Wednesday 4 March 2015

Bat Surveying in the Touraine Loire Valley

When my friend Jean Claude asked me if I wished to go on a bat survey I accepted with alacrity. I like bats and see them often but don't know all that much about them. This was a chance to hang out with professional bat workers.

Chateau de Cingé, winter home to 7 species of bat.
The survey group included three members of the local bat group (including my friend Corinne), someone on a placement with the League pour la Protection des Oiseaux (LPO), me, Jean Claude and his wife Elisabeth. We were joined halfway through by Hélène, who lives at one of the survey sites and Elisabeth had organised a simple but delicious lunch for us.

Daubenton's Bat. 
Virginie's tip for distinguishing this species from its lookalike cousin the Whiskered Bat is that Daubentons have pink noses, Whiskereds have black.
We visited a number of sites, which ranged from the cellars of several chateaux to some holes in the ground. My top tip for anyone who wants to see privately owned chateaux not open to the public -- join a bat survey group! We visited three, one of which caused me to immediately lose interest in bats and spend quite a bit of time photographing architectural details.

Large Mouse-eared Bat.
The bats were photographed by me as quickly as possible without flash but with
Virginie shining her torch on them.
Jean Claude had organised the day and set up meetings and permissions with landowners but the surveying itself was led by the redoutable Virginie, from the local bat group. She is an experienced bat surveyor and was able to spot a bat crammed into the darkest most unfeasibly narrow crevice and identify it to species level at a glance. Just amazing! All species of bat are protected in France, which means you cannot disturb them at roosting sites. The national monitoring programme orchestrated from the Natural History Museum in Bourges. Last year 13 000 individual bats were counted in Indre et Loire.

Holes in the ground ideal for hibernating bats. 
Unusually for this area these former quarries are sandstone, not limestone. Virginie is in the blue hat, Lucie (LPO) next to her. The spaniel belongs to the Chateau de Vinceuil estate manager and was very excited to be bat surveying with her new friends.
Virginie warned us not to disturb the bats as they were hibernating. We had to be quiet, no loud chatting in cellars and caves. We couldn't all go into a cave or cellar at the same time as our body heat would raise the temperature and the hibernating bats would start to wake up. We mustn't shine our torches on sleeping bats for more than a few seconds and of course, no flash photography.

The remains of beetles that have been eaten by a large bat (either Greater Horseshoe or Large Mouse-eared according to Virginie). The discarded wing cases had mostly come from Dor Beetles but there were also some ground beetles and a couple of other families represented.
Most of the bats we saw were tiny, dark brown and extremely difficult to spot in the dim light. They tuck themselves away between stones, in narrow gaps between wooden lintels or hanging from ceilings high up in the dark.

Chateau de Bridoré.
 We saw a total of 35 individuals from 8 species. The plan is to get together again in June for a follow up survey of summer roosts.
Species and numbers seen:
4 Greater Horseshoe Bat (Fr. Grand Rhinolphe) Rhinolophus ferrumequinum.
10 Lesser Horseshoe Bat (Fr. Petit Rhinolphe) R. hipposideros.
5 Daubenton's Bat (Fr. Murin de Daubenton) Myotis daubentonii.
7 Whiskered Bat (Fr. Murin à moustaches) M. mystacinus.
2 Natterer's Bat (Fr. Murin de Natterer) M. nattereri.
2 Large Mouse-eared Bat (Fr. Grand Murin) M. myotis.
1 Barbastelle (Fr. Barbastelle) Barbastella barbastella.
4 Pipistrelle (Fr. Pipistrelle) Pipistrellus sp.

5 comments:

Tim said...

You did have fun....
roofers almost finished....
no bats or bat traces in longère...

Probably all in the walls of the barn, where I've seen them using the same holes as the birds in summer.
As the birds roost in the same holes in winter, the bats must get extra warmth from their co-habitees!

Tim said...

And the tower in the first picture is real Rumplestiltskin stuff....
you can see the long hair dangling down from that window!

Sheila said...

Great photos, Susan, I don't think the bats of.
Texas hibernate. We must have enough year-round
bugs to keep them fed.

Susan said...

Many thanks for the loan of a headtorch. I must remember to return it ...

Susan said...

I don't know if your lot hibernate. All I know about NA bats is that they are being threatened by white-nose fungus, which came from Europe and they have no immunity to.

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