Bats are very sensitive to lights, so it’s likely they’ll be put off by having bright lights shone around. Filtering red would make it less intrusive, but then less efficient for you to see them. Most bat studies use bat detectors, there are ones that can autoID too, something you could never get from watching things flicker about. I enjoy watching bats silhouetted against the sky as the evening gets dark. If you really want to see bats naturally at night then your best solution is a thermal camera, which are getting cheaper all the time. You’d need one with a reasonable number of pixels and a decent frame rate as bats move rapidly. You won’t see more than bright blobs flitting about, but you’ll see how many there are and the different flight patterns they exhibit as well (and their reflection in any lake surface). Very cool to watch.
Peter
Hi,
Yes i've had numerous bat detectors in my time. The auto ID features of the accompanying software can be very hit and miss.
This is mainly because 1 species going over open territory can sound identical to another on a feeding buzz, or in a dense environment.
I do my analysis manually, and it works well, although time consuming.
What I do need, however, is to see what the bats are doing when I record their echolocation, thus this thread.
Thermal imaging is ok, but are such a narrow field of view, that the bats need to be some distance away to view them properly, and typically are then out of range for the bat detector!
So definitely a colour filter, and definitely a wide angle torch beam. The range only needs to be 30m - 50m. All I'm looking for is an idea of size, where they are, and their behaviour.
The cheap green LED torch was ok, I certainly saw the majority of the Pipistrelles I recorded, and it works fine for Daubentens surveys. (Daubentens move hovercraft like over calm water, so only 2 dimensions to worry about!. Thermal works good for them also)
I have a fenix tk32 to try next time out. The red led looks brighter and wider so may well be the best of what I have.
Failing that, the "seeker" mentioned above would be worth a try, but perhaps the cost is a bit much. We'll see.
Trying to make sense of what's going on, in darkness, with a multitude of clicks and buzzes going off in your headphones, and bats whizzing past at high speeds with amazing manoeuvres. I obviously enjoy it as a hobby/challenge! But I just need to improve the odds slightly.