Real Questions on Excluding Bats From Our Customers

1. I have a question regarding identifying bat droppings. We have what I assume are bat droppings in our attic. It is the 3rd floor attic of an old house. We have two large new windows that have slowly become streaked with yellowish clear stuff, and the other mouse-looking droppings are falling below these windows. Would you recommend opening the screens of these main windows to let them out or would that just make it harder to find where they are getting in?

Bat droppings will appear to be black grains of rice. When crushed, you will see shiny bits of insect fragments. One way to start finding some bat entrances is to stake out the structure at dusk (7:45-8:30 PM) and witness the emergence. Try to align yourself so that you can view two sides of the structure with lots of sky in the background. Bats will be seen against the light sky, not dark trees. Bat numbers will begin dwindling until November when most should have vacated the building for the winter. This is a good time to repair all the entrances (and then some) noted at dusk.

2. This fall, we had a bat flying around my bedroom. Fortunately, we got the bat out without harming it. What really concerns me is that one of my neighbors around the corner had a bat in their bedroom Saturday night. Does this mean that there is a colony in our area, and that these incidences may occur more frequently? Is there anything we can do?

Having a bat in the living spaces does not immediately constitute a health hazard. During this time of year bats are quite curious and go about "checking into" places which could be future roosts. Occasionally some may take a wrong route and enter through a handy door or window and end up "stuck" in a house. If you have repeated problems, then perhaps the structure or some neighbor's structure already has an established bat colony in the attic space, for example.

4. I have purchased two bat houses and placed them according to instructions. How long does it take for bats to come to the houses and is there anything I need to do to attract them? I live on an acre of land in south Florida. Have a variety of trees and bushes plus a 40'x50' pond. What will it take to lure a colony of bats to the property?

If placed in good habitat in the early spring, it is common for a few bats to begin using our box design the first season, and even within the first week. If the box does not contain bats after the second season, any of three problems might exist. The box is not getting enough sun, a seal has opened allowing too much ventilation, or the box is in poor habitat. If you already have noticed bats around the property in the summer at dusk, your only problem will be choosing the right
site.

5. I recently acquired a Pa. Brown bat that has been dislodged from his hibernation roost. Being a fascinated lover of bats I want to do all that I can to keep him alive and healthy until I can release him. I have set up a large aquarium with a mulch bottom, large tree trunk for him to hang from, fresh water, meal worms to eat and a nocturnal heat lamp for warmth. Am I on the right path or do I need to do more to ensure he continues to live until I can release him?

In Pennsylvania, bats will move out of hibernation and resume feeding and reproduction in late April and early May. Hopefully you are not possessing a pregnant female (bats mate in the Fall, then have pups in the Spring, after hibernating.) If so, you may be jeopardizing both the mother and the fetus with improper care.

Carry the bat out (in a gloved hand, or in some other fashion where you do not come in direct contact with it), and place it on a tree trunk out of reach of evil house cats and other marauding predators. That's it. No heat lamp, no mealworms, no mulch bottom. Some of those things may actually be unhealthy for the poor critter (mulch is a good place for mites to breed). Unless it is suspected of human contact and needs to be kept under observation or tested for rabies, let the poor thing go. Care of captive bats, even healthy ones, is a tricky thing and should not be attempted by amateurs. It may be important for the bat to feed heavily soon after release, and if the weather is rain every night for a week that might be bad. I would suggest releasing the bat as soon as possible but in a raging downpour it would be inappropriate.

Note that in all states you must have a trapping permit or rehabilitator license to care or even handle. Fines in theory could go as high as $20,000 for a federally endangered species. (An F.E Indiana bat looks very similar to a common little brown.) On top of that, disturbing wildlife in a cave in Pennsylvania and most other states is a violation of their respective cave protection laws. And hopefully the hibernation site where you retrieved the bat was not on state or federal land, as that would incur additional charges. Don't panic, no one is going to "turn you in." These laws are in place more to prosecute gross ignorance, not one person who thought they were "doing the right thing."

6. I live in a second story apartment building. Well, bats also reside in the walls of my building. They are in the walls next to where I sleep and the odor is coming through the electric socket. I am getting headaches from it and I need to get rid of them.

Your landlord has a somewhat serious problem here which could eventually impact the health of the tenants. Any wild animal in close contact with humans is considered a problem these days. This certainly is a violation of some local health codes.

Sprays and pesticides do not work on bats as a permanent fix, and the quantities required to be effective are harmful to humans. So if you though you had it bad when you had bats....

Any reputable local pest controller will insist on sealing the bat entrances to the structure, which must be done before April 1 at dark after bats have left, or this November through April when bats are not present in the structure. Sealing April through October will trap flightless young in the structure and other adults, causing an even greater health problem.

The good news is that proper sealing is 100% permanently effective if done correctly, and incredibly effective even if done incorrectly as long as an alternate roost is available, such as a bat box. Bat houses have been proven to be so effective that some bats will often use them over their present roost structure without any sealing attempt of the original structure.

Bat boxes combined with a sealing strategy is the only approved way of dealing with a bat/human conflict. There are still pest controllers out there who use bat problems as huge money makers, so I urge both you and your landlord to review eviction information in our website and others such as Bat Conservation International before hiring any outside contractor. If the colony is significant (it sounds like it) and located in Pennsylvania, I may be able to arrange assistance through various government agencies.

7. I live in a small rural Kansas town and would like to attract bats to my yard for bug control. How do I know if there are any bats in the area and if it would do any good to put up a bat house?

Pay special attention at dusk in the summer near ponds, rivers, or nearby streams. If you spot any sort of "bird" fluttering somewhat erratically, it is actually a bat. This means your local habitat is suitable for bats and a properly constructed and placed box should be successful.

8. Your article on what to look for in the construction of a bat house was very informative. I had recently looked at a bat house at a local farm store. After reading about properly built houses I was very glad I didn't waste my money. Is it too late in the year to put up a bat house?

By properly installing a box in mid-summer, a few bats will investigate and even move in by fall if the box is in good habitat. Look for solid use next spring/summer.

9. Help!! We just bought a very old beautiful house. I have one very large fear and that is of bats. Our attic is full of them. Hundreds, maybe thousands of scary bats. What do I do?

By observing the outside of the house for 45 minutes after sunset in the mid-summer, you will be able to observe the nightly exit flight. By individually counting the animals you will have an estimate of how many alternate roosts (bat houses) must be installed. More importantly, you will notice the bat entrances which need repaired. Bats WILL NOT chew new entrances into your attic. Repairs should be made in November when all bats are out of the attic. 

...We have sealed up the cracks, we thought, but they keep coming back. They come in the house and hang all over the place, and even on the outside of the house.

This means bats are desperate for a suitable roost in your area. By providing alternate roosts (bat houses) you can manage these animals out of the way, but still benefit from their presence.

...It seems they get in the most when we go outside and look at them, then they come in the house as if to say "I know your scared of me now I will get you." Please help is there a chemical I can get to run them away?

No chemicals. No "sonic pest repellers", either. Any company which tells you different is about to rip you off. Remember, bats are mammals just like your pet dog, cat, and you and me. Chemicals powerful enough to kill/repel bats also kill humans.

...I am told they have been in the house for about 50 years and they come back each year because of the scent they leave in the attic. My kids come to my rescue each time they get in the house and kill them but that makes me feel bad for killing any of god's creatures. I'm just so afraid of them I feel like I am going to literally have a heart attack when I see one. Isn't there anything I can do?

Relax, bats will not attack you even if your children chase them down. If a bat is in the living spaces, open windows and doors to the outside. Close off adjoining rooms. Above all, watch the bat! One of two things will occur: that bat will fly out of the house, or land. If the bats decides to rest, places a shoe box over the animal, carefully slide thin cardboard under the box to make a lid, then carry outside. Never handle any wild animal with bare hands. The only permanent solution to your problem is careful, systematic repair of the attic. Often it may take several tries to successfully bat proof a building, and bat boxes greatly increase the ease of success. 

10. I've been debating about whether to get a bat house or not. I like bats but after reading about how picky bats are, I'm reconsidering. What's your opinion? I live in the suburbs. I plan on attaching the bat house to the house on the second floor (outside surface is wood), under the eve where it will get about 5 hours of morning sun. The nearest water source is a small stream about 1/2 mile away and there is a good sized pond about 3/4 mile away. I know bats are around because my neighbor had one hiding in a 1" crack above their door. I also had one hanging on my screen window very close to where I plan on putting the bat house.

Finally a question requiring a simple, quick answer. You already have bat activity in your area, so bats should have no problem finding a box on your property. Some things to consider:

1) Be careful about placing the box UNDER the eves, as the eves will shade the box and render it useless.

2) Bats have been known to use swimming pools for drinking, so the water might be closer than you think.

3) It is still best to place the box on a post, since you can position the post where it can get the most sun.

11. I was hoping to put up one of your bat houses on my 1.5 acre lot (half wooded, half open) to help with the insect problems and to help the bats, which I occasionally see flying around at dusk. The problem is that there isn't a permanent water source nearby, though there is a good sized river about 2 miles up the road. I wonder how important that water source is for recruitment, and whether an artificial source of fresh water (large birdbath, etc.) would suffice.

If you have noticed bat activity around the property at dusk, bats will have no problem residing in a properly placed (and constructed) bat box. Sounds like your area is good. Generally, for a very large colony the closer to water the better. A nearby swimming pool might already be sufficient for bats to get a drink.

12. My husband and I put up a bat house (using instructions supplied by our local Science Museum) last year, but have not had any bats move in yet. Can you give us some advice on attracting them (someone suggested using fresh guano - do you think this is necessary?).

If the box has been up for more than two summers, and you have not seen any bat activity yet, the box has:

1) poor placement
2) poor design
3) poor construction
4) any combination of the above.

If you have all of the above going for you, there is absolutely NO NEED to "bait" the box with any lures. Please see the following sections on our website about spotting bad bat box designs. Remember, some of the main reasons for box failures is not enough sunlight, improper exterior paint color, and incorrect baffle spacing.

13. Will putting a lit work-light in the area where I think bats are living make them want to find another place to live, or is this just an old wives tale? I did not see it mentioned in your discussion on evicting.

Bats may move away from the light, but will easily find some crevices to hide in. Do not bother with temporary "fixes". Install a good bat box, seal the attic, and your bats will be safe; not in another neighbor's house.

14. Do you sell bats/bat houses? Or know anyone who does? We're looking to bring bats to the woods behind our house to control the bug problem.

Our original bat house design has a 95% or better occupancy rate or better when installed properly in good habitat. Generally, if you notice a few bats feeding at dusk you can be assured that the surrounding habitat is suitable. In a wooded area, sunlight is the greatest placement concern. Any box of any design will fail unless it is placed to receive at least 7 hours or more of direct sun, preferably morning sun.

You will find no company in the U.S. or Europe which sells bats, as it is against state and federal laws to physically hold onto them without proper permits (i.e. a wildlife rehabilitator permit) . Also, bats are highly territorial with excellent homing abilities and have been known to find their way back to a specific roost after being moved up to 400 miles away. So, even if you found some bats, they would not stick around. The best you can do is properly construct and install a bat house to encourage local bats to take up residence.

15. I have been searching for information concerning safe relocation of bats. I am a homeowner. A family of bats have taken up housekeeping behind the shutters on the upper level of my house. The bat droppings are a bit of nuisance but the real problem is the noise. Every morning they create quite a racket getting back into the shutter crevices and wake us up in the process.

I have been tempted to remove the shutters but they are hard to get to and I don't particularly want to get that close to the bats. This is not bat hysteria. I would not want to get close to any flying animal. Not to mention, it would leave the bats homeless. I considered putting spot lights on the shutters thinking that they might seek other shelter. Do you think this would help? How about putting up a bat house? How do you get them to relocate?

Sounds like you have a fairly simple project at hand. One suggestion is as follows:

1) Install a  bat house nearby on a post where it gets plenty of sunlight. This should be done before October so that bats will find your new box. Bats roosting in shutters indicates that the animals are somewhat desperate for a suitable roost in your area.

2) Bats will move out of your area (usually) by November. Go to the shutters previously occupied by bats. Install a spacer or somehow tie or rig the shutters to set away from the house at least 3 inches (more is better). This larger space now makes the roost undesirable to bats (unless they are truly desperate). Bats prefer crevice spaces 3/4'' or less.

3) Bats will most likely move into the bat box next spring. If you do not see activity in the box after two seasons (the end of next summer in this example) your box is too shaded.

Another idea is to paint the shutters white. This will cool off the roost and make the area undesirable to bats. 

16. I have spent a couple of hours on your website. It is most informative. In the last 2 weeks I have been awakened by commotion in the house (around 2:00am) and when I turn on the lights I see at least one bat flying around. I have killed two already simply out of anger and fear and simply put a dead bat accounted for is better than a live, unaccounted for bat that can terrorize us again! How many more can there be? I live in Chicago, IL. Do these bats bite you in your sleep?

In late summer and fall bats seek alternate roosts by investigating cave, houses, and just about anything that has an "entrance". Make sure all obvious entrances are closed or have screens.

The next step would be to carefully observe the structure for 45 minutes after sunset and see if bats exit the structure. Once entrances are identified then systematic repair of the structure can begin. This is usually in November when usually no bats are present in that type of structure. 

Bats will not attack you even when chased. They will attempt to bite during the first few minutes of being handled. Little brown bats, by far the most common "house bat" in the United States, if not the world, have never been proven to transmit any disease to humans and are generally not powerful enough to break human skin. As with any wild animal, you should refrain from directly handling the bat and use gloves for your own protection if necessary. 

17. I am looking for raw bat guano to be used to lure bats to my new bat house. Do you sell this? If not, can you tell me where to get it? I live in Wisconsin and I believe we just have common bats.

I would love to sell you hundreds of pounds of guano and take your money, but frankly just having the droppings will not lure bats into any box. This was an old idea now perpetuated only by manufacturers of low quality bat boxes. Attention to box construction, design, and installation makes the difference.

Any structure needs to meet very strict requirements for bats to consider using it. First, if the box is not "bat approved" by Bat Conservation International, you're in trouble. Then see our sections entitled "Why boxes fail". Given all that you may be able to refurbish your existing box so that it is more bat friendly.

18. I purchased one of your bat boxes in the spring. I installed it and have pretty much the perfect site for one. I used a compass to orient it and set it at the right height, it gets the morning sun 5-6 hours, followed your directions, etc. I live on 4-1/2 acres with lakes to the east and west within 2000 to 3000 feet. But what's been troubling me is if it is so important that the box absorb heat from the morning sun in the summer, then why do bats like to inhabit cool and moist locations like caves? I live 20-25 miles east of St. Louis, MO. I do not have any bats in the bat house yet. But I do see 2 or three flying around the area of the house around dusk. I've been checking it during the day.

Bat houses are almost always only summer homes for bats. Critical in the spring when pregnant females arrive searching for a place that will be warm (about 100°). Energy can be spent nursing young instead of keeping warm. Several other factors also contribute (the crevice widths and roughness, etc.) but if you place even the best box in the shade, it may never house bats.

During the summer in northern states, relatively few bats are found in caves and abandoned mines. Those are usually males using the site as a day roost, and may not be loyal to a particular site from day to day. However, certain species in warmer latitudes take advantage of ceiling pockets in caves to trap body heat. In this way some very special underground sites are very important (and sometimes very large) maternity roosts.

Typical "house" bats, big browns and little browns, in the northern states may travel hundreds of miles in September and October to their hibernation site; a natural cave or abandoned mine. There they require stable temperatures between 38°-48°, fairly high humidity, and no disturbance in order to survive the winter without feeding.

During that time of year bats are "checking out" alternate roosts and should discover your new box. Look for better results next summer and fall. In your local area there may be an abundance of available roosts which will impact the traffic of your new box.

19. A friend of mine recently bought an older home in Minnesota that has a bat colony in the attic. On your web site, you indicated the best time to plug entry routes is after November when bats are not present. Where do the bats go in the winter?

I was under the impression they would just hibernate in the attic during the cold months. I'd like to seal the holes, but naturally don't want to trap any bats inside. Any advice?

Generally all bats in the northern U.S. must either migrate south or hibernate in a suitable natural cave, abandoned mine, or abandoned tunnel to escape the northern winter when food is very scarce.

Most species of hibernating bats in the northern U.S. require very stable temperatures (38°-50°F) throughout the winter. Certain species, like the common big brown bat which is typically found in barns and many homes during the summer, are hardy enough to tolerate great temperature fluctuations and human disturbance throughout part of the winter. In some areas it is not unusual to find bats in attics unusually late in the fall or very early in the spring. This is probably the result of these animals improvising with manmade structures due to the lack of suitable traditional hibernation sites nearby.

If you suspect bats still remain even though it is December, you might hold off your exclusion work until January or February. You can also seal all the entrances except the main one, and install a temporary "one way door" system until summer arrives and you are sure bats are no longer exiting.

Installing a properly constructed bat house in the right location also increases the chances of success and avoids "infestation" of other nearby structures.