Bat House Forum

[petrie4031]

I'm not sure exactly where the bats are living but they've found an entry point between a brick front and vinyl siding where they meet. I love them for the natural mosquito removal but I'd like to relocate them away from my house and into bat houses in the backyard. My plan is to drape the entry point with a mesh once they've left for the evening so that they can't get back in but have a way to get out should one be left behind. After a few days, I'll permanently seal the hole. Is this a good plan?

[Joe Spencer]

What you're proposing is called an exclusion. Yes your off to the right start in your approach. For the benefit of others we'll do our best to clarify: If there is only a single entry and exit point being used it makes an exclusion much easier. Check all sides of the building for any guano stuck to the siding, window sills, ground etc. to help eliminate other entry/exit points. It is always better to approach an exclusion as having a nursery colony whether or not they're a bachelor colony. In North America and Canada this is best done in the early fall when weather is still relatively nice for you and the bats' foraging. If you feel you must exclude them earlier you can do it the last week of summer but try to resist it and instead build/acquire/erect bat houses prior. Young bats have slightly better skills in the fall and can better navigate the mesh one way exit. If you do it too early you risk having inexperienced young trapped/dying inside. Myotis bats and their cousin species do not hibernate in buildings over winter. Big brown bats do. If you have the time and resources, it is recommended to put up bat houses ASAP/prior to the exclusion so the bats become familiar with it/them whether they use the bat houses or not for at the time of the exclusion you will have an alternative roost(s) ready. Additionally, it is a great idea to do an exit count (late in summer is fine for this). Lie on the ground on a clear nite as close to the building foundation as possible a few feet left or right to the bottom of the entry exit area. Using the sky as a background at a slight viewing angle (better more accurate on clear sky nights) and using insect repellent if needed, do an exit count. It is best to not look directly at the exit but the sky background next to it to get a more accurate count. Do your exit count as close as possible prior to the exclusion night. Do a before after exclusion count and they should be quite close. When you haven't seen a bat exit for 10-15 minutes after the last bat exits, your tally is accurate enough. Remember both nights need to be relatively warm seasonable foraging nights. Although the latter counts are not necessary, it is lot of fun and you learn so much about them with peace of mind knowing most of them got out safely. Check your previously mounted bat houses over the next few nights and maybe you will get lucky and have a surprise in them. It is also possible one or more bats may have relocated/utilizing the previously erected bat house before the exclusion. Either way you've done your best to help the bats as well as having them out of your dwelling. A few days after your exclusion/mesh placement, I would do one final exit check to see if any more come out for they may have another entry point you're not aware of. If you see no indication of bats leaving your dwelling you can make repairs to seal them out. All experienced forum members If you have the time I would welcome your suggestions to add/modify this based on your experience to form a BHF Wiki-type post to help newcomers. I may change the BAT HELP section to BAT HELP Bats in buildings read first etc. http://www.batcon.org/index.php/bats-a- ... intro.html


Good luck...

[petrie4031]

Joe:
Thanks! I really appreciate your thorough response. I'll start building a bat house immediately. My bedroom window is 3 feet from the entry point so counting them shouldn't be an issue. I don't know much about bats but they are fairly small in size. They've been using the roost for 10 years and I assumed they hibernate there as well but if not, I can certainly wait until winter to seal. They are fascinating creatures so its time for me to learn more about them. Thanks again.

[cloudman75]

Petrie 4031,
What state do you live in? That would help determine what species of bats you might have. I have excluded Little browns in the past from my dwelling vetilation louver. They used my bat house the first year after hibernation and every year since. I'll add more later once I know if applicable to your bats.
Your plan looks like a good start to me.


Frank

[petrie4031]

I live in Western New York between Niagara Falls and Lockport. I started staining the wood for the bat house tonight. I'm thinking that the house would be best if it were on a poll by itself rather than in a tree, yes?

[Markcuda]

Yes, a pole is a great idea, and please, don't put it in a tree.

[Terry Lobdell]

Petrie, I agree with what Joe told you..........and you are right about the pole.......definitely don't put it on a tree........

The closer you put the bat box to where the bats are presently entering and exiting the building the quicker they will start to use the bat box.......