ENVS 2102 Species Management of The Barbastelle Bat ( Barbastella barbastellus ) By Joshua Humphries
What is the Barbastelle? • Native UK Bat. • Member of the Order “ Microchiroptera ”. (Waters & Waters, 2009: p.8) • Distinctive features: (Wildscreen, 2013a) (JNCC, 2001)
Previous Status/Distribution Past Distribution: Sparsely recorded around England and Wales. Past Status: Population estimated to be around 5000 individuals. Country Estimated Number of Barbastelles England 4500 Wales 500 Scotland 0 Northern Ireland 0 Total 5000 Created from JNCC (2007).
Current UK Distribution Barbastelle Range and Distribution Woodland Survey 1980-2006 2006-2012 (JNCC, 2007) (Bat Conservation Trust , 2014)
Current UK Status • Overall Status: “Unknown”. (JNCC, 2007: p.8) • Current Population Trend: “Unknown”. (JNCC, 2007: p.8) • Listed as Priority Species under Biodiversity Action Plan . (JNCC, 2001)
Current International Distribution (Hutson et al, 2008)
Life History Traits • Life History Strategies: Hibernation and Torpor. • Hibernation Duration: October to May. • Hibernacula: Caves, trees, houses. (Wildscreen, 2013a)
Life Span and Breeding Strategy • Lifespan: 20-30 years. • Polygynous. • K-Strategists. (Waters & Waters, 2009)
Habitat Requirements • Roosting Habitat: Veteran/Dead trees of Ancient Broadleaved woodland. • Foraging Habitat: Hedgerows and water features e.g. streams. (Greenaway, 2005a) (Hedgelink, 2007)
Feeding Habits • “99%” of prey consists of Lepidoptera (Moths). (Sierro & Arlettaz, 1997: p.1) • Catch prey by Aerial Hawking. • Locate prey using u ltrasonic pulse, at “32kHz”. (Bat Conservation Trust, 2010) (JNCC, 2001)
Predators • No confirmed records. Assumed to be predated by: (Wildscreen, 2013b) • Domestic Cats. • Various bird species. Potential bird predators of bats Hawks and Falcons Corvids Gulls and skuas Owls Adapted from Speakman (1991).
Species Management Methods Methods to manage Roosting Habitat : Method 1: Reinstate Pollarding within woodland. Method 2: Maintain Dead Wood. Method 3: Set aside Unmanaged areas of woodland.
Reinstate Pollarding • Cut the top branches of veteran trees. • Cut on rotation of around “20 years”. (Starr, 2005: p.140) Advantages Disadvantages Prolong trees life span. May kill veteran tree. Creation of cracks and Chance of destroying crevices for barbastelle. barbastelle roosts. (Starr, 2005)
Maintain Dead Wood • Maintain around 70m 3 of dead wood, per hectare of ancient woodland. Observed Roost selection • Preserves suitable Expected Roost selection roosting habitat for barbastelles. Adapted from (Greenaway, 2001).
Set aside unmanaged areas • Set aside 10 trees per hectare of woodland, to be unmanaged. • Trees should be connected by linear features. Advantages Disadvantages Provides roosting Tree may become habitat. top-heavy and fall over. (Forestry Commission, 2005) Reduces disturbance during hibernation.
Species Management Methods Methods to manage Flight Lines and Foraging Habitat : Method 1: Plant trees alongside hedgerows. Method 2: Fill-in gapped hedgerows. Method 3: Erect fencing around Water features.
Plant trees alongside hedgerows • 10m hedgerows may be more obvious as flight paths. • Planting of trees can increase hedgerow width. However : • Observations from a study reveal that hedgerows of (Natural England, 2008) varying widths were used by other bat species.
Fill-in Gapped Hedgerows • Gaps in hedgerows increase risk of bat predation. • Planting up gaps would increase the continuity of flight paths, thus connecting Fragmented roosting and foraging Flight Paths habitats. Continuous Flight Paths Adapted from Greenway (2005b).
Erect Fencing around Water Features • Livestock can remove the Advantages Disadvantages food-source of lepidoptera, Increases food Scrub thus limiting barbastelle abundance of encroachment . barbastelle prey. prey abundance. Provides barbastelle prey with shelter. • Fencing can effectively exclude livestock. (JNCC, 2001).
Habitat Management Methods Methods to manage Ancient Broadleaved Woodland : Method 1: Cull Deer Population. Method 2: Erect Deer Fencing. Method 3: Introduce Rotational Coppicing.
Cull Deer Population Threat: Deer browsing. Management: Around “20%” (Mayle, 1999:p.10) of adult females in a population must be culled, per year. Potential Benefits: • Promotes woodland (Forestry Commission, 2010). regeneration and expansion. • Increase in food abundance of barbastelle prey.
Erect Deer Fencing Management: Erection of fencing. Potential Benefits: Can exclude the predominant number of deer from a woodland. Un-Grazed However: • Can indirectly lead to increased browsing of other woodland. Grazed (Mayle, 1999).
Erect Deer Fencing Species Mesh size Fence (mm) Height (m) Fallow 220 x 200 1.5 200 x 150 1.2 Roe 75 x 75 1.5 Muntjac Adapted from Mayle (1999).
Introduce Rotational Coppicing Threat: Dense tree canopy. Management: Rotationally cut trees, every “two or three years”. (Sutherland, 1995: p.336) Potential Benefits: • Increase woodland regeneration. • Increase in food abundance of barbastelle prey. (Plantlife, 2010).
Habitat Management Methods Methods to manage Hedgerows and Water Features : Method 1: Rotationally Cut Hedgerow. Method 2: Create a Buffer Strip around hedgerows and water features.
Rotationally Cut Hedgerow Threat: Over-cutting of hedgerow. Management: Trim hedgerow every 2 or 3 years, instead of annually. Potential Benefits: • Prolonged hedgerow life-span. • Food for other wildlife. Potential Negatives: • Clash with management of specific BAP species. (Natural England, 2007).
Create a Buffer Strip • Threat: Pesticide spray and fertilizer run-off. Management: Establish a buffer strip of around 6-12m, around hedgerows and water courses. Potential Benefits: • Hedgerow will be maintained. • Provides food for wildlife. • May lead to an increase in lepidoptera, supporting (RSPB, 2007). barbastelles.
Conclusion • The Barbastelle is a very rare and severely threatened species, throughout the UK. • To conserve the species, habitats must be managed sympathetically and specifically, with barbastelle bats in mind. • However, each habitats own specific threats must also be managed, to maintain each habitat at FCS.
Any Questions? (Wildscreen, 2013a)
References • Bat Conservation Trust (2010) Barbastelle Bat:Barbastella barbastellus . [Online] Available from http://www.bats.org.uk/data/files/Species_Info_sheets/barbast elle_11.02.13.PDF [Accessed 12 April 2014]. • Bat Conservation Trust (2013). The National Bat Monitoring Programme . London, Bat Conservation Trust. • Bat Conservation Trust (2012) The state of the UK’s bats: National bat monitoring programme population trends 2012 . London, Bat Conservation Trust. • Bat Conservation Trust (2014). Woodland survey results 2012 . [Online] Available from: http://www.bats.org.uk/pages/woodland_survey_results_2012 .html [Accessed 12 April 2014].
References • Battersby, J. (2005) UK mammals: species status and population trends . Peterborough, JNCC/Tracking mammals partnership. • Barkham J.P. (1992) The effects of management on the ground flora of ancient woodland, Brigsteer Park Wood, Cumbria, England. Biological Conservation , 60 (3), 167-187. • Boughey, K.L., Lake, I.R., Haysom, K.A. & Dolman, P.M. (2011) Improving the biodiversity benefits of hedgerows: how physical characteristics and the proximity of foraging habitat affect the use of linear features by bats. Biological Conservation , 144 (6), 1790 – 1798. • Chamberlain, D., Gough, S., Anderson, G., Macdonald, M., Grice, P. & Vickery, J. (2009) Bird use of cultivated fallow ‘Lapwing plots’ within English agri ‐ environment schemes. Bird Study , 56 (3), 289-297.
References • Forestry Commission (2005) Woodland Management for bats . West Yorkshire, Forestry Commission. • Forestry Commission (2010) Managing ancient and native woodland in England . Bristol, Forestry Commission England. • Greenaway, F. (2005b) Advice for the management of flightlines and foraging habitats of the barbastelle bat Barbastella barbastellus . Peterborough, English Nature. • Greenaway, F. (2008) Mammals of the british isles : handbook. 4 th edition. Southampton, The Mammal Society.
References • Greenaway, F. (2001) The Barbastelle in Britain. British Wildlife . 12 (5), 327-334. • Greenaway, F. (2005a) Woodland management advice for Bechstein’s bat and barbastelle bat . Peterborough, English Nature. • Harris, S. Morris, P. Wray, S. & Yalden, D. (1995) A review of British mammals: population estimates and conservation status of British mammals other than cetaceans . [Online] Available from: http://jncc.defra.gov.uk/pdf/pub03_areviewofbritishmammalsal l.pdf [Accessed 12 April 2014]. • Hedgelink (2007) The hedgerow management cycle & scale (HLNK03) . [Online] Available from: http://www.ptes.org/files/1353_hedgemanagementcycle.pdf [Accessed 14 May 2014].
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