Bats in Hampshire. Nik Knight Chairman and Recorder Hampshire Bat Group

Transcription

1 Bats in Hampshire Nik Knight Chairman and Recorder Hampshire Bat Group

2 What are bats? Mammals Order Chiroptera Over 1300 species worldwide Capable of powered flight Fur External ears Viviparous Milk Daubenton s bat

3 Bats are small Brown Long-eared bat Photo: N Knight

4 Common pipistrelle bat

5 Bats are furry Natterer s bat Photo: N Knight

6 Serotine bat Bats have teeth

7 Bats are social, especially the breeding females

8 Photo: N Knight Bats are vulnerable and have been declining

9 British Bats 17 breeding species? Nocturnal All eat insects All use echolocation Harmless Beneficial as they eat pest insects Good indicators of healthy ecosystems Vulnerable All have declined significantly since WW2 We lack knowledge about them Difficult to study

10 Checklist of British Bats Greater horseshoe Lesser horseshoe Barbastelle Brown long-eared Grey long-eared Serotine Noctule Leisler s Common pipistrelle Soprano pipistrelle Nathusius pipistrelle Daubenton s Natterer s Bechstein s Whiskered Brandt s Alcathoe Greater mouse-eared

11 Pipistrelle bats

12 Common pipistrelle

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14 Photos: N Knight Pipistrelle roost

15 Why do bats have big ears? Brown long-eared bat

16 Bat Sounds Long-eared bats are able to hear insects moving about All our bats make very high pitched sounds Far too high for us to hear Called ultrasound Used for echolocation Also they make social calls Bat detectors make these sounds audible to us

17 Bat detector Reduces the pitch of bat sounds to the range of human hearing Display shows the frequency to which the detector is tuned Output to loudspeaker, headphones and recorder

18 Analysis of pipistrelle echolocation

19 Spectrogram of serotine bat echolocation

20 Bat ultrasound All our bats use echolocation for navigation and locating food Each bat species has a distinctive sound pattern Loud, e.g. noctule Quieter in stealthy bats, e.g. brown long-eared Rapid pulses of sound, e.g. 10 per second Bats listen for the echoes in the gaps between the pulses Needs lots of energy Also they make distinctive social calls

21 Geographical features of importance to bats Watercourses Tree lines Hedges Railways Linear features used by bats for commuting from roosts to foraging areas Open spaces diminishing and under threat in Havant Artificial illumination disrupts insects Bats need sources of insect prey in all seasons

22 What bats do we have in the Havant area? Potentially all the UK species At least 14 species have been recorded Including great rarities, including Bechstein s bat Havant s natural heritage should be celebrated, recorded and protected Much more recording is necessary to get an accurate assessment

23 What bats have been recorded in the Havant area? Consulting the Hampshire Bat Group records Within a 5 km radius of St Faith s Church, Havant 1430 records (as at March 2017) Dating from 1950 to 2017 At least 14 species Brown long-eared, common pipistrelle, soprano pipistrelle, Nathusius pipistrelle, western barbastelle, noctule, Leisler s, serotine, Bechstein s, Daubenton s, Natterer s, Brandt s, whiskered, parti-coloured

24 Biodiversity Action Plans These exist for large and smaller areas Hampshire E.g. serotine bat as a BAP priority species Local, e.g. Havant Bats mentioned very little Just in general ways This Havant BAP is very out of date as regards bat records

25 Havant BAP Key areas for Mammals Bats are mentioned just in some of the places where they happen to have been recorded prior to 2011 Many areas of great importance are not mentioned Under-recording leads to poor conservation

26 Sites of Interest for Nature Conservation 135 sites in Borough of Havant Good number, but Low level of protection No bat data exists for most of them Bats deserve a higher level of protection

27 Threats to bats Mainly of human origin Loss of habitat, including isolation through fragmentation and loss of flight lines Changes in farming practices Decline in insect populations Build-up of insecticides through the food chain Loss of roost sites, e.g. old trees, gaps in houses Building and development Changes in house building practices Artificial lighting Predators e.g. cats, squirrels, woodpeckers, owls

28 Bats and wind turbines Bat mortality at wind farms Affects some bat species, e.g. noctule, more than others Die from collisions and barotrauma Acoustic surveys and collection of carcasses using trained dogs Variables: site, ground clearance of blades, wind speed, season High mortalities in Germany and USA Operational restrictions, e.g. higher cut-in speeds

29 What can we do to help with bat conservation? Enjoy observing bats Recording report to the Hampshire Bat Group Education Vigilance for threats Favourable habitat management Increase bat roosting opportunities Press for higher levels of protection Ensure Biodiversity Action Plan recommendations are carried out

30 Encouraging bats in your garden Encourage insects Native plants Night-scented flowers Trees and shrubs Ponds and bogs No goldfish in ponds to eat insects Compost heaps Log piles Avoid pesticides Keep cats indoors at dusk

31 Are bat boxes useful? Yes Make up for loss of natural roosts Bats may take a long time to use them Boxes are often used by other wildlife Training and special licence are required to check them Inspection is a useful survey technique

32 Bats and the Law Wildlife and Countryside Act 1981 (as amended) Conservation of Habitats and Species Regulations (2010) Source: BCT Website April

33 What does the Hampshire Bat Group do? Promote and support bat conservation in Hampshire Education raise public awareness of bats and the challenges they face Recording bat distribution Research bat conservation is hindered by lack of knowledge Bat care and rehabilitation A Partner Group of the Bat Conservation Trust Amazing technological advances are enabling a Golden Age of bat research Bats are Superheroes of the Night

34 Advice is available

35 Helpline