I am licensed by English Nature to care for bats that would be unable to survive in the wild. One of these is a female Common Pipistrelle, who came to us as a young juvenile earlier this year, after been found on the ground by a member of the public. She seems unable to fly, despite our best efforts to enable her to do so; we wonder whether she has ever flown.
We took her to a bat expert, who advised us that we should keep her in care long-term. She suspected that she has inner ear damage or a history of head injury, although, she has always - while in our care - appeared completely visible-injury free, and is well nourished with a healthy coat. We wondered if her abnormalities were due to birth injuries?
More recently, another bat carer also suggested inner ear abnormalities.
As she is comfortable in the presence of humans, we are able to show her - for example - after giving educational talks about bats. She sits on my hand and looks up at those who come to see her.
At the moment, she is hibernating off and on and not moving a great deal, but when fully awake, she usually moves, quite fast, in a circle on the ground and often stops to look up; movements that are unusual. However, when she chooses to, she is able to move along the floor on all fours, in a straight line, to reach her destination. She is able to climb (she occupies a large mesh vivarium with another female pipistrelle) but usually sits on the floor. She is hibernating on the floor of the vivarium, under a fleece 'curtain'. The bat with whom she lives, climbs much more readily and is hibernating in a more usual position, hanging on the mesh, behind a fleece at the other end. But the bat in question has not taken her example.
We feed her on freshly killed mealworms, and she often 'kicks' them around before eating them. If anything, she drinks more water than other bats who have been / are in our care. The picture attached makes her look a very light colour for a Common Pipistrelle; this could be the photograph, but she is a lighter colour than usual.
I would be really grateful for suggestions about these unusual behaviours and would welcome references to papers that I could read on her abnormalities. I could not find any.
Thank you
May be this paper has some clues.
http://journal.frontiersin.org/article/10.3389/fpsyg.2013.00396/full
I worked with Short-tailed opossums and when they were stressed (like during breeding trials) they would start running in circles... I would then add special nesting material where they could hide and feel more protected and they would rapidly calm down...
Hello Paulo and Naomie,
Thank you very much for your responses. I have looked briefly at, and downloaded the pdf of the paper you recommended, Paulo, and will be reading it in much greater detail shortly.
Thanks, also, to Naomi. A lot of the bats that we have cared for do seem to seek a hiding place, but this little bat will come out of hiding - for example - to eat, and will do her running round in tight circles on the piece of paper towel on which her food is placed. Sometimes this is before eating, sometimes mid way through her meal, and sometimes after eating, almost as if it has become some sort of habit or comfort behaviour?
Thanks again, for your answers,
Mary
Since you said her behavior is not like other bats, will it relate to some neurological diseases? even caused by infectious agents? toxins?
Hello Prof Yi-Ning Chen,
Thank you for your interesting answer. We have had this bat since mid summer and only put her in a vivarium with another female common pipistrelle 2-3 months later, after which she had not changed, habit-wise, still appeared to be healthy (coat, appetite, energy level etc.), and this was following advice from a bat expert, as we were aware of a possible infection risk. The other bat has not yet displayed any similar symptoms; nor have an others that we have seen ourselves, although another local bat group colleague had also seen this behaviour in a pipistrelle. Toxins are also a possibility, although she was found in an urban setting an there are no factories or other industry for miles. However, who knows what chemicals people contaminate the environment with?
This has given me further terms that I can use in my literature search regarding this bat; I will add to this column anything that I discover and would be really interested if any other RG members have any relevant information regarding this aspect.
Thanks again,
Mary
Fast circling could very well be due to an internal ear problem, as was already proposed. If the circles are always in the same direction, this is certainly what I would suspect.
Hello Marie-Josée,
Thank you so much. I have just viewed several videos taken at different times, and she always circles in a clockwise direction. Very interesting; how do you think she would have developed this problem?
Thanks again,
Mary
The most likely cause would be damage to the inner ear from trauma and/or infection.
Update:
The more I read, I think that it is a vestibular problem. The bat in question should be hibernating, but wakes much more often than the other bats. She drinks, eats, and goes back to sleep. When she wakes, it could be 9am, 2pm or the more usual time around dusk. I found this in an online posting for owners of dogs and cats:
'In addition, your pet may opt to sleep on the floor rather than on his pillow or a sofa because the hard unyielding surface will help him to reduce being awakened by the vestibular signals triggered with subtle head movements and position changes in sleep.'
http://vestibular.org/sites/default/files/page_files/Vestibular%20disease%20in%20dogs%20and%20cats.pdf
She does sleep on the floor of the vivarium rather than in the more usual posture of hanging upside down on the mesh 'wall'. I am suspecting that she is waking herself up. In this article, ataxia is also mentioned. This bat does not usually walk in the same way as other bats, although if she wants to get somewhere special, she does better. She, to our knowledge, has never flown, despite my efforts (discussed on ResearchGate).
I have found interesting articles about star-gazing and circling (which she does) in rodents (not the same family as bats, but interesting all the same).
As she is eating and drinking and interacting with the other bat in her vivarium, I feel that although she would not survive in the wild, she has a reasonable existence with us. She has been 'an educational bat' at talks (as agreed with English Nature licensing), seems comfortable at being 'shown' at the end, and has had her picture in the local paper.
- Badges
- Science topic
- Similar topics
- Biological Science
- Physiology
- Physiological Processes
- Stress