Bats in my belfry!

Well, not a belfry exactly, more like the gable. And while I am theoretically in favor of bats, given they eat a ton of bugs, along with bats comes....yup, you guessed it, guano!  All over the concrete, the little black bits that look like mouse turds.

I certainly won’t try to kill the bats, but any thoughts about disease given proximity?  Other risks?  Should I put some wire up there to discourage/keep them out?  It has gotten old cleaning up after them.

Guano on concrete

Awesome!! In lieu of relocating those bats to my place an option may be to place something like wood chips under those chiropteran friends collecting their nuggets of black gold so it's easy to rake up and compost!

(I looked up chiropteran, that sort of thing doesn't stick around in my brain)

Disease may only be a problem if you have young children who may pick up a fallen bat.  But they won't attack you with rabies or anything.

http://www.batcon.org/resources/for-specific-issues/bats-human-health

In a lot of places it is illegal to disturb a bat colony...check your local jurisdiction. Also, depending on where you are and the type of bat, they may be migratory, and leave as the weather cools for a warmer location. Ideally, this is your situation and all you have to do is wait a few more weeks and they will leave, allowing you to secure the building.

Enlisting the help of a local bat expert to help identify type of bat, it's migratory potential and the colony size would be your best first step.

If possible, film the nightly emergence so you can pinpoint ALL their exit points (doing the same when the "go home" is ideal) and the size of the colony (count them). This allows you to determine what exactly you are dealing with and where you need to secure the building.

Assuming it is legal, you have a few options, although they are all finicky and a bit labor intensive.

Method one: install an appropriately sized Bat Box that will ideally house the entire colony in one box and locate this somewhere on your property so you can still benefit from their bug catching prowess.

If possible locate it on the house or very nearby - note the location, height and orientation of the portion of the house they use and replicate it (they carefully choose a specific number of sun hours/wind to meet their thermal needs).

Method Two: using "bird netting" (monofilament mesh, 1cm squares) and fully secure it to the roof and building edges so it drapes down at least 10 feet. This allows them to leave (they will climb down the inside of the mesh) but they usually seek their normal entrances and do not understand how to climb the UNDERSIDE of the netting to access the attic. In your specific instance it may need to be tacked down at intervals along the bottom so there is no more than a few inches open for escape.

Method Three: Block all but one of the access points, create a tunnel of mesh or fabric that funnels the bats into a ventilated container. Once no bats have emerged for 20 minutes seal container (to prevent escape, but maintain ventilation) and relocate IF LEGAL IN YOUR AREA.

All methods must be repeated for several nights to ensure everyone is out, followed by a very careful inspection of the attic space before permanently sealing the access points.

Depending on your location various diseases may be present in the colony, of greatest importance is the possibility of rabies (a young man died here a month ago after swatting a bat - never realized he had been bit/scratched and never sought prophylactic treatment - by the time they figured out what his illness was the treatment window had closed). The other big one is a fungus called white nose disease that is devastating bat populations in North America and is highly contagious, bat to bat. This is why in many jurisdictions relocation is illegal.

Let's assume no eviction was required and they migrated south...now you must secure the building and clean up the mess. Please use proper breathing protection and suitable, disposable coveralls when dealing with fecal matter of any type, in an enclosed environment. Bag all contaminated insulation, and dispose in a manner that is legal in your jurisdiction.

In MOST cases, suitable caulking will be your tool of choice to seal their entrances. For larger openings, hardware cloth (galvanized metal mesh, 1cm squares) installed with SCREWS through a sandwich of house/mesh/wood.

Good luck!

Artie, we have a bat story! The upshot is move them to a tall tree or pole AWAY from your home

When we bought our last house they were living in the louvers in the gable of the attic...it was a two story house.  They started slipping into the attic, would get stuck and it would be like mice scurrying around in the night.

My husband built a beautiful 'bat box' and mounted it right outside the gable over the winter while they were elsewhere.  He screened over the louvers to keep them out.   It worked! They moved into their new home and expanded the colony to overflowing...and they did not get in the attic again.

BUT, this was all right outside our bedroom window so about the time I go to bed, at dusk, was when they start dropping out of the box for the night...not my favorite sound for a good nights sleep.  ...and there is the scritching sound while they settle in.

We had a sleeping porch/balcony off of the bed room then that we had screened in and would sleep out there in the hottest part of the summer.  I found what looked like dead bed bugs a few times on the floor around the bed...turns out they were bat bugs...related to bed bugs but exclusive to bats and apparently only suck bat blood....and there were the cone nosed kissing bugs!  I was bit one night and had no bad reaction BUT I blame the bats for them also as I had not seen one in forty years living fairly rough in the Ozarks.

We were able to compost the bat poop in place under their house...I would just throw some weeds over it every few days...good stuff!

I appreciate bats...still kind of look at them as mice with wings but they are so much more useful.  We are eyeing some trees for a bat house here in town...well away from the house.

This probably repeats what Lorinne posted, but here is more information about bats in buildings:  http://www.batcon.org/resources/for-specific-issues/bats-in-buildings

I encourage all bat enthusiasts to join Bat Conservation International.  Their work is so valuable! https://www.batcon.org/join/become-a-member

25 years ago I helped my landlord put wooden siding on the side of his rental house, that did not have any doors or much reason for anyone to go there. The bats had been living on a different side of the building, where their poop would drop in a paved area and in front of the entrance door.

 We placed the siding, using wooden spacers that gave the perfect size gap for that species of bat to utilize the space. Ted knew quite a bit about bats and he wanted them there. This was the east side of the building. He said that they like the morning sun but you don't want hot afternoon sun. That's why he didn't choose the west wall .

Ted obtained some copper trays which were placed against the siding, to capture falling poop. It was used on his orchids, which were his chief bragging point when other gardeners visited his greenhouse. Every tour included a look at the bat wall, and a little spiel about the importance of protecting bats and the horrors of chemical fertilizers on delicate orchids.

I have swallows in my garage, their shit is sticky so i screwed a piece of wood under their nests. Catches 95%. Remove it once a year. Good shit!
When they weren't there, there were many more musquitos in the summer time.

I'd build a bat box and hang it right there where they roost.  Then, after they've moved into it and called it home for a few months, slowly move them to another location and temporally seal off that space so they don't re-colonize it.




Here's a fancy one, cut with a CNC machine.




This guy is a goober, but you've got to appreciate his enthusiasm.