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Thursday, 8 September 2011

A Weekend With Engelbat

I once worked on a bat project with someone whose sense of humour was completely absent. Anyone who knows me will tell you that my sense of humour is ever-present and decidedly peculiar, so things would always be a little difficult! This person was adamant that individual bats should never be given names as it anthropomorphises them, though in my view giving something a name simply labels it and is harmless (it is poor interpretation of behaviour that anthropomorphises a wild animal). The result of this difference of opinion is that, in honour of the humourless one, any bat which passes through my hands is immediately given a ludicrous name. This is how Engelbat (Engelbat Humperdink? Geddit? No? See what I mean?) came to be named.

He was a juvenile Brown Long-eared Bat (Plecotus auritus), found one July morning on the ground floor of a large country house. The house has a known BLE maternity roost in the attic, four stories above, but Engelbat had wandered quite some distance from there and looked rather sorry for himself, covered in cobwebs and tucked under a radiator.

I had no way of knowing why he had left the roost. This site has no history of bats straying into the building. It's possible his mother had died, causing him to become dehydrated and leave the roost in search of water. However, as he was old enough to fly it is perhaps more likely that he got separated from his mother and simply ended up in the wrong place. I often explain to roost owners that young bats are just as likely to do something silly as young humans.

A close-up of Engelbat's wing, showing the clear patches (unossified bone) in his joints which indicate a juvenile.

I don't normally get involved in bat rehabilitation work. It's a difficult, skilled and phenomenally time-consuming job, so I normally pass casualty bats on to those dedicated individuals who excel in it (hats off to Tracey, Carol and Nigel!). However, Engelbat was a bit different in that he was several weeks old and capable of flight. he just needed some TLC and a plan to get him back into the company of his mother.

Having given him a drink of water (always the number one priority with a casualty bat - they can go a few days without food, but dehydration is a swift killer) I checked Engelbat over for signs of injury and found none. I then took him home and installed him in the bat-cage. This is simply a small plastic cage of the type used to transport hamsters etc. Inside is a shallow water-bowl, a glass jar of warm water with a towel wrapped round it (to simulate his mother) and a canvas pouch hanging on one site, to allow him to retreat out of site into a simulated crevice. He quickly grabbed onto the warm sock and settled down and I left him to get used to his new surroundings. Later he left the sock and took a drink from the bowl, before moving up into the canvas pouch: all positive signs.

Engelbat with the warm sock which acted as a mother/colony substitute.

A while later Isla and I got him out of the cage to feed and assess him. He had done a couple of droppings in the cage, indicating that his digestive system was functioning. When offered a mealworm he grabbed it with enthusiasm, but had some difficulty chewing it, a bit like a small child given a hard toffee. Mealworms are the standard food source for casualty bats, but for younger animals their tough outer skins are a bit too chewy. We tried him on "white" mealworms, i.e. those which have recently shed their skins and have not properly hardened. He found these easier, but still struggled, so from then on we fed him mostly mealworm innards. This is a delightful meal to prepare. First slice the head off a mealworm, then squeeze out its insides as though its a tube of toothpaste. The resulting blobs of vile gunk were voraciously devoured. He prove to be a slightly aggressive little bat, using his forearms to "stamp" at anyone who came too close. Male Brown Long-eareds have a reputation for being grumpy when handled and he fitted that stereotype quite well!

A brief video of Engelbat slowly munching his way through a white mealworm.
So far he ticked a lot of the boxes for being capable of rapid release: no injuries, functioning digestive system, eating and drinking well, so the final test was could he fly? He quickly demonstrated he could by flying happily round and round the living room. Brown Long-eareds are slow-flying bats, so the restricted space didn't seem to faze him at all and eventually he astonished us by managing to land and somehow grip a smooth painted wall, which I'd never seen a bat do before. Several more flights were managed with aplomb.

As he was clearly a competent flier for his age that led us towards how to restore him to his colony. Placing stray infants back into roosts is a questionable approach, as it is impossible to know whether the animals mother is still within the colony, or whether the juveniles wandering may be due to her death, for example killed by a predator. If this were the case then returning the juvenile to the roost may not be the best way forward.

After a conversation with Tracey Joliffe (a very experienced bat carer) for a second opinion, we took Engelbat back to the roost at sunset and placed him on a wooden bench which the adults fly over on their way to their feeding grounds. Our expectation was that his mother would encounter him and encourage him to fly with her. As it happened he chose to fly on his own and flew very competently along the flight line used by the colony, into the nearby woodland.

Of course it's impossible to tell the outcome of a casualty bat returned to the wild (unless you are Maggie Brown, who has done some amazing work tracking her casualties post-release, to evaluate their success). Hopefully he fed successfully and returned to the roost with the rest of the colony and hopefully he teamed up with his mother, if she was still alive. We'll never know for certain. Now I have to think up another ridiculous bat name, ready for the next bat who comes to stay...

If you're interested in caring for sick, injured or orphaned bats the best starting point is to speak to an existing bat carer, who can mentor you and help you get going. It's easy to get things wrong and sound advice and support is essential if you want to get it right. Contact your local bat group to find out who does bat care in your area. You can find your local group via the BCT website (and if you're not already a member...join!) . Another great source of information is the "Bat Rescue Manual", published by the West Yorkshire Bat Hospital, who also publish a regular newsletter: "Bat Care News". Your local bat carer will be able to put you in touch.

BCT Website: BCT Bat Groups page

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