Lepidoptera on Forestry Commission Land in England; Conservation Strategy 2007 - 2017 Review 2012/13
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Lepidoptera on Forestry Commission Land in England; Conservation Strategy 2007 – 2017 Review 2012/13
Lepidoptera on Forestry Commission Land in England
Conservation Strategy 2007 – 2017
Review 2012/13
This Conservation Strategy is an agreement between Forestry Commission
England and Butterfly Conservation. Forestry Commission England agree to
manage their landholding to encourage and support Lepidoptera and in turn
Butterfly Conservation will monitor species populations and provide
encouragement, management advice and support as required.
Both organisations will strive towards achieving favourable conservation status for
the butterflies and moths identified in this strategy across the priority woodlands.
Signed by:
Simon Hodgson, Chief Executive,
Forestry Commission England
Martin Warren, Chief Executive,
Butterfly Conservation
Contents
Foreword .................................................................................................................. 4
Summary ............................................................................................................ 5
1.0 Introduction ................................................................................................... 7
1.1 Purpose of the Report ................................................................................. 7
2.0 Aims of the Conservation Strategy ................................................................ 8
2.1 Overall Aim ................................................................................................... 8
2.2 Specific Objectives ....................................................................................... 8
3.0 Changes to the Conservation Strategy since 2007 ..................................... 10
3.1 Forestry Commission Changes since 2007 ................................................ 10
3.2 Priority Species Designations ...................................................................... 11
3.3 Butterfly Conservation Landscape Projects ................................................. 16
3.4 Strategy Sites and Priority Site Grade changes .......................................... 16
4.0 Conservation Strategy Context.................................................................... 17
4.1 Importance of woodlands for Lepidoptera .................................................. 17
4.2 Changing status of Butterflies & Moths in woodlands and on the FC estate
17
4.3 Forestry Commission management for Butterflies & Moths to date ............ 19
4.4 Current information on the status of Butterflies and Moths on FC land ..... 20
5.0 Prioritising and Grading Priority Sites .......................................................... 21
5.1 Methodology ............................................................................................ 21
5.2 Distribution of sites by grading ................................................................... 22
5.3 Results of Strategy Review 2012................................................................. 23
5.4 Summary Statistics 2012/13 ....................................................................... 27
6.0 References .................................................................................................. 29
7.0 Useful reading ............................................................................................. 30
Acknowledgements ................................................................................................ 31
Appendix 1: Species Grading ................................................................................. 32
Appendix 2. Lepidoptera found on Forestry Commission Land, their conservation
status and requirements......................................................................................... 35
Appendix 3. National Summary of Forest District Priority Sites by Designation ..... 40
Appendix 4: Key policies & strategies affecting Forestry and Biodiversity post-2010
............................................................................................................................... 41
Appendix 5i. Priority Forestry Commission Lepidoptera sites in England by FC
District 2012 ........................................................................................................... 42
Appendix 5ii. Priority Forestry Commission Lepidoptera sites in England by FC
District 2012 associated maps and tables .............................................................. 49
Central Forest District ............................................................................................ 51
East Forest District ................................................................................................. 54
North District .......................................................................................................... 58
South District .......................................................................................................... 62
Ampfield Wood ....................................................................................................... 62
West District ........................................................................................................... 68
Yorkshire District .................................................................................................... 74
Westonbirt Arboretum ............................................................................................ 78
Foreword Butterflies and moths are known to be valuable indicators of the changes affecting the wider countryside and recent studies suggest that a large number of species are in rapid decline. Butterflies and moths are one of the most threatened wildlife groups that inhabit the Forestry Commission Estate and as active land managers; we are able to play an important role in their future. The Priority Lepidoptera Sites identified in this strategy cover approximately 2000 – 8000ha of woodland and associated open habitats such as heathland and limestone pavement. These sites represent approximately 3% of the total Forestry Commission England landholding and 56% of them have SSSI designation. They support populations of some of the UK’s most endangered woodland butterflies and moths including the Pearl-bordered Fritillary and Wood White, as well as the Argent & Sable. The reasons behind the decline of these Biodiversity Action Plan Priority Species are complex; however a lack of woodland management is often cited as an important cause and one that we can act on to support the conservation of these species. Managing woodlands for Lepidoptera will make an important contribution to many other work programmes taking place across the Forestry Commission England Estate including work to enhance the condition of SSSI, Ancient Woodland restoration and Biodiversity Action Plan habitat restoration. With the potential demand for small diameter hardwoods on the increase through developments in the wood fuel industry, new opportunities for the sustainable management of key Lepidoptera habitats are being created. Many Lepidoptera depend on a network of early succession habitats, such as young coppice as well as open, sunny rides for their long-term survival. If we are to prevent the loss of key woodland Lepidoptera from Forestry Commission woodlands, we need to target woodland management practices more directly and more urgently at the Priority Sites listed in this Conservation Strategy. Much good work has already been achieved by Forestry Commission staff working closely with Butterfly Conservation colleagues. A key objective of this strategy is to further raise awareness of the important sites, to ensure that they feature as priorities in both the Design Planning process and the daily management of our woodlands. It also provides the opportunity to underpin a bid for funding to give the Forestry Commission the best chance of achieving the aims of the Strategy by 2017. It is vital that the Forestry Commission’s delivery of Priority Site conservation and management is viewed as part of a much wider programme of delivery to ensure that these diverse and beautiful insects are allowed to increase and thrive in our English woodlands. Simon Hodgson Chief Executive Forestry Commission England
Summary
This strategy supports the agreement between Forestry Commission England (FC)
and Butterfly Conservation to conserve and increase populations of butterflies and
moths by increasing the level and urgency of woodland management across sites
considered to be important for Lepidoptera.
It is aimed at the foresters, conservation managers and planners in each Forest
District who are responsible for planning and implementing the management
activities across our landholding. It provides details of each priority site as well as
more generic information on the habitat requirements of each of our most
threatened species.
With advice and input from Forest District staff and Butterfly Conservation 140 sites
known to be important for butterfly and moth species were identified and formed
the basis of the strategy in 2007. Since the writing of the Strategy in 2007 the
twelve former FC Districts have been condensed to 7 (see Section 3.1). The total
number of woodlands that this review is based on has now changed to 136 as four
sites originally included were disposed by the Forestry Commission in 2012.
Priority Site grading has changed for 11 sites due to colonisations and extinctions
of priority species; an additional 24 sites have either increased or decreased in
‘Total Species Score’ (see Section 3.4 & 5.3). These changes are due to additional
survey effort and knowledge of a species occurrence on a site specific basis. The
following summarises the site changes:
85 (change from 77) sites have been graded A because they support species
such as the Pearl-bordered Fritillary and Argent & Sable that depend
specifically on woodland and require urgent targeted management.
27 (change from 33) sites are graded B. These sites support a lesser variety of
priority species or species that are not so reliant on urgent woodland
management such as the Grizzled Skipper.
24 (change from 30) sites are graded C. These sites support more generalist
priority or species of conservation concern such as the White Admiral.
The Strategy ‘Site Grading’ and ‘Species Scores’ are based on a total of 59
Lepidoptera species of which 38 are currently designated as both Section 41 and
UKBAP Priority Species; 16 butterflies and 22 moths.
33% of sites in the Strategy (45 out of the 136) are or have been part of a Butterfly
Conservation led Landscape project since 2007.
The objectives are to conserve populations of all priority Lepidoptera species on
FC land through active woodland management. This can only be achieved through
raising awareness of the urgency and necessity of each management activity on
the ground. This strategy aims to do that through promoting a better
understanding of the sites important for Lepidoptera and the species requirements
across FC England.
It should become a key document used to inform all stages of the management process from Forest Design Planning through to operational planning and management activity in the woods. The Conservation Strategy will be reviewed with each Forest District on a rolling programme to ensure that it is kept alive and relevant throughout its duration. The overall success will be determined by the status of priority Lepidoptera at priority sites at the mid-term review date of 2012 and again in 2017. In 2012 the information within this Strategy has been reviewed. In 2017 a review of this Strategy and your knowledge of these sites will help us to re-assess Priority Site information and demonstrate conservation success.
1.0 Introduction 1.1 Purpose of the Report None of the work needed to maintain priority Lepidoptera is new to the Forestry Commission – most Priority Sites simply need more action, and urgently. A significant proportion of Priority Sites are Ancient Semi-natural Woodland Sites (ASNW) or Plantation on Ancient Woodland Sites (PAWS), already managed for their biodiversity value or under a programme of restoration back to semi-natural woodland composition. In addition, a number of sites are designated as Sites of Special Scientific Interest (SSSI), many for their butterfly and moth interest and are currently being targeted under PSA agreement to ensure that 95% of the SSSI network on the public forest estate is maintained in favourable or recovering condition, while over time increasing the area of SSSI in favourable condition. To put the conservation of Lepidoptera in context, approximately 3% of the FC estate has been identified as a priority site. These sites form an integral part of sustainable woodland management and should be maintained with the same set of planning and operational tools that are used across the whole estate. Taking an integrated approach means that these sites are managed alongside the wider estate, supporting and contributing to other objectives such as Ancient Woodland restoration, SSSI management and Habitat Action Plan targets. The Forestry Commission is currently facing many challenges. Woodland management for conservation depends on the availability of suitable markets for small diameter hardwoods such as coppice. The most important market for such products, the St. Regis paper mill closed in early 2006. Other challenges include the increasingly wide range of objectives that have to be reconciled whilst competing for the available resources. Securing additional resources will greatly reduce the challenge of improving woodland habitats for Lepidoptera. Although they can be managed alongside other objectives, woodland Lepidoptera are dependent on regular habitat management for their survival. If forest management does not provide, for example, open habitat on a rotational basis, or rides become too shaded or connectivity between areas of suitable habitat is lost, populations can quickly become extinct. It is crucial that Priority Sites, known to be valuable due to their important Lepidoptera assemblages, feature highly in both the Forest Design Plans and the Operational Site Assessments that take place before operations commence, so that opportunities to enhance their habitats are not missed. This strategy aims to reduce the chances of local extinction happening by raising awareness of these sites, of the Lepidoptera they support and of the general habitat requirements of each of the species across the FC Estate. It does not aim to provide detailed, site specific management prescriptions for each Priority Site, but encourages you to seek guidance from Butterfly Conservation staff if required. Priority Site species information contained within this strategy was correct at the time of writing in 2007. It was collated using Butterfly Conservation monitoring data and information from the Forest District staff. This is a working document - use
the Forest District tables to record new sightings or management activities that may
have benefited Lepidoptera. In 2017 a review of this Strategy and your knowledge
of these sites will help us to re-assess Priority Site information and demonstrate
conservation success.
In 2012 the information within this Strategy has been reviewed using national
butterfly and moth data, District Ecologist and Butterfly Conservation
Regional staff comments.
The publication of this strategy in 2007 coincided with the recent National Review
of Biodiversity Action Plan (BAP) Priority Species by the Joint Nature Conservation
Committee (JNCC). A significant number of butterfly and moth species have been
added to the priority list, due to their increasing rarity within the British countryside.
Many of these species occur on Forestry Commission land, again emphasising the
ongoing commitment needed to ensure the objectives of this Conservation
Strategy are achieved.
2.0 Aims of the Conservation Strategy
2.1 Overall Aim
Through active forest management planned for butterflies and moths, FC aims
to conserve populations of all BAP Lepidoptera species on the Forestry
Commission England Estate.
The priorities are to:
Prevent further extinctions
Stabilise colonies and numbers
Increase populations and range of the BAP Priority Species that require
targeted woodland management
2.2 Specific Objectives
This Conservation Strategy will achieve the overall aim above through:
Ensuring that more urgent action is carried out within the Priority Sites that are
listed in this Strategy and that this management is integrated with other
management activities such as PAWS restoration, timber harvesting (including
wood-fuel initiatives), SSSI condition enhancement and Habitat Action Plan
restoration targets.
Raising awareness and promoting a better understanding of Priority Sites and
species to inform and guide all stages of Priority Site management from Forest
Design Planning through to Operational Site Assessment and activity in the
woods.
Increasing communication between FC staff and Butterfly Conservation staff
and to ensure that expert advice is sought by both parties when appropriate.
Encouraging further survey effort for Lepidoptera within FC woodlands,
especially Grade A Priority Sites, and ensuring that records of scarce and
threatened species are forwarded to Butterfly Conservation.
Ensuring increased monitoring of Priority Sites results in more informed and
responsive actions being taken in terms of planning and management activity.
Achievement of the above objectives will be subject to available resources, and
it will be vital to use this Conservation Strategy to underpin and secure
additional funding from other parties to achieve the aims and objectives of this
strategy.
2.3 Further objectives (subject to additional funding)
FC will co-operate with partners over planned re-introductions, using Butterfly
Conservation guidelines. It will be the responsibility of partners to assess
feasibility and conduct actual re-introductions. FC will work with partners to
create and maintain the desired habitat conditions.
In co-operation with partners Butterfly Conservation will identify the key
outstanding research issues for the conservation of Woodland Lepidoptera and
will discuss with research providers.
Butterfly Conservation will produce, in co-operation with partners, an advisory
leaflet to provide the best current information on woodland management for
Lepidoptera.
The success of this strategy will be determined by how fully the
objectives of this Conservation Strategy have been implemented and met.
This will be assessed by the number of sites in 2017 maintaining or
improving their populations of Priority Lepidoptera and favourable habitat
condition status.3.0 Changes to the Conservation Strategy since 2007 3.1 Forestry Commission Changes since 2007 Appendix 4 details the key policies & strategies affecting Forestry and Biodiversity post-2010 Forestry Commission Districts Following the 2010 Government Spending Review a restructuring programme was implemented across Forestry Commission England which resulted in the reduction of administrative areas for the public forest estate from 11 to 6 Forest Districts plus the National Arboretum at Westonbirt. Following this reorganisation each Forest District now has an Ecologist responsible for providing a support role to the local forest planning and operational teams and maintaining partnership working with key conservation stakeholders. The District Ecologists are responsible for championing the joint strategy for Lepidoptera on the public forest estate and ensuring that its objectives are delivered via strategic and operational plans. Please refer to Figure 1 which depicts the former and current Forest Districts. Figure 1. Left: Forestry Commission Districts 2007 Right: Forestry Commission Districts 2012 Site Disposals Prior to the Governments formation of the Independent Panel on Forestry and the associated moratorium on site disposals some four priority sites originally listed in the 2007 strategy have been disposed of. These sites are listed in Table 1.
Sites Disposed
Priority Site FC District 2007-
Grade Sites Disposed 2012 Sites Disposed species Asc.
A Rewell Wood South Pearl-bordered Fritillary
White Admiral, White Letter
B Bramfield Wood East Hairstreak
Balls Wood and White Admiral, Silver-washed
C Woodhouse South & East Fritillary
Totals 4
Table 1. Disposed Priority Sites and their Priority Site Grade 2007-2012
3.2 Priority Species Designations
NERC Section 41 species and former UKBAP
Of the 59 species included in this Strategy when it was written, 28 were designated
as UKBAP Priority and 14 were under review. Following the UKBAP review in 2007
there were 38 UKBAP Priority Species included; 16 butterflies and 22 moths.
Following UK and International policy change, the approach to species and habitat
conservation in the UK is now being approached at a country level within the UK
Biodiversity Framework.
Consequently, after this Strategy was published all of the 38 UKBAP Priority
Species included were designated in England as Section 41* species listed in the
Natural Environment and Rural Communities Act 2006. This legislation requires
that public bodies, such as the Forestry Commission, have a duty under section 40
of the same act to “have regard” to the conservation of biodiversity in England
when carrying out their normal functions. Since the publication of the NERC Act
(2006) the Lepidoptera Strategy is of even greater strategic importance.
Biodiversity 2020 NERC Section 41 species Action targets
The Biodiversity 2020 Terrestrial Biodiversity Group was requested to highlight the
actions required to assist in the recovery of all species designated as S41. The
group, consisting of a range of expert species ecologists, identified and prioritised
a set of actions for each species.
The actions are considered to be those required for S41 species to recover as well
as meet Outcome 3 of the Biodiversity 2020 strategy written by the government.
The actions were updated in January 2014 and Table 2 has been adapted to
reflect the species included in the Lepidoptera Strategy. The full table can be
downloaded from
http://publications.naturalengland.org.uk/publication/4958719460769792.
All of the actions listed require the ‘Land and Woodland Management’ as
their delivery mechanism.
The definitions of ‘Priority Group’ are as follows:
1 = global concern
2= European concern
3=national concern
4=other national concern*The definition of this designation is as follows “Species of principal importance for the purpose of conserving
biodiversity” covered under section 41 (England) of the NERC Act (2006) and therefore need to be taken into
consideration by a public body when performing any of its functions with a view to conserving biodiversity.
Section 41 and UKBAP Priority Species that require urgent targeted management:
Priority
FC Group (as
Taxon name (=
Common name Species Action text Action priority defined by
synonym)
Score Natural
England)
EWGS designed to
Rheumaptera
Argent and Sable 15 encourage open woodland Medium 3
hastata
with abundant birch re-growth.
Agri-env schemes designed to
preserve its specialised early-
successional habitat. Its
Basil-thyme
Coleophora tricolor 15 specific requirements are not Medium 3
Case-bearer
fully understood & BC should
be consulted for detailed
advice.
EWGS to maintain the open
glades and clearings in
Betony Case- Coleophora
15 woodlands and encourage Medium 3
bearer wockeella
growth of the larval food plant
(betony).
EWGS to maintain the open
Drab Looper Minoa murinata 15 areas in ancient woodlands Medium 3
which this species requires.
Secure habitat management
at all sites through HLS where
possible/ practical; this
Duke of Burgundy Hamearis lucina 15 Urgent 3
species is covered under the
Farmland Butterfly Initiative
(FBI).
Secure habitat management
at all sites through EWGS
Heath Fritillary Melitaea athalia 15 Medium 3
where HLS not possible/
practical.
Secure habitat management
at all sites through HLS (FBI)
High Brown where possible/ practical; this
Argynnis adippe 15 Urgent 3
Fritillary species is covered under the
Farmland Butterfly Initiative
(FBI)
EWGS to preserve the open
Lunar Yellow
Noctua orbona 15 woodland glades where this Medium 3
Underwing
species occurs.
Secure habitat management
Pearl-bordered Boloria at all sites through EWGS
15 Urgent 3
Fritillary euphrosyne where HLS not possible/
practical.
EWGS (based on regular
Small Pearl- rotational ride/ glade
Boloria Selene 15 Medium 3
bordered Fritillary maintenance, or a suitable
coppicing regime).
EWGS (based on regular
rotational ride/ glade
Wood White Leptidea sinapis 15 Medium 3
maintenance, or a suitable
coppicing regime).Section 41 and UKBAP Priority Species where woodland is a secondary habitat but active
management necessary:
Priority
Group
FC (as
Common Taxon name Action
Species Action text defined
name (= synonym) priority
Score by
Natural
England)
Agri-env schemes to ensure suitable
management of the hedgerows &
Barberry Pareulype woodland edges where it occurs; in
5 Medium 3
Carpet berberata particular hedgerows should be
trimmed in late autumn, after larvae
have pupated.
Barred EWGS to maintain/ restore wide
Trichopteryx
Tooth- 5 woodland glades and edge habitats Low 3
polycommata
striped where privet can flourish.
Buttoned Hypena
5
Snout* rostralis
Agri-env schemes, tailored to
manage hedgerows and woodland
edges in a sympathetic way for this
Brown Thecla species. Involves re-planting
5 Medium 3
Hairstreak betulae hedgerows (with blackthorn
included) as well as more
appropriate management of existing
hedgerows.
EWGS to maintain woodland glades
Clay Fan- Paracolax
5 and other suitable open areas in Medium 3
Foot tristalis
woodlands.
Species requirements not fully
understood, but long-term rotational
Common Pechipogo coppicing & occasional felling of
5 Medium 3
Fan-foot strigilata mature trees (to provide gaps) helps
& this should be provided through
EWGS.
Agri-env schemes designed to
preserve the damp grasslands and
Dingy Cyclophora
5 heathlands where the required Medium 3
Mocha pendularia
willows grow inn un-shaded
situations.
Dingy Erynnis EWGS (based on regular rotational
5 Low 3
Skipper tages maintenance of wide glades/rides).
EWGS to provide the coppiced
False Cyclophora
5 woodland & clearings/ glades it Medium 4
Mocha porata
requires.
Agri-env schemes to preserve its
Hipparchia
Grayling 5 specialised, early successional Low 3
semele
habitat.
Grizzled Pyrgus EWGS (based on regular rotational
5 Low 3
Skipper malvae maintenance of wide glades/rides).Priority
Group
FC (as
Common Taxon name Action
Species Action text defined
name (= synonym) priority
Score by
Natural
England)
Agri-env schemes suitably tailored
to maintain the specific (wet boggy
Large Coenonympha
5 mire) habitat, with water levels Medium 2
Heath tullia
properly maintained and sites not
overgrazed.
Secure habitat management at all
sites through HLS where possible/
Marsh Euphydryas
5 practical; this species is covered Urgent 3
Fritillary aurinia
under the Farmland Butterfly
Initiative (FBI)
Agri-env schemes to ensure
Narrow- abundant larval food plant & nectar
bordered sources. N.B. often occurs in same
Hemaris tityus 5 Medium 3
Bee Hawk- grasslands as marsh fritillary and
moth prescriptions should accommodate
both spp. where they both occur.
Ensure that grazing of upland
Northern
Aricia limestone grasslands is not too
Brown 5 Medium 3
artaxerxes intensive and thus accommodates
Argus
the needs of this butterfly.
EWGS designed to maintain
suitable numbers of mature trees
Olive Trisateles
5 with damaged branches, producing Medium 3
Crescent emortualis
the preferred larval food plant of
withered leaves.
Little-known species and a better
Scarce
knowledge of its autecology is
Aspen Sciota hostilis 5 Urgent 3
required to fully understand the
Knot-horn
reasons for its decline.
EWGS to maintain suitable
Scarce
woodland habitat with sufficient
Aspen Phyllonorycter
5 aspen; may need autecological Medium 3
Midget sagitella
studies as well as reasons for
Moth
decline may not be fully known.
Silver-
Plebejus Agri-env schemes to preserve its
studded 5 Medium 4
argus early successional habitat.
Blue
Coscinia
Agri-env schemes to maintain/
Speckled cribraria
5 enhance the specific heathland Medium 1
Footman subsp.
habitat which this species requires.
bivittata
Square-
Xestia
spotted 5
rhomboidea
Clay*
Striped Shargacucullia Agri-env schemes to ensure good
5 Medium 3
Lychnis lychnitis supply of larval food plant.
Waved Hydrelia
5
Carpet* sylvataSection 41 and UKBAP Priority Species associated with mature trees:
Priority
Group
Taxon FC (as
Common Action
name (= Species Action text defined
name priority
synonym) Score by
Natural
England)
Dark EWGS designed to preserve suitable
Catocala
Crimson 3 numbers of large, mature oaks in the Medium 1
sponsa
Underwing species range & habitat.
Agri-env schemes designed to
preserve mature & veteran oaks in
Heart Moth Dicycla oo 3 Medium 4
hedgerows, field margins, commons,
woodland edge etc.
Light EWGS designed to preserve suitable
Catocala
Crimson 3 numbers of large, mature oaks in the Medium 1
promissa
Underwing species range & habitat.
Scarce
Moma
Merveille du 3
alpium
Jour*
EWGS (based on regular rotational
White Limenitis
3 ride/ glade maintenance, with mature Low 3
Admiral camilla
woodland retained).
Action centres on maintaining
suitable elm trees, controlling Dutch
White Letter Satyrium w- elm disease where it still occurs and
3 Medium 3
Hairstreak album re-planting with disease-resistant
elms. EWGS, where appropriate, is
one suitable mechanism for this.
EWGS designed to preserve English
White-
Cosmia Elms in woodlands & woodland edge
Spotted 3 Medium 4
diffinis (including protection against Dutch
Pinion
Elm Disease).
Other key species occurring in woodland:
EWGS designed to maintain/
enhance the damp woodland habitat
The Chortodes
1 where it grows (including Medium 4
Concolorous extrema
encouraging growth of larval food
plant).
Table 2. Section 41 species actions3.3 Butterfly Conservation Landscape Projects Butterfly Conservation has been targeting Lepidoptera conservation through working in a number of sites within a network across a distinct landscape for a number of years. This was in response to the results of metapopulation research which highlighted the importance of reducing species isolation through targeting management across a number of connected sites in a landscape (Bourn & Bulman, 2005; Hanski 1998). A recent publication which highlights five woodland case studies at the landscape scale includes a number of Forestry Commission sites across the UK (Ellis et al 2012). The number of FC Strategy sites that are involved with or included in Butterfly Conservation Landscape projects changes on an annual basis as projects end and others begin. Currently 33% of sites included in the Strategy (45 out of the 136) are or have been part of a Butterfly Conservation led landscape project since 2007. 3.4 Strategy Sites and Priority Site Grade changes The total number of woodlands that this 2012 Strategy review is now based on has decreased to 136 from 140 in 2007 as four sites originally included were disposed of by the Forestry Commission in 2012. Priority Site Grading has changed for 11 sites due to colonisations and extinctions of priority species; an additional 24 sites have either increased or decreased their Total Species Score with an average change in score of +/-10 (see Section 5.3). Priority Original Site 2012 Strategy Post Grade Review 2007 Disposals A 85 77 76 B 27 33 32 C 24 30 28 Totals 136 140 136 Table 3. Total number of Priority Sites Grades 2007 and 2012
4.0 Conservation Strategy Context
4.1 Importance of woodlands for Lepidoptera
Woodland is an extremely important habitat for British Lepidoptera. Sixteen
species of butterfly (out of Britain’s 59 resident species) rely on woodland in all
or part of their range or have a large proportion of their population associated
with woodlands (Clark et al 2011).
Nearly two thirds of all British butterflies will use woodland as breeding habitat.
(Fox et al 2011).
There are around 2500 species of moths in Britain. Moths are found in almost
all habitats and occupy a variety of niches but around 580 species of the larger
British moths occur regularly in woodland habitat from open clearings to ancient
woodland (Clark et al 2011).
Open space within woodland provides a refuge for species of open habitats.
The FC Estate includes important non-woodland habitats, including unimproved
grasslands, upland and lowland heath and mires.
4.2 Changing status of Butterflies & Moths in woodlands and on the FC estate
During the 20th Century there has been an increasingly rapid decline in woodland
butterflies with many species disappearing from much of their former range.
Recent data analysis using the UK Butterfly Monitoring Scheme highlights that
specialist species that occur in woodlands (16) have declined by 56% since 1990
(Clarke et al 2011). It suggests that butterflies associated with woodland clearings
have undergone a marked decline of 80% since 1985.
In the recent publication The State of the UK’s Butterflies 2011, the 10 year
indicator trend using UKBMS data from 1999-2009 suggests that all butterflies
occurring in woodland have declined by 51%.. Butterflies associated with active
woodland management such as coppice clearings and ride management continue
to suffer declines including the Duke of Burgundy and Pearl-bordered Fritillary
which have declines in their 10 year population trend by 46% and 42% respectively
(Fox et al. 2011).
Trends of species that are associated with mature woodland like the Speckled
Wood and Silver-washed Fritillary have increased their populations by 42% and
38% respectively. This suggests that woodland conditions have become
increasingly shaded with a dense canopy, conditions under which these shade-
tollerant species can do well.
Moths have also seen a decline. The number of moths caught in Rothamsted light
traps has decreased by 28% over a 40 year period between 1968 to 2007. Since
the last report (Fox et al. 2006) the UKBAP list of moths increased to 81 and an
additional 71 widespread but rapidly declining larger moths were included.
However following the UKBAP review 142 moth species are now listed as Species
of Principal Importance in England under section 41 of the NERC Act 2006 (Fox et
al 2013).Figure 2. Graphs displaying the trends in woodland butterflies from 1990- 2009 Butterflies and moths are a well-studied group and the decline of so many woodland Lepidoptera may indicate a serious, yet less well-documented, threat to other woodland fauna and flora. A paper by Thomas et al. (2004) showed that butterflies have declined by 71% since the 1970s, substantially more than the decline recorded for British birds (54% over 20 years) and plants (28% over 40 years). The overall decline in Lepidoptera has been strongly linked to changing management, structure and composition of woods, e.g. increasing shade, fewer open spaces and loss of plant diversity. Woodland management has altered rapidly, with a change from extensive coppicing in the late 19 th Century in favour of high forest and the widespread introduction of conifers to previously broad-leaved woodland. Many of the woodlands that were not planted with conifers have undergone 100 years of neglect, especially those in private ownership. The darker conditions that accompany maturing conifer plantations are unsuitable for most BAP Priority Lepidoptera. Few woodland butterflies can cope with well- shaded habitat and this has led to a decline in the majority of species that depend on early succession. Only the Speckled Wood, a species that can tolerate shaded conditions more than most other butterflies has increased in abundance. Conifer feeding moths, such as the Spruce Carpet, Pine Beauty and Satin Beauty have
also done well (Fox et al. 2006b) although the Bordered White, another conifer specialist has declined (-33% in 35 years). The impact of increasing deer numbers on ground flora has been identified as a further threat to Lepidoptera. In some circumstances they can prevent wood re- growth (thus affecting ground flora), the quality of coppice re-growth and, occasionally, may directly graze out food plants. The White Admiral has seen a 50% decline in numbers, thought to be due to Honeysuckle being browsed out by deer (Feber et al. 2001). The intensification of agriculture and removal of hedgerow and woodland fragments have left much woodland isolated, reducing the chances of re- colonisation after local extinctions. The remaining woods are important as refuges for grassland as well as woodland species. This increases the need to maintain habitat variability within each individual woodland block, where habitat fragmentation in the surrounding countryside is high. The Forestry Commission was set up in 1919 with the objective of planting enough forest to provide a strategic reserve of timber for future wars or national emergencies. Afforestation by the Forestry Commission took place at an unprecedented scale following the First World War, often with minimal regard for existing habitats such as native woodland. This undoubtedly had a negative impact on our woodland Lepidoptera. However, many PAWS still retain some of the rich flora of their past and have very good potential to support sustainable populations of Priority Lepidoptera species. Over recent years, the widespread implementation of PAWS restoration through the gradual removal of conifer and the use of natural regeneration to create broad- leaved semi-natural woodland has given rise to more species rich woodlands. However the move towards continuous cover forestry may have an adverse impact on Lepidoptera populations reliant on the early successional stages once provided through clearfelling. It is important that plentiful, well-connected open spaces such as rides are available within these woodlands to ensure that adequate habitat is available for Lepidoptera. In addition FC are now taking a landscape-scale approach to habitat re-creation, and restoration projects are resulting in the creation of larger and more sustainable semi-natural habitat mosaics. FC woods are now representing a vital conservation resource for butterflies and moths in England. 4.3 Forestry Commission management for Butterflies & Moths to date FC management for butterflies dates back to the 1970s, with practice evolving over the years. Management has developed from small-scale work in limited reserve areas to whole-wood management which provides greater, and more sustainable, conservation opportunities. Small-scale management, using hand or mechanised hand tools in places like Bernwood proved unable to slow succession sufficiently to provide habitat for key early successional species. Larger-scale management plans developed in the late
1970s and early 1980s at places such as Bernwood and Haugh Wood created large open spaces, in particular ‘box junctions’ which could be managed by machine. At the same time ride management suitable for broad, mechanised application was developed by Forest Research and widely applied. However, these practices did not live up to their initial promise because natural succession to grasses and other coarse vegetation meant that managed edges and glades lacked a bare ground/woodland herb component and became unsuitable for early succession species. Considerable effort has been made to overcome this problem, including the use of forage harvesters to remove cut vegetation and selective herbicide application. This has not produced habitat comparable to coppice or high forest felling, although has resulted in suitable habitat in some situations. Clear fells and windblow particularly of conifer, have provided valuable early succession habitat, for example in South East England, and in the wildlife corridors developed largely by felling middle-aged conifer in Wyre Forest. The long-term suitability of these sites will depend on follow-up management, but initial progress has been made. Butterfly management on a ‘whole wood’ basis is now being developed linked to both SSSI and Forest Design Plans (FDPs). In places like Haugh Wood, Wyre Forest, Whitbarrow, Chiddingfold and Bernwood, management plans have incorporated the needs of key species of Lepidoptera and implemented actions to gain positive outcomes. FDPs and SSSI plans in the future must attempt to act on this landscape-scale to halt the loss of BAP Priority Lepidoptera Species. There is an important role for Butterfly Conservation in promoting work across land ownership boundaries to create and maintain linkages. In February 2006 the St. Regis paper mill closed. This provided by far the most important market for small diameter hardwoods including coppice. Its closure makes the sourcing of new and reliable markets vital if affordable and sustainable management is to be achievable into the future. 4.4 Current information on the status of Butterflies and Moths on FC land The Species Action Plan for Butterflies on Forestry Commission Land was published in 2000. The butterfly species information contained in that plan was updated for the Conservation Strategy and information on moths was included. The list for moths is still not exhaustive; however, further survey effort for moths within FC woodlands is to be encouraged and records of scarce and threatened species should be forwarded to Butterfly Conservation. Following the UKBAP Review and NERC Act S41 designations a review of the actions required was published and the actions involving FC are detailed in this review (Section 3.2).
5.0 Prioritising and Grading Priority Sites
5.1 Methodology
Site Grading
All Priority Sites identified within this strategy review are important and collectively
represent the best sites for Lepidoptera across the Forestry Commission England
estate. In 2007 and for this review in 2012, sites have been graded using the
National Moth Recording Scheme and Butterfly Monitoring Scheme records*, a
further grading review will be required in 2017 to assess that efforts have been
directed at those sites which support the most vulnerable species and which would
have been most affected through lack of management.
Sites have been graded A, B or C depending on:
The status of the species (BAP or Species of Conservation Concern)
The degree to which the individual species depend on suitably managed
woodland habitats for their survival.
The number of species present.
The combined species score for an individual site**
Grade Description Species
Score **
Grade A Grade A sites are the highest priority sites. They support >15
at least one woodland BAP Priority Species that
depends on targeted and specific woodland
management operations such as ride management or
coppicing.
Grade B Grade B sites support more generalist priority or species 6-15
of conservation concern that are not so dependent on
woodland habitats or management to maintain early
successional stages.
Grade C Grade C sites also support more generalist priority orSpecies Grading
Appendix 1 details the NERC Section 41 and former Priority BAP Species and
Species of Conservation Concern recorded throughout the FC England Estate as
well as associated species scores used to Grade sites A, B or C.
Habitat Condition Assessment
The habitat condition score describes how suitable the habitat is for the specific
Lepidoptera present upon the site and how well the site is being managed for these
species. The habitat condition of most sites has not been assessed in this review
and will be recommended for the full review in 2017.
Forest District staff were responsible for providing the assessment in 2007 based
on advice from Butterfly Conservation as to the requirements of the species. The
condition assessments used are as follows:
Habitat Description
Condition
Favourable The site is already in favourable condition and current ongoing
Improving management efforts could only work to improve the site further.
Favourable The site is being managed appropriately for the Lepidoptera
species present.
Unfavourable Through appropriate management the site is beginning or is
Recovering predicted to show a move towards favourable condition,
however it has not yet reached favourable condition.
Unfavourable The site is in unfavourable condition but is neither declining nor
No Change recovering. Further management is required to achieve
unfavourable recovering status.
Unfavourable The site has not been appropriately managed for Lepidoptera
Declining for sometime or has undergone a damaging activity. Recovery
is possible and may occur if suitable management input is
made.
5.2 Distribution of sites by grading
The map and tables in Appendix 5 list the Priority Sites included in this Strategy
that were reviewed in 2012 together with the Grade and habitat condition of the
Site following the results. This information has been mapped on GIS and is
available on request. The data is held by the England Biodiversity Information
Officer to whom any updated information should also be sent.
The list of sites is not exhaustive, if key species are found on FC land that
are not listed here, Forest Districts are encouraged to consult with Butterfly
Conservation over management issues if necessary.5.3 Results of Strategy Review 2012 Site Specific Priority Grading Priority Site Grading has changed for 11 sites due to colonisations and extinctions of priority species; an additional 24 sites have either increased or decreased their Total Species Score with an average change in score of +/-10. Of the 11 Priority Site Grade changes, 10 have been positive with 9 sites now graded as A, where 5 woods were regraded from B to A and 4 from C to A, the remaining positive change was from C to B. Of these 10 sites half are or have been involved in a Butterfly Conservation Landscape project. The sites have been re-graded due to a change in Lepidoptera interest, with 80% of sites been colonised by a single species since 2007 and recorded in 2012 i.e. Dingy Mocha (2) Drab Looper (3), Small Pearl-bordered Fritillary (1) and Pearl-bordered Fritillary (2) (see Table 4.). There have been two sites (20%) with a Priority Site Grade change from B to A which have had more than one additional species recorded since 2007. The site with the biggest ‘Species Score’ change of 116 is Chickerell Woods in the East District were 7 new moth and 6 new butterfly species have been recorded. The other site with a ‘Species Score’ change of 45 is Vernditch in the South District which has had the following additional three species recorded since 2007; Drab Looper, Duke of Burgundy and Pearl-bordered Fritillary. Red Lodge Wood, West District is the only site that has decreased in its grade with a change from B to C due to Brown Hairstreak and White Letter Hairstreak not recorded since 2009 and 2010 respectively. Priority Species Colonisations and extinctions Table 5 details the sites and additional species recorded since 2007 which has increased their ‘Total Species Score’ but not affected the overall Priority Site Grade. 58% of these sites are currently or have been involved in a Butterfly Conservation Landscape project. 70% of the sites with an increase in the ‘Total Species Score’ has been due to a single species colonisation and recorded in 2012. The other 30% of sites have had from two to four additional species recorded in 2012. The site which has had the most new species recorded is the Forest of Dean (Highmeadow) in the West District. The following tables detail the 11 Priority Site Grade changes and the change in the ‘Total Species Score’ on an additional 24 sites of which 17 have increased and 7 decreased but did not result in a grade change (see Section 3 & 5).
Change Species Additional
FC Butterfly Site Site
in Total Not Species
Site Name District Conservation Grade Grade
Species Recorded Recorded
2012 Project Name 2007 2012
Score 2012 Since 2007
White
Chicksands Letter X7 moths, x6
Woods East B A 116 Hairstreak butterflies
Drab Looper,
Pearl-
bordered
South East Fritillary, Duke
Vernditch South Woods B A 45 of Burgundy
Dukes on the
Charlton South Edge B A 15 Drab Looper
South East
Eartham Woods South Woods B A 15 Drab Looper
Pearl-
South East bordered
Houghton Wood South Woods C A 15 Fritillary
Pearl-
Midlands bordered
Ribbesford Wood West Fritillary C A 15 Fritillary
Tidenham Chase
Woods West C A 15 Drab Looper
Small Pearl-
Cann Wood, Plym bordered
Forest West C A 15 Fritillary
Moreton South B A 5 Dingy Mocha
Park & Queen
Copse South C B 5 Dingy Mocha
White
Letter
Hairstreak,
Brown
Red Lodge Wood West B C -8 Hairstreak
Chicksands Pearl-bordered Fritillary, Small Pearl-bordered Fritillary, Wood White, Dingy Skipper,
Woods-Additional Brown Hairstreak, Purple Emperor, Argent & Sable, Common Fan-foot, Clay Fan-foot,
Species= White-line Snout, Waved Carpet, Drab Looper, Coleophora wockeella
Table 4. Priority Site Grade ChangesChange
FC Butterfly Site Site Species Not Additional Species
in Total
Site Name District Conservation Grade Grade Recorded Recorded Since
Species
2012 Project Name 2007 2012 2012 2007
Score
Pearl-bordered
Fritillary, Drab
Herefordshire Looper, Fletchers
Forest of Dean Wood White Pug, Common Fan-
(Highmeadow) West Project A A 36 foot
Small Pearl-
bordered
Saving Devons Fritillary,White
Great Precious Grizzled Admiral,Silver-
Plantation West Pearls A A 19 Skipper washed Fritillary
Somerford Dark Green Duke of Burgundy,
Common West A A 19 Fritillary Marsh Fritillary
Dukes on the Pearl-bordered
Grovely Wood South Edge A A 15 Fritillary
Possible Pearl-
Whiteley bordered Fritillary
Pastures colonisastion or
(formally Botley South East unauthourised
Wood) South Woods A A 15 introduction
Cannock Still being
Chase Central assessed A A 15 Argent and Sable
Stonedown South A A 15 Drab Looper
Herefordshire
Wood White White Letter
Wigmore Rolls West Project A A 15 Hairstreak Drab Looper
Dark Green
Fritillary,
Silver-
washed
Fritillary,
?Dingy
Saving Devons Skipper,
Precious Grizzled Small Pearl-
North Wood West Pearls A A 13 Skipper bordered Fritillary
Herefordshire Barred Tooth-
Wood White Argent and striped, Fletchers
Dymock Woods West Project A A 6 Sable Pug, Wood White
Friston Forest East (part) HLS A A 5 Olive Crsent
Wareham
Forest South A A 5 Dingy Mocha
Forest of Dean Pearl-bordered
(Drybrook Rd Fritillary ,
Station etc) West A A 5 Grayling Dichomeris ustellala
Bedford Square- White Letter
Purlieus Central WREN; BIFFA B B 3 spotted Clay Hairstreak
North York
Moore Dukes
Dalby Forest Yorkshire and Pearls A A
Waverley Wood
& Weston Midlands Grizzled Silver-washed
Wood West Fritillary B B 1 Skipper Fritillary
Schiffermullerina
Shrawley Wood West B B 1 grandis
Table 5. Priority Site Increases in Total Species ScoreAdditional
FC Butterfly Site Site Change Species
Species Not
Site Name District Conservation Grade Grade in Total Recorded
Recorded 2012
2012 Project Name 2007 2012 Species Since
Score 2007
Argent and Sable,
Pearl-bordered
Fritillary, Small Pearl-
Chiddingfold South South East Woods A A -45 bordered Fritillary
Parkhurst Pearl-bordered
Forest South South East Woods A A -15 Fritillary
Blackdown Brown Hairstreak,
Forest West A A -10 Marsh Fritillary
Lydford West A A -5 Grizzled Skipper
Herefordshire Wood
Oversley Wood West White Project A A -2 Grizzled Skipper
Mortimer Herefordshire Wood
Forest West White Project A A -1 Dark Green Fritillary
Conserving the Wood Silver-washed
Purslow Wood West White butterfly A A -1 Fritillary
Table 6. Priority Site Decreases in Total Species Score5.4 Summary Statistics 2012/13
Total number
Grade Grade Grade of sites
Forest assessed as
Total A B C
District “Favourable”
Woods Woods Woods
habitat
condition BAP Priority Species that are principally woodland species and require urgent targeted
2007 management:
Central 21 13 4 4 7
Argent & Sable, Wood White, Small Pearl-bordered Fritillary
East 34 16 10 8 15 Basil Thyme Case-bearer, Lunar Yellow Underwing, Duke of Burgundy, Heath Fritillary,
Pearl-bordered Fritillary, Small Pearl-bordered Fritillary, Wood White
North 12 8 0 4 5 Duke of Burgundy, High brown fritillary, Pearl-bordered Fritillary, Small Pearl-bordered
Fritillary
South 27 15 8 4 15 Argent & Sable, Coleophera wockeella, Drab Looper, Duke of Burgundy, Pearl-
bordered Fritillary, Small Pearl-bordered Fritillary, Wood White
West 34 26 4 4 16 Drab Looper, Duke of Burgundy, Heath Fritillary, Pearl-bordered Fritillary, Small Pearl-
bordered Fritillary, Wood White
Westonbrit 1 0 1 0 0
Yorkshire 7 7 0 0 3
Argent & Sable, Duke of Burgundy, Small Pearl-bordered Fritillary
TOTAL 136 85 27 24 616.0 References Bourn N A D, Bulman C R (2005) Landscape scale conservation, theory into practice. In: Kuhn E, Feldmann R, Thomas J A, Settele J (eds) Studies on the Ecology and Conservation of Butterflies in Europe. Vol 1: General Concepts and Case Studies, pp111-112, Butterfly Conservation, Wareham, Dorset Clarke, S. A., Green, D. G., Bourn, N. A. & Hoare, D. J. 2011 Woodland Management for butterflies and moths: a best practice guide. Butterfly Conservation, Wareham. Defra. 2006. Working with the grain of nature - taking it forward: volume I & II. Full report on progress under the England Biodiversity Strategy 2002 - 2006. Defra, London. 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. Feber, R.E., Brereton, T.M., Warren, M.S. & Oates, M. 2001. The impact of deer on woodland butterflies: the good, the bad and the complex. Forestry. Vol 74. No 3, pg 271 – 276. Fox, R., Asher, J., Brereton, T., Roy, D. & Warren, M.S. 2006a. The State of Butterflies in Britain and Ireland, Pisces Publications, Oxford. Fox, R., Conrad, K.F., Parsons, M.S., Warren, M.S & Woiwod, I.P. 2006b. The State of Britain’s larger moths. Butterfly Conservation and Rothamsted Research, Wareham. Fox, R., Parsons, M. S., Chapman, J. W., Woiwood, I. P., Warren, M. S. & Brooks, D. R. 2013 The State of Britains Larger Moths 2013. Butterfly Conservation and Rothemsted Research, Wareham, Dorset Fox, R., Brereton, T. M., Asher, J., Botham, M, S., Middlebrook, I., Roy, D. B> and Warren, M. S. 2011 The State of the UK’s Butterflies 2011. Butterfly Conservation and the Centre for Ecology & Hydrology, Wareham, Dorset Green, D.G. 2000. The Status of Lepidoptera in the New Forest: A report for the Forestry Commission by Butterfly Conservation. Butterfly Conservation, Wareham. Hanski 1998 Metapopulation Dynamics. Nature. Vol 396. Pg41-49 Liley, D., Brereton, T & Roy, D. 2004. The Current Level of Butterfly Monitoring in UK Woodlands: And potential use of the data as a Biodiversity indicator to Inform Sustainable Forestry. Butterfly Conservation Report to the Forestry Commission. Butterfly Conservation Report S04-35, Wareham. Thomas, J. Telfer, M.G., Roy, D.R., Preston, C.D., Greenwood, J.J.D., Asher, J., Fox, R., Clarke, R.T. & Lawton, J.H. 2004. Comparative Losses of British
Butterflies, Birds and Plants and the Global Extinction Crisis. Science. Vol 303. pp 1879-1881. Appendix 4 only: DEFRA (2011) Biodiversity 2020: A Strategy for England’s Wildlife and Ecosystem Services. DEFRA, London, 2011. DEFRA (2013) Government Forestry and Woodlands Policy Statement – Incorporating the Government’s Response to the Independent Panel on Forestry’s Final Report. DEFRA, January 2013. Forestry Commission (2011) The United Kingdom Forestry Standard – The Governments’ Approach to Sustainable Forestry. Forestry Commission, Edinburgh, 2011. Forestry Commission (2011) Forests and Biodiversity – UK Forestry Standard Guidelines. Forestry Commission, Edinburgh, 2011. HMSO (2011) The Natural Choice: Securing the Value of Nature. DEFRA, 2011. Independent Panel on Forestry (2012) Independent Panel on Forestry – Final Report. Independent Panel on Forestry, July 2012. Lawton, J.H. et al. (2010) Making Space for Nature: a Review of England’s Wildlife Sites and Ecological Networks. Report to DEFRA. September 2010. 7.0 Useful reading Specific species reports for certain areas are also available and can be requested from Butterfly Conservation please see examples from the list below: Asher, J., Warren, M.S., Fox, R., Harding, P., Jeffcoate, G & Jeffcoate, S. 2001. The Millennium Atlas of Butterflies in Britain and Ireland, Oxford University Press, Oxford. Bulman, C. 2007. Woodlands – a vital habitat for butterflies and moths. Quarterly Journal of Forestry. Vol 101. pp 29-39 Defra Factsheets are available for most BAP Priority Lepidoptera species with habitat management recommendations included. These are available from Butterfly Conservation or can be downloaded from the website www.butterfly- conservation.org Ellis, S. 2005. Conservation of the Duke of Burgundy (Hamearis lucina) butterfly on the North York Moors 2005. Butterfly Conservation Report S05-37, Wareham. Ellis, S. 2005. Conservation of the Pearl-Bordered Fritillary (Boloria euphrosyne) butterfly on the North York Moors 2005. Butterfly Conservation Report S05-36, Wareham.
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