Bechsteins bat: an indicator species for ancient forest and orchards
René Janssen & Daan Dekeukeleire Brussel– 24 march 2012
SEVON
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Project - goals • Ecological knowledge o o o
Maternity colonies Foraging area‟s Swarming sites
• Conservation o o
Gathering information Informing policy makers, land owners, etc
• Monitoring o
Bat boxes
2
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Bechsteins – an introduciton • • • • •
Medium sized 7-13,6 gram Broad wings Big ears Very silent sonar
3
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Social organisation • Colonies form closed societies (Kerth & Van Schaik 2011)
• Sex biased dispersal o
Females are extremely faithful to their colonies
4
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Occupies…
Drawing: Peter Twisk
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Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Tree cavities • Up to 50 roost sites per year • Roost switching behaviour: fission & fusion (Kerth et al. 2011) o o
Small groups in function of thermoregulation Parasites
6
Dietz & Pirr, 2009
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Forest specialist • Until 1000 A.C. the most common bat in archaeological research • Indicator species for „old woodlands‟ (Dietz & Pirr, 2009)
• Requires a lot of hollow trees • Small home-range
7
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Swarming behaviour • Mating • Gene flow (Kerth et al. 2003; 2004) • To explore potential hibernation sites
8
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Hibernation • In underground structures • Banding studies: ♀ up to 25 km; ♂ up to 50 km • Only found in small numbers
9
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Hibernation • Often in objects with collapsed parts • Prefers cracks and crevices • Most often overlooked • Example o
German cellar: 57 ind via automatic monitoring though pictures), 0-3 found during several visual inspections (Kugelschafter 2009)
10
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Observations 2003-2008
References: -Vleermuizenwerkgroep Limburg NP -Plecotus, Natagora -Dietz&Pir, 2009 -http://www.naturschutzinfo rmationen-nrw.de -http://www.naturschutz.rlp. de/index.php?id=3&pid1=30
11
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Observations in Flanders untill 2009 • Forts of Antwerp: o o
1 hibernating record No captures during swarming
• Limburg : o o
Annually 2-9 hibernating records Annually 6-13 caputres in 4 nights
• Brussels o o
Only 2 recent hibernating ind Old summer observation (may 1954) 12
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Survey ‟09/‟10 – Nederlands Limburg Mistnetting
Telemetry (tag 0,34 g)
Plecotus auritus in net
Bechsteins bat with transmitter (picture: Luuk Punt)
13
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
First Dutch colony • Capture at the „Vuursteenmijn‟ in Savels bos (11 aug) and capture in the forest (24 aug) • One of the roost sites: 10m high in an European ash
First year female
Second year female, not reproductively active
14
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Tracking back swarming bats • 3 females tagged; 2 in a mine, 1 followed for 11 km to Rijkhoven, then lost
15
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
17,5 km
16
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
First colony for Flanders • Beech in a private forest (5ha) near Vliermaalroot • Hunted in structurally diverse forest • Capture of a juvenile female bat in 2010 indicated reproduction
370 m
17
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Conclusies ‟09-‟10 • • • •
Regelmatige waarnemingen: populatie? Herkomst zwermende dieren onbekend! Aanwijzen van habitatrichtlijngebieden? Bos gekapt, Bechsteins weg!
18
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Survey 2011 • • • • • •
Model to select forests to survey Field visits Mistnetting Telemetry Locating colonies Tracking back Swarming individuals to summer locations SEVON
19
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Model - 1
10 km
20
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Model - 2
(De Keersmaeker et al. 2001)
10 km
21
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Model - 3
10 km
22
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Field visits • • • • •
Tree layes: oak, beech or ash? Diverse herb layer? Ancient forest plants? Coppice woodland? Ponds?
23
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
15 capture locations in 2011
10 km
24
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Mistnetting in Forests • With white hair nets • Bat lure with “distress-calls” • Transmitter <0,35 gram
25 Foto: Karl Vanginderdeuren
Foto: Johannes Janssen
Foto: Johannes Janssen
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Captures 2011
10 km
26
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Roost sites summer 2011
27
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Goals of swarming research • • • •
Blind control of our model Complete the overview of colonies Migration routes Find new swarming locations
28
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Capture at the mines • • • • •
6 limestone mines, 9 nights 661 captures 10 species 120 Bechsteins (26 females) Koegat: first night: 79 animals; 44% Bech.
29
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Tracking back swarming 2011 • 19 females tagged with low-weight transmitters (0,45 gram < 5 % mass) • 2 gr more weight trough feeding and water • Following with cars • Surveying al forests • Chessna for 100%
30 Foto: Karl Vanginderdeuren
Foto: Wouter Teunissen
Foto: Wouter Teunissen
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Summer 2011
Colony ‟09 Summer ‟11 Capture sites ‟11 Col. Swarm „11
10 km 31
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Swarming 2011
Colony ‟09 Summer ‟11 Capture sites ‟11 Col. Swarm „11
10 km 32
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Migration routes • 19 females tagged • 1 transmitter broke down • 1 animal followed into a mine, not found again • 17 of the 19 relocated • 18 animals (17+2009) crossed the E313 • 5 crossed at the bridge near Rijkhoven (incl. 2009)
• 7 animals flew into a mine • Often hunted during migration
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Tag 20 (KG BVN)
34
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Lacroix2011 Zwerm
Kolonie ‟09 Zomer ‟11 Zwerm ‟11 Kol. Zwerm „11
35
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Koegat2011 Zwerm
Kolonie ‟09 Zomer ‟11 Zwerm ‟11 Kol. Zwerm „11
36
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
From colonies Swarm sites
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Nietelbroeken Zwerm 2011
Kolonie ‟09 Zomer ‟11 Zwerm ‟11 Kol. Zwerm „11
38
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
BelleVue Zuid Zwerm 2011
Kolonie ‟09 Zomer ‟11 Zwerm ‟11 Kol. Zwerm „11
39
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Conclusions • All colonies situated in the same region (Haspengauw) • 9 out of 10 colonies situated in ancient forest (Ferraris) o
Importance for conservation
• Swarming sites visited by members of diffirent colonies • Members of colonies migrate to different swarming sites on the same night • Orchards are important as foraging and colony sites 40
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Many thanks to • • • • • • • • • •
Provincie Vlaams Limburg en de Gemeenten Heers en Riemst voor de financiële bijdrage en hun partnerschap bij het Project in Vlaams Limburg; Het RLH, de Bosgroepen en de JNM voor hun partnerschap bij het Vlaams-Limburgse project; Provincie Nederlands Limburg en Solabio (Interreg) voor de financiële bijdrage in 2009 en 2010; Luc Crevecoeur, Karolien van Diest, Patricia Knaepen, Joke Rymen en Francine Theeuwissen voor de prettige samenwerking in de projectgroep; Het Vleermuisvangsysteem, het ANB, Limburgs Landschap, SBB, LL, NM en verschillende particuliere terreineigenaren voor de benodigde (terrein)ontheffingen; Ghis Palmans voor het beschikbaar stellen van Vlaamse gegevens; Pierrette Nyssen voor het beschikbaar stellen van Waalse gegevens; Desiré Paelinckx van het INBO voor het beschikbaar stellen van de BWK- kaarten en bosleeftijdskaart; Heleentje De Brauwer, Jaap van Schaik, Kamiel Spoelstra en Paul Voskamp voor commentaar; Jan Appermont, Urbain Merken en Tom Verschraegen voor de hulp bij het selecteren van vangstplekken; 41
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Acknowlegements – Field work •
2009: Pieter Blondé, Frans Bosch, Thijs Bosch, Huub Don, A-J Haarsma, Raymond Haselager, Jan Hovenkamp, Tjeerd Kooij, Mies Loogman, Johannes Regelink, Jaap van Schaik, Jannah Schenk, Paul Voskamp en vele anderen die één of meerdere dagen hebben meegeholpen met het veldwerk;
•
Bos 2011: Jan Appermont, Joachim Bertrams, Kris Boers, Mark De Brabander, Christel Bouchet, Pieter Jan D‟hont, Pieter-Jan D‟hondt, David Galens, Johannes Janssen, Iwan Lewylle, Willem Proesmans, Jaap van Schaik, Jannah Schenk, Lydia Vanberghen, Karl Vanginderdeuren, Tom Verschraegen en Paul Voskamp.
•
Zwerm 2011: Jan Appermont, Heleentje De Brauwer, Gaby Bollen, Frans Bosch, Thijs Bosch, Julia van der Burgt, Ludwig Darcis, Pieter-Jan D'Hondt, Teddy Dolstra, Winfried Engels, David Galens, Karl Van Ginderdeuren, A-J Haarsma, Raymond Haselager, Jan Hovenkamp, Ruud Kaal, Sanne Kat, Burkhard Kern, Tjeerd Kooij, Thomas Kölsch, Wendy Kreeftenberg, Sander Lagerveld, Stefan Luyk, Iwan Lewylle, John Mulder, Thijs Molenaar, Ruurd Noordhuis, Ghis Palmans, Douwe van der Ploeg, Rian Pulles, Stef van Rijn, Jaap van Schaik, Jannah Schenk, Chiel Simons, Wouter Teunissen, Marc van der Valk, Emmy Veeman, Johan Willems en Sigrid van Woerkom
•
Foto‟s: Karl Vanginderdeuren, Johannes Janssen, Luuk Punt, Wouter Teunissen. Indien onvermeld: René Janssen 42
…
43
Project
Bechsteins
2009
Forest 2011
Swarming 2011
Conclusion
Observations in Belgium • Wallonia o o
o
Summer colony in the Gaume Often encountered during mist net research in summer Recorded in many hibernation sites (also Montange Saint Pierre)
• Brussels: o o
Only 2 observations during winter Old summer observation (may 1954)
• Flanders 49
