bats of bunessan

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Bats of Bunessan Daniel Howie Volunteer Seasonal Ranger Mull and Iona Ranger Service National Trust for Scotland

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Page 1: Bats of Bunessan

Bats of BunessanDaniel HowieVolunteer Seasonal Ranger Mull and Iona Ranger Service National Trust for Scotland

Page 2: Bats of Bunessan

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Contents

1. Introduction2. Background3. Ecology4. Distribution 5. Bats of Bunessan6. Species7. Tonight’s plan

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Introduction

• Daniel Howie – Volunteer Countryside Ranger – 10 week placement

• Graduate from SRUC and University of Edinburgh– Degree in Environmental Protection BSc Hons

• Dissertation focused on bats in West Lothian – Effect of weather variables on bat hibernation

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Background

• Belong to the Order Chiroptera– 2nd Largest mammalian Order– Two sub-orders

• Megachiroptera• Microchiroptera

• Only true flying mammal– Patagiums– Differ from other flying species

• Vampire bats?!

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Ecology

• Habitat – Optimal habitats now rare

• Mosaic of woodland, water and grassland• Wet woodland edges favoured

– Roosts • Hollow trees, rock crevices, caves and infrastructure • Maternal, mating, transitory and hibernaculum

• Echolocation– Highly sophisticated sonar system– Different frequencies e.g. Noctule and natterer’s

• Hibernation – During winter months– Torpor

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A threatened species?

• Suffered severe declines in the late 1970s – Intensification of agriculture

• Amalgamation of fields• Livestock moved indoors

– Increasing urbanization – Remedial timber treatment – Lack of scientific research

• Now a European Protected Species – Illegal to kill, injure or disturb bats and their roosts

• Does it work?

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Distribution in the UK

• Bats in Britain at the western edge of their range– 17 or 18 species

• 9 species in Scotland – Common and soprano pipistrelles – Daubenton’s– Brown long-eared– Natterer’s – Noctule – Leisler’s– Brandt’s– Whiskered bat

• Distribution increases further south and west– Longer winters and shorter summers in the North

• NTS Properties – Culzean Castle and Threave

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Bats of Bunessan

• What can we expect? – Common and soprano pipistrelles – Daubenton’s – Possibly brown long-eared and natterer’s

• Previous bat walks:– Pipistrelles and daubenton’s

• Pipistrelles roosting in Tiroran Eagle Hide – Previously roosts in Bunessan main street

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BCT Survey – 1997 & 2001

• Bat Conservation Trust carried out Ross of Mull Bat Survey– Established there was a ‘Bunessan Colony’ – ‘The Flats’ and old grocery store were two main roosting sites

• Approximately 240 individuals surveyed on each occasion – Pipistrelles

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BCT Survey Map

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Pipistrelles: Common and Soprano

• Sympatric species – Morphologically similar but echolocate at different frequencies– 500-750,000 individuals in Scotland– Feed on midges!!!

• Common Pipistrelle – Echolocates at 45 kHz – More of a generalist when foraging

• Soprano pipistrelle– Echolocates at 55 kHz– Prefers riparian habitats

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Daubenton’s Bat

• Strongly associated with smooth, slow flowing water– Often river glades or lochs – Observed over Loch na Laitch previously

• Rare in north-west Scotland– Are they present on Mull?

• Around 40,000 individuals

• Echolocate at ~48 kHz

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Brown long-eared bat

• Second most abundant species in Scotland

• Found as far north as Sutherland– Absent from outer lying islands

• Unsure if present on Mull

• Predominantly woodland species – Gleaning species – Moths, beetles, flies and spiders

• Echolocates at ~35 kHz

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Natterer’s bat

• Generally a scarce and poorly known species

• Range in Scotland to Great Glen fault – Found on Islay, Skye and Arran– Concentrated populations in central Scotland

• Echolocates at around 50 kHz– Forages mostly on midges!

• 17,500 species in Scotland

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Tonight’s plan