Bat House Forum

[Canute]

Trying to determine if these bats are Little Brown Bats or California Bats (Myotis californicus). Can anyone help me confirm?

[Terry Lobdell]

Might be hard to identify........I am not familiar with CA bats so I can't help much, sorry!

[Joe Spencer]

Hard to tell with the darkness of the body in the photo however, the ears look a little more elongated than that of little brown bats so maybe it is a Myotis californicus. Not sure though...

[Canute]

So I've been reading a ton of literature (mostly research documents) to try and determine what species of bats I have. As you guys have said a positive identification seems near impossible. I have however narrowed it down to one of three species and in my opinion they are (in order of most likely down to least likely). California bats (myotis californicus), Western Small-Footed bats (Myotis ciliolabrum), or the Western Pipistrelle (Parastrellus hesperus). Based upon the observed foraging habits, local habitat, coloration and roosting tendencies I really think they are California bats but...???? I am however disappointed to read that both California bats and Western Small-Footed tend to have very small nursing colonies (under 50 individuals with 10-15 being most common) so I'm hoping they turn out to be Pipistrelle's which, from what I read, will amass in huge nursing colonies. Guess I'll just have to wait and see what happens next spring!

Another interesting thing I've noted. My bat houses ALWAYS have one bat in one house and two in the other. I've noticed that every night the bat in the "bachelor pad" takes flight first...he (presumably a he) then does one circle around our tree line then proceeds to fly over our neighbors property. He then passes back over us and crosses the tree line over to the neighbor on the other side. These are direct flights with no sign of feeding whatsoever (little dudes on a mission!). After this pattern is complete he then goes into foraging mode directly over our field. From take-off to foraging is usually around 10-15 minutes. It is at this time, and ONLY at this time, that the other two take flight and immediately join him in foraging (no scout flights for them). Anyhow, not sure if it means anything but sure seems as though the presumably male bat is checking things out before telling the ladies it's safe to come feed! Either way they are pretty dang cool to watch in the evening while having my beer and enjoying a smoke.

I'm going to re-post a couple of close ups here that I've included in other posts in the hopes that someone who knows more than I might check the topic and give me some insight.