Customer has a front porch that seems to be the perfect night roost. Brick house on two sides, lattice on third side, open on front: very cave-like. Bats are roosting on a wooden lattice that covers an old window. I suggested using window insulation film over it. All surfaces are painted and would probably be stained by use of hot sauce. Somebody suggested cayenne pepper in vaseline; would that stain? I fear that there's no simple solution, and he'd just be moving them from one area of this porch to another, although the current roost is right next to the door and completely unacceptable. Probably just a few bats, but if anyone has any ideas, I'd appreciate it.

Dave,

Focus on changing the environmental conditions versus the environment. Have the client try air movers for several days pointed at the favored roost sites.

Would something as simple a leaving a porch light on do it?

BigBob,

The light should have no effect on the bats, especially if they have the a nook or corner they can tuck themselves into. The draw for these areas is they protect the bats from weather, wind, and predators as well as good thermal conditions thus allowing the bats to rest and digest their meals before leaving to feed again and/or return to their primary roost site.

Not sure about your area but that should be a male colony. I would go with a bag of mothballs tucked in the lattice and a small fan to stir up the air.
Part of bat work is changing the habitat. A dark screen behind the lattice, even take it down for a few days. Disrupt the roost and they will move on.
A net or screen bat door over the latice will push them out as well.

Why should it it be a male colony ? Mothballs ? ... I'm not sayin anymore ... Wonder how many of you guyz are biting your tongue here ? Did I miss something ? ..

In most states, using mothballs could risk losing your license.

Use of any pesticide is limited to the label instructions unless you get a permit for off label use.

If you do not have a pesticide license you may also get into hot water.

BatScat, on the other hand, is labeled for use on bats, but I do not have much faith in it.

As others have stated, creating air movement would be recommended.

Dave, I had a similar situation, although perhaps on a smaller scale. It just so happened that there was an electrical outlet right where I needed it. ( It was even operated from inside the house ) I took a string of white lights and hung them right where the bats were roosting. It really looked good from the street and they never had a bat problem again. ( Maybe it's because the lights were shaped like over-sized mothballs )

Yeah, the mothballs are a no-go, especially when I realized how hard it is to remove them from the moths!
Eric, would a household pedestal fan work?

Dave,

The basic idea of the fan is pushing the thermal stability out of a zone they can or want to deal with.
If the fan is strong enough it additionally could make them have difficulty flying or maneuvering in this tight area.

I think that as many folks have experienced there are many ways to make them move the questions come down to
how long and at what cost or disturbance.

If they have strong affinity I've had folks do fans, sprays, lights and things I won't mention and the next night the bats would be there.

Some folks would rather have lights and fans running than see a few bits of guano, while others seem quick to dislike the idea
of the methods over the minor irritation, usually depends on colony size.

I have porch roosting Pallids (4-5 other species as well) and get this a ton, working on an alternate solution that we have running trials on, but offering money back guarantee.

I think affinity is one small word for one massive concept in our field with all species.

Strong affinity means they are going to fight harder and this means lots of "fun" trying to work a resolution.

If say the stronger the fan the better possibility.,,,

.02

Justin

David,
Can you post a picture of where the “Bats are roosting on a wooden lattice that covers an old window”? For me, a couple of pictures is often more informative than a five page explanation.