow and secured through agri-environment
Fritillary habitat condition Gorse scrub. The average distance scheme agreements and other
from any habitat patch (regardless of sources. This supported capital
The Marsh Fritillary is present at its occupancy state) to the nearest expenditure on fencing and scrub
only one Exmoor site, where the occupied patch was 542 m. control and provided landowners
butterfly has responded to Bracken Working with landowners and with area-based payments to graze
Pteridium aquilinum management, Natural England staff, the project their land with low numbers of hardy
rank grassland cutting and the has helped to secure Higher Level animals suited to this type of rough
reintroduction of sympathetic grazing. Stewardship (HLS) agreements at grassland at the appropriate time of
Dartmoor National Park is a national eight of the 15 farm holdings (on year.
stronghold for the species, where it which the 20 habitat patches are
is found in four separate networks, located), supporting appropriate Land management results
across the moor (Figure 1), including management over the 10-year Table 1 summarises the project’s
the Fernworthy-Long Lane valley agreement period. Capital Works achievements in terms of overall
described here as a case study. payments secured through this advice provision and management
The Fernworthy-Long Lane scheme, or the older Environmentally undertaken for nine habitat networks
network supports one of the most Sensitive Areas (ESA) scheme, across the two moors. Following
extensive area of potential habitat supported scrub control works advice from the project, 71% of
within the National Park, with 100 at a number of occupied habitat sites within Dartmoor’s four habitat
ha of Rhôs pasture, spread over 20 patches, and fencing/boundary networks have been managed for the
habitat patches on 15 different farm works were undertaken to enable Marsh Fritillary.
holdings (Figure 2). The system was grazing by hardy cattle or ponies In the Fernworthy-Long Lane
defined as a Prime Valley System to be reintroduced. Management of network, habitat improvement work
by Dartmoor National Park Authority other invading vegetation (Soft Rush carried out between 2005 and 2010
as part of their Rhôs pasture survey Juncus effusus, Greater Tussock- resulted in management of just over
undertaken during 1994-1996. These sedge Carex paniculata) was also 10 ha of land, including over 8 ha
Prime Valley Systems were the most carried out, and small areas of of scrub control. Nearly 5 km of
important wildlife areas within the woodland were felled and hedges fencing was erected or boundary
scope of the study and are a priority cut to create clear flight paths and improvements undertaken across
for conservation action. The extensive improve connectivity between habitat eight holdings in order to implement
area of Rhôs pasture habitat in this patches. On one patch with low an appropriate grazing regime (Table
system makes it a key target for frequency of the larval foodplant, 2). This management has both
landscape-scale restoration. young Devil’s-bit Scabious plant increased the area and improved the
plugs were transplanted from a quality of breeding habitat within the
Project methods nearby donor site by volunteers. valley system, as well as improving
Effort in the four Dartmoor On another patch, the landowner connectivity between patches.
habitat networks has focused on collected the seed from flower Between 2005 and 2010 the area of
encouraging landowners to enter heads and scattered it in another confirmed occupied habitat rose from
into agri-environment agreements, patch undergoing habitat restoration 32.9 ha to 85.6 ha.
elsewhere on the farm, to improve
12 | Landscape-scale conservation for butterflies and moths© Crown Copyright and database rights [2012]. Ordnance Survey 100022021
Figure 2 Map showing location of 15 farm holdings and changes in Marsh Fritillary patch occupancy 2005-10 in the Fernworthy-Long
Lane habitat network
800
Species response
Marsh Fritillary populations were 700
Fernworthy-Long Lane
monitored at a subset of sites in all habitat network
the habitat networks and at all sites 600
within the Fernworthy-Long Lane UK
Population index
500
valley during the adult flight period
using timed counts and autumn
400
larval web counts. Both sets of raw
data were adjusted to give number 300
recorded per person per hour. Within
the Fernworthy-Long Lane network 200
the number of occupied habitat
patches increased three-fold from 100
six confirmed in 2005 to 18 in 2010.
Connectivity has improved with 0
halving of the mean distance from 2005 2006 2007 2008 2009 2010
each patch to the nearest occupied
patch falling from 542 m to 260 m Figure 3 Marsh Fritillary larval web population trends in the Fernworthy-Long Lane habitat
network 2005-10. Data analysed by TRIM; UK national trend included for comparison
over the same period. This may be in
part due to the increase in recording
effort over the project period and abundance of larval webs between Building local partnerships
newly discovered colonies, with 2005 and 2010 in the network (Figure
Volunteer effort has been increasingly
eight habitat patches confirmed as 3), with the largest increases in 2009
important in achieving appropriate
occupied during 2010 monitoring, and 2010, following on from two
management in Rhôs pasture habitat,
which were not surveyed in 2005. particularly poor years in 2007 and
particularly during 2010. Cuts in
Overall there was a significant 2008, when wet and cool weather
agri-environment scheme support
increase of 1,082% (Ppatches managed
% habitat network
% habitat network
for fritillaries (ha)
advice provided
scrub managed
patches advice
Area managed
patches where
managed (ha)
provided (ha)
Area of scrub
managed for
for fritillaries
Area advice
No. habitat
No. habitat
No. habitat
area (ha)
provided
fritillaries
No. sites
species
Target
Total
Exmoor Heddon Valley HBF 15 68 15 68 14 66 12 15.1 100 97
Exmoor Exe Valley HBF 7 59 7 59 5 57 5 14 100 90
Exmoor Codsend Moor MF 3 79 3 79 3 79 0 0 100 100
Dartmoor Dart Valley HBF 10 138 9 108 9 108 6 8.2 78 78
Dartmoor Walkham Valley HBF 3 181 3 181 3 181 3 4.5 100 100
Dartmoor Tor Valley MF 7 58 6 47 6 47 3 2.6 81 81
Dartmoor Postbridge-West Webburn MF 20 218 17 183 14 173 6 4.9 84 79
Dartmoor Fernworthy-Long Lane MF 20 103 19 101 20 103 14 8.2 98 100
Dartmoor Tavy Valley MF 8 68 7 63 4 16.5 3 0.7 92 24
HBF, 74 894 19 499.5 11 6.4 56
Dartmoor & Exmoor Other areas
MF, HF
Total 160 1,783 97 1,330 63 72.3
Table 1 Summary of advice provision and management achievements across nine Exmoor and Dartmoor habitat networks 2005-11
MF = Marsh Fritillary; HBF = High Brown Fritillary; HF = Heath Fritillary
and students from Duchy College
Jenny Plackett
in Cornwall) have also given
considerable help in surveying and
practical management. During 2010,
for example, volunteers contributed
192 volunteer days on Marsh
Fritillary sites. Eight training events
and workshops in identification and
monitoring were attended by a total
of 87 people in 2010.
Key lessons
Agri-environmental schemes are a
key mechanism for the delivery of
targeted habitat management across
whole landscapes. They enable
significant levels of financial support
to farmers and landowners who
are often farming in economically
marginal areas. It allows them to
go the extra mile that conservation
land management often requires to
maximise the public benefits that
these schemes can offer. However, it
Volunteers plant out young Devil’s-bit Scabious plants to improve breeding habitat quality
is often the case that the full potential
of the scheme goes unrealised
more difficult to access funding been invaluable, and volunteers from due to insufficient support to the
to pay for important management local community conservation groups landowner, both in terms of further
works, so there has been a heavy (e.g. Chagford Conservation Group, advice and delivery of what are
reliance on volunteers to carry out the Wildlife Hit Squad from East often complex solutions to problems
practical habitat management. In Dartmoor Woods and Heaths NNR, that have been developing in these
particular, BTCV volunteers have South West Lakes Trust, Groundwork marginal areas for several decades.
14 | Landscape-scale conservation for butterflies and mothsRegular ‘care and maintenance’ visits continuing to work with landowners
Jenny Plackett
have been crucial to the success of across Dartmoor over the coming
the project, and of the Environmental years, offering advice and support, is
Stewardship Scheme, in achieving crucial to ensure that the successes
biodiversity gain. Most sites require gained so far can be sustained in the
several visits per year, when the long-term.
habitat is inspected and support Managing the habitat for the
and encouragement are offered to Marsh Fritillary has helped to maintain
maintain appropriate management. and restore habitat on a landscape-
Partnership working with Natural scale for other declining Lepidoptera,
England and the National Park, along such as the Narrow-bordered Bee
with volunteer organisations and Hawk-moth Hemaris tityus and Small
contractors, has helped to improve Pearl-bordered Fritillary Boloria
habitat quality and connectivity, and selene, as well as a wide range of
secure the appropriate management other flora and fauna found in wet
of Rhôs pasture in the Fernworthy- pastures.
Long Lane valley for the benefit of
Invading scrub and tall hedges have been the Marsh Fritillary and other wildlife.
cut back to improve connectivity between Maintaining these partnerships and
sites Holding 10
Holding 11
Holding 12
Holding 12
Holding 13
Holding 14
Holding 15
Holding 1
Holding 2
Holding 3
Holding 4
Holding 5
Holding 6
Holding 7
Holding 8
Holding 9
Total
No. of habitat patches 1 2 1 1 2 3 1 1 1 1 1 2 1 1 1 20
Habitat management Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes 14
advice given holdings
Support with entry to agri- No Yes No Yes Yes Yes Yes No Yes Yes Yes No No No No 8
agreement (in ESA) (in ESA) (in ESA) (in DNPA (in ESA)
environment scheme (HLS) agreement) holdings
Vegetation management
Total area of vegetation 1.1 0.3 0.5 3 0.35 0.8 1.31 0.1 0.4 0.3 0.21 0.35 0.8 0.1 0.4 10.02ha
managed
Scrub control 1.1 0.5 3 0.3 0.4 0.4 0.1 0.4 0.3 0.16 0.35 0.7 0.1 0.4 8.21ha
Soft Rush mowing/Bracken 0.3 0.3 0.66 0.01 1.27ha
control
Woodland felling 0.05 0.1 0.25 0.04 0.1 0.54ha
Grazing
Fencing/ boundary restoration 633m 450m 510m 226m 1292m 560m 202m 1010m 4883m
(350m
planned)
Total area managed 6.6 2.3 4.8 7 3.4 7.6 7.1 7 12 5.3 2.7 7 6 2.6 1.6 8.4 91.4ha
(1.3
by grazing (ha) planned)
Planting/sowing
Devil’s-bit Scabious (ha) 0.2 0.2 0.4ha
Changes in patch occupancy
Occupied in 2005 Yes Yes No Yes Yes NS No NS Yes NS NS NS NS NS Yes NS 6
(adults or webs) patches
Occupied in 2010 Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes Yes Yes Yes Yes Yes 18
(adults or webs) 2 sites 2 sites 2 sites patches
Increase in habitat 4.8 7.6 7.1 7 2.7 7 6 2.6 8.4 53.2ha
resource (ha)
Table 2 Summary of habitat management and changes in patch occupancy of Marsh Fritillary in the Fernworthy-Long Lane system 2005-10
NS = Not surveyed; DPNA = Dartmoor National Park Authority
Landscape-scale conservation for butterflies and moths | 15Conserving the High Brown Fritillary
on the Morecambe Bay Limestones
Sam Ellis, Dave Wainwright and Martin Wain
declines in both distribution (79%
Mike Hunter
between 1970-82 and 1995-2004)
and abundance (85% 1995-2004)
(Fox et al., 2006). This decline is
ongoing, with distribution losses of
49% and population declines of 69%
between 1995-99 and 2005-09 (Fox et
al., 2011). Several colonies still occur
on Dartmoor and Exmoor and one in
the Alun Valley in South Wales, but
the Morecambe Bay Limestones and
to a lesser extent, the South Cumbria
Low Fells to the north, are the UK’s
national stronghold supporting two-
thirds of the remaining populations.
Formerly the butterfly occurred
widely in woodland clearings,
probably where Bracken Pteridium
aquilinum was also present, but
breeding is now restricted to either
1) Bracken-dominated habitats or
grass/Bracken mosaics or
2) limestone rock outcrops, usually
where scrub or woodland has
recently been cleared or coppiced.
Only on the Morecambe Bay
High Brown Fritillary Introduction Limestones are rock outcrops
Most of our threatened butterflies used, with all other British sites
have very demanding ecological now confined to Bracken habitats.
requirements. For these species, Most Morecambe Bay Limestones
land management operates at a sites support a mosaic of habitats,
comparatively coarse scale and even with limestone or acid grassland,
with careful targeting the required pavement, Bracken, scrub and
habitat conditions may only be met woodland predominant.
within a subset of habitat patches Common Dog-violet Viola riviniana
or within a small proportion of a is the main larval foodplant. The High
given patch. We describe here the Brown Fritillary over-winters as eggs,
impact of a woodland management which are laid singly on leaf litter
programme aimed at reversing the (often dead Bracken), or amongst
decline of Britain’s most threatened moss growing on limestone outcrops.
butterfly the High Brown Fritillary The larvae hatch in early spring and
Argynnis adippe, in its national spend long periods basking on dead
stronghold the Morecambe Bay Bracken where there is little grass
Limestones. cover or in short, sparse vegetation.
The High Brown Fritillary is Temperatures in these microhabitats
Britain’s most threatened butterfly, can be 15–20 °C higher than in
having undergone recent major surrounding grassy vegetation,
16 | Landscape-scale conservation for butterflies and mothsSam Ellis
Sam Ellis
Both coppiced woodland and Bracken mosaics are used by breeding High Brown Fritillaries
allowing the larvae to develop quickly
in otherwise cool spring weather.
The High Brown Fritillary has
been recorded with a presumed
breeding presence (i.e. suitable
breeding habitat present) on 65
Morecambe Bay Limestones (and
South Cumbria Low Fells) sites. In
2007, when a new site dossier was
produced (Ellis and Wainwright,
2008), 50 sites still supported
populations in eight separate
networks (Figure 1); but the butterfly
had become extinct on 15 sites (23%
loss).
On the Morecambe Bay
Limestones the High Brown Fritillary
appears to be threatened more by
changes in habitat quality caused
by succession rather than direct
habitat loss. Many sites are large © Crown Copyright and database rights [2012]. Ordnance Survey 100022021
(median area = 27.7 ha), but
Figure 1 Location and extent of High Brown Fritillary sites in eight networks on the
suitable breeding habitat within
Morecambe Bay Limestones (green ellipses) and South Cumbria Low Fells (brown
them is probably quite localised. ellipses) in 2007
Within networks most sites are
either contiguous or close to one Nearly half the sites are owned or Group which comprises 11 partner
another and isolation is unlikely to leased by conservation organisations organisations. In 2007 nearly
be a significant factor. Nevertheless and on many the conservation of 80% of sites were in some form of
extinctions on smaller, more isolated the High Brown Fritillary is a key management which could benefit the
sites suggests a metapopulation objective. Efforts to conserve the butterfly, although its scale on many
structure and therefore loss of butterfly began as long ago as the was unknown (Ellis and Wainwright,
connectivity may be important for mid-1980s and have continued to 2008).
smaller outlying sites and networks the present day under the auspices By 2007 about half the
(Ellis and Wainwright, 2008). of the High Brown Fritillary Action Morecambe Bay Limestones
Landscape-scale conservation for butterflies and moths | 17400
Project methods
350 In 2008 a four-year programme
Active (n = 11); no significant trend - stable
of coordinated and targeted
300
management commenced to reverse
Population index
Inactive (n = 25); 74% decline (PLand management results a third less than 200 m but a fifth around 5% cover (Figure 4), despite
exceeding 600 m. the fact that the individual features
After the first three years, at least
Ellis and Wainwright (2008) which comprise good habitat quality
114 clearings and rides had been
collated woodland management (violets, exposed rock, Bracken
managed, potentially restoring 60 ha
data from nine key sites for the or leaf litter) occurred at much
habitat on 23 sites (Table 1, Figure
preceding 23 year period (1984- higher frequency or abundance.
3). This is a conservative estimate
2006), when a total of 46.4 ha of Some suitable fritillary habitat was
because not all sites managed
habitat was restored. Whilst no doubt produced in 97% of clearings and
through WIGs were accessible to
an underestimate for the whole rides, but at less than 2% cover
survey. Most management was
landscape, the average of 3.8 ha per in a third of these, and exceeding
undertaken in the core Arnside/
year for the seven year period 2000- 10% cover in only 5%. We believe
Silverdale and Witherslack/
06 supports the notion that there is the significant differences in violets,
Whitbarrow networks, with much
now more woodland management Bracken litter, grass cover and scrub/
of the remainder in the Brigsteer/
ongoing in the Morecambe Bay coppice regrowth size (the latter
Helsington Barrows network (Table
Limestones than for many decades. two negative indicators for suitable
2). Management was funded more
Despite the scale of the current habitat) reflect the greater number of
or less equally between GrantScape
project, management was only scrub clearances undertaken through
and WIGs, with FCE responsible for
implemented on 28% of current or GrantScape. Although the locations
all the conifer clearance undertaken.
former High Brown Fritillary sites. of coppice coupes were selected on
The total cost of the GrantScape
Approximately 6% of the total area of the advice of project officers, based
management was £81k. There were
the project sites has been managed on the presence of features such
significant differences in clearing size
to date, equating to about 7% of the as rocks and/or shallow soil, it is
but this is largely attributable to the
woodland, 5.5% of ancient woodland, less easy to predict the vegetation
conifer clear-fells, with two exceeding
10% of PAWS and 7.5% of the composition following clearance. On
5 ha. Most other clearings were
calcareous grassland resource. the other hand, violets and Bracken
relatively small, with coppice coupes
Both GrantScape and WIG litter are more likely to be still present
half the size of scrub clearances.
clearings and rides produced equally under scrub patches, key factors in
There was also considerable
good fritillary habitat, on average their selection for clearance.
variation in ride length with about
Area (ha) managed under different funding sources
Commission
GrantScape
or ride (ha)
of clearing
Landowner
Mean area
clearings
England
England
or rides
Forestry
Natural
Private
No. of
WIGs
Total
Coppicing 56 0.24 5.50 7.58 0 0.27 0 13.35
Scrub management 25 0.58 7.27 7.15 0 0 0 14.42
Ride management 25 0.59 8.24 5.92 0 0 0.49 14.65
Ride management length (m) 25 402 4,570 4,930 0 0 540 10,040
Conifer clear-fell 8 2.20 0 0 17.61 0 0 17.61
Total 114 21.01 20.65 17.61 0.27 0.49 60.03
Table 1 Management classified by management type and funding source implemented on High Brown Fritillary sites on the Morecambe
Bay Limestones 2008-11
100 3
(unless otherwise stated)
90
Grantscape Grantscape
80
WIG WIG
70 **
2
60
*
50
40 **
Percentage
30 1
20
**
10
0 0
Suitable
fritillary habitat
cover
Violet
frequency
Rock/shallow
soils cover
Bracken litter
frequency
Leaf litter
frequency
Grass cover
Regenerating
scrub cover
Brash cover
Standards
density (no/ha)
Regeneration
height class
Deer impact
class
Figure 4 Mean habitat condition responses under the GrantScape (53 clearings/rides) and WIG (49 clearings/rides) funding
programmes in 23 Morecambe Bay Limestones sites in 2011(significant differences indicated by * PSpecies response underestimate of occupancy for
Dave Wainwright
several reasons. Firstly surveys
Prior to the project commencing,
were nearly all undertaken in the wet
the High Brown Fritillary regional
summer of 2011, when the regional
population trend had declined by
population index was at its lowest.
2007 to its lowest index in 18 years
Secondly, the median survey time
monitoring. Thereafter the population
was only eight minutes and the
increased each year until 2011,
butterfly may have been present but
which produced the lowest ever
missed in some clearings and rides.
index. Undoubtedly the wet summer
Thirdly, only confirmed identifications
of 2011 was a key factor, but it is
were recorded, with unidentified
unclear how much of the previous
large fritillaries seen in 37% of the
increase could be attributed to
unoccupied clearings and rides.
improved management, because only
Dave Wainwright
Confusion arises only between the
48% of project sites were monitored
High Brown and Dark Green Fritillary
by transects. In some cases
Argynnis aglaja, but not with the
management was undertaken along
Silver-washed Fritillary Argynnis
transect routes, especially on existing
paphia. The ratio of High Brown
rides, but in other clearings and new
Fritillary to Dark Green Fritillary was
rides they had not been previously
approximately 1: 2.4, suggesting 124
monitored, demonstrating the need
of the 429 unidentified large fritillaries
for targeted survey by timed counts in
could be the former. It is therefore
each clearing and ride.
reasonable to assume the target
The High Brown Fritillary was
species was present in some of the
recorded from 23% of the monitored
apparently unoccupied clearings/
clearings and rides (Figure 5, Table
Impact of management on a shady ride at rides.
Halecat Woods 2). However, it is likely this is an
Network
Witherslack/
Hutton Roof
Whitbarrow
Hampsfield
Helsington
Silverdale
Brigsteer/
Arnside/
Barrows
Total
Fell
No. sites managed 9 1 1 7 5 23
No. clearings/rides 48 1 4 41 20 114
No. occupied sites 2007 7 1 0 5 1 14
No. occupied sites 2011 9 1 0 7 1 18
Change in occupancy 29% 0% 0% 40% 0% 29%
No. extinct sites 2007 1 0 0 1 2 4
No. extinct sites 2011 0 0 0 0 2 2
No. potential sites 2007 1 0 1 1 2 5
No. potential sites 2011 0 0 1 0 2 3
No. occupied clearings/rides 2011 16 0 0 10 0 26
Proportion occupied 2011 34% 0% 0% 25% 0% 23%
No. unoccupied clearings/rides 2011 31 1 4 30 20 86
No. unoccupied clearings/rides with 15 0 2 11 13 41
unidentified large fritillaries 2011
Table 2 Changes in High Brown Fritillary occupancy in response to management in five Morecambe Bay Limestones networks 2008-11
20 | Landscape-scale conservation for butterflies and moths© Crown Copyright and database rights [2012]. Ordnance Survey 100022021
a) Northern end of the Arnside/Silverdale network
© Crown Copyright and database rights [2012]. Ordnance Survey 100022021
b) Southern end of the Witherslack/Whitbarrow network
Figure 5 High Brown Fritillary occupancy in 2011 of clearings and rides established 2008-11 in relation to overall site occupancy in parts
of the two main Morecambe Bay Limestones networks
Landscape-scale conservation for butterflies and moths | 21but also where there is least evidence a management group bringing
Sarah Bradley
of fragmentation and isolation. All together seven landowners to
known sites are now occupied in coordinate management proposed
both networks, bar one small isolated for c.100 ha of land in part of the
site. However, there were no re/ Arnside/Silverdale network. Close
colonisations of the 20 clearings working relationships with several
and rides in the Brigsteer/Helsington large estates and businesses have
Barrows network. Former sites here been established enabling Butterfly
are more isolated than in the two core Conservation to work alongside
networks but were still less than 1 km tourism and rural enterprises (e.g.
from a potential source population, commercial shooting), as well as
and large unidentified fritillaries were contributing to the employment of
recorded in 65% of clearings and many local contractors.
rides.
The project has been beneficial Key lessons
for a number of other UK BAP Priority This project provides evidence of
Species butterflies and moths utilising the rapid response of a threatened
similar habitat. Despite less intensive butterfly to targeted management,
sampling (only 21% of timed counts with colonisation of new habitat
undertaken during their flight period), patches within already occupied
Volunteers managing a ride in
Witherslack Woods
the spring-flying Pearl-bordered sites, as well as of nearby former
Fritillary Boloria euphrosyne was and potential sites. The presence
known to have re/colonised two sites of the butterfly on several rides/
Occupied clearings and rides were
(increasing the regional resource linear scrub clearings, and the site
significantly larger than unoccupied
from 14 to 16 sites), the Duke of re/colonisations suggests the High
ones (Figure 6). Whilst this partly
Burgundy Hamearis lucina colonised Brown Fritillary has also utilised
reflects the butterfly’s colonisation of
one new site and the pyralid moth improvements in connectivity.
some large clear-fells, these data do
Anania funebris re/colonised two However, more isolated sites, do
emphasize the importance of creating
sites. The early summer species, not as yet, seem to have been re/
habitat of sufficient size within a
Northern Brown Argus Aricia colonised, but this may simply reflect
site to maximize the chances of
artaxerxes and Small Pearl-bordered the relatively short timescale and
colonisation. Unsurprisingly occupied
Fritillary Boloria selene were some may well be occupied in the
clearings and rides were also
respectively recorded from 24 and next few years should habitat remain
characterised by more abundant or
28% of clearings/rides. suitable. Occupancy of some of the
frequent fritillary habitat, violets, rock/
shallow soils, Bracken litter and by former/potential sites is particularly
lower standard densities. Brash cover
Building local partnerships important in that once populations
was also significantly greater but this Promoting a sustainable future is become established these may act as
is explained by the occupancy of critical to the project’s success and stepping stones to the more isolated
some clear-fells. central to this is recruitment of new sites in the future. There are also a
An increase in High Brown volunteers who can contribute to large number of potential sites in this
Fritillary occupancy of 29% was both practical management (e.g. landscape many of which are in close
recorded on project sites (Figure 5, coppicing, scrub burning) and proximity to occupied patches and
Table 2). Between 2009 and 2011 the survey and monitoring of both sites and which can now reasonably
the butterfly recolonised two former butterflies and habitats. During the expect to be colonised once
sites, including one where it had first three years over 40 work parties management is implemented.
not been recorded since 1983, and were held, working with both existing We believe the patch occupancy
colonised two with no previous partner organisations and new ones rate of 23% reflects the localised
records. Colonisations were confined such as a local Further Education nature of suitable habitat (around 5%
to the core Arnside/Silverdale and college. on average) for this most demanding
Witherslack/Whitbarrow networks, Several local partnerships of species but is very probably an
where most work was undertaken, have been developed including underestimate and further monitoring
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