After posting the question I found this great site that answer some questions.

http://www3.gov.ab.ca/srd/fw/bats/bathouseff.html

We've had our bat house up for about five years, still no visitors. I haven't done the adding guano to attract them thing, just hung it and left it.

cantstop

we don't have the right kind of yard/location for them so I haven't even tried, but I'd do it in a heartbeat otherwise.

Here is a link that might be useful: another good site:

We put one up the spring of 04 in our backyard on an oak tree as high as I could reach on the ladder. No sign yet, and I'm not entirely hopeful as I heard the house should be in full sun.

I just got a good book - America's Neighborhood Bats, by Merlin Tuttle. He has descriptions of the most common bats, along with distribution maps for each one. The maps also show the distribution in Canada and Mexico, so it might be helpful to you still, madtripper.

He says sometimes you have to experiment with painting your bat house a new color (darker colors in colder climates, lighter colors in hot climates), or putting it in an area that gets more sun, etc. He even has a picture of a bat house stuffed so full of bats that they can't all fit into it. He says that the house had been empty for five years before it was moved to a location with more sun. Within three weeks, it was full. He says that too little sun accounts for 80% of failure in attracting bats.

I hope that helps. I'm really hoping to attract them, too:)

~Mesquite Ent~

In Britain they say that usage can be quite low, but you are most likely to get them moving in if the bats already fly in the area, and there is a lack of natural roost sites. Our boxes are usually sited on trees or buildings rather than a pole. I have put up my first ones this winter, and am hopeful! I have recently discovered that bats use an old bird box a few gardens away for some of the summer, but I haven't actually witnessed this.

Here is a link that might be useful: UK bat site

I have! About ten years ago I bought two bat houses at a local agriculture fair in Connecticut. (I had never seen or heard about bat houses before that.) I mounted them both to the side of my garage - about ten feet off the ground. One was exposed to full sun, the other shaded. After about two years, the bats finally came - and lots of them. I now have four newer bat houses, and had to move them away from the house because they can find a cranny in the eaves in your house and then you're in trouble. I mounted the new houses on poles (this was a real pain). But now the bat houses are full of squeaking bats from about April till mid-November, then they go somewhere to hibernate. I have a nice pile of bat guano on the ground beneath each house to add to the compost heap too! They do move from one house to another depending on the temperatures. They are cool to watch - we watch them fly around the acre of cleared woods that surrounds my home.
Pru

Hi madtripper, I'm zone 5. I've had success. I have some bat house plans that are functional that will work for you and I would be more than happy to share them with you, just e-mail me privately. We made a total of 8 of them. Several we kept and installed and several we donated. The time to make them and get them up would be right about now so they are in place when they return this spring.

We originally purchased several bat houses that were totally inhospitable to bats due to the fact that they were just way too darn small. You know those cute little things on end caps at stores that show pictures of bats using the bathouse- they lie. Same concept as butterfly houses. Anyone ever see anything other than Japanese lady bugs or wasps using butterfly houses? Unfortunately, I had no knowledge of size requirements at the time I purchased those nicely marketed impractical bat houses. I found a set of plans on the Internet and downloaded those and was quite excited until a man from the beekeeping forum gently burst my bubble. He did, however, send me a set of plans that were very appropriate for the species of brown bats that we have in my area. I did a little poking around back then when I first received my blueprints and learned that I needed to place my bat houses under the eaves at an elevation of around 25' preferably facing sw or se. I believe the height of the bat house will vary from species to species but about 20 seems to be the minimum for all as a 20 foot clearance underneath is required in order for them to release from their upside-down position, unfurl their wings, and to attain lift. Way cool! Makes sense to me.

I learned why many people who install bathouses don't get any occupants. Most mount their bat houses on trees. Bat houses are used as nursery/incubators and they need to be exposed to sunlight in order to create internal temperatures needed for the young to survive (over 100 degrees for many species). On the flip side, you don't want to cook them either so best to avoid installing them facing south. Also, bats don't like to have to negotiate branches and things when they're flying in. This would have been why the man who sent me the bat plans instructed me not to install my bat houses in or around trees.

I picked up a little bit of information pertaining to the color to paint your wood. In my climate, I need to go darker to absorb heat. The color differences are requisite to create the proper temperature inside the bat house. I went with a Knight's armor gray (mid tone) but zones further north might want to try a darker steel gray or a mahogony brown while zones much farther south might want to try a light dove gray or a lighter flesh tone type beige.

Please avoid using any pretreated lumber. For the inside of our bathouses we used rough sawn cedar. We also used a dremel tool and made a few horizontal gouges. There was a method to the madness in that the little bats could get a foothold to move around inside.

Now hereÂs what is interesting, I had no idea so many species of bats were threatened until last year. More than half of American bat species are in severe decline or already listed as endangered- hmmm, could it be due to all the trucks spraying chemicals to kill mosquitoes??? I also learned that bats are the slowest reproducing mammals on earth for their size, making them exceptionally vulnerable to extinction. I also found out that that one little brown bat can catch 1,200 mosquito-sized insects in one hour. Well, that places bats high on my popularity list.

The book recommended above by MesquiteEnt is very good and if interested, you might be able to check it out at a local library-
The Bat House Builder's Handbook by Merlin D. Tuttle, Donna L. Hensley

HereÂs a link to a fancy bat house for anyone who may have a "picky" home ownerÂs association-
http://www.mulberrydesigns.com/vicbat.html

http://www.batcon.org/
Bat Conservation International

Laura - are the bat houses close to a river or large lake? that seems to be an important requirement.

No. No large lake or river on my property. There is a river about a mile away. The presence of a large body of water is not an important requirement.

My bat houses are up under my eaves but I'd like to try one on a stand alone pole and may do that some day. I do have ponds here but there are mosquito dunks in all of them. Plenty of insects for them to not only survive but thrive without a mosquito breeding ground present.

There are well over 900 species of bats. 2/3rds are insect-eaters. The majority of the remaining 1/3rd eat nextar, pollen, and fruit. A few species eat fish, birds, small mammals, and reptiles while three species feed on blood.

If you are interested in trying a bat house, please don't hesitate just because you have no water in the near vicinity. If they like the digs you provide, they will occupy it. It might take a few years but then again I've seen them fill up as fast as one can make and install bat houses too.

I forgot to mention that my bats are the small brown bats. Bats prefer fairly clear and open spaces too, my yard is over an acre cleared. My neighbor put up bat houses too but she has never had bats. But her yard is nothing but huge pine and oak trees.

When the bats fly while they are munching - they circle, dip and swoop in lightning fast circles and loops all around the cleared part of my yard. (I have a huge mosquito problem, which is their main food) They don't seem to fly very high either. They do not go into areas where there are woods. Then they need a clear landing into the bottom of the bat house. I do have any body of water nearby me either.
Pru

Things to do to attract insect eating bats:
Stop using all pesticides and herbicides.
Plant night scented plants to attract moths,
Plant plants of different heights ie ground cover, bushes and trees and climbers.
Have a pond or at least a tub for drinking (by skimming across) or to attract water breeding insects like (sorry) mosquitos.
Don't treat timber in your home with pesticides unless you absolutely have to, and if you do, try to get bat friendly types.
Don't get rid of big trees with hanging bark or cavities as these are often roosting places.
Try to have nectar plants flowering for as much of the year as possible.
Don't fill all the gaps in your eaves etc. I don't know about American species, but British bats do no harm at all to your house. (All British bats are insect eaters)
All British bats are protected and so are their roosts, whether in use at the time or not.

I just looked back at what I posted and I need to correct something, "remaining 1/3rd eat nectar, pollen, and fruit".

Pru, you meant you don't have any body of water nearby by you, right?

I have Big Brown Bats around here (Eptesicus fuscus) as well as Small Brown Bats (Myotis lucifugus). The Small Brown bats are the species occupying my bat houses that drop down and and perform air acrobatics for us shortly after sundown. They are very tiny and delicate in appearance. I have no idea where the Big Brown Bats are roosting around here but they are here somewhere. I am relatively sure we also have both the Hoary Bat (Lasiurus cinereus) and the Red Bat (Lasiurus borealis) in the general area as I sat outside in a lawn chair a few times near the street lamp to wait and watch what swooped in to scope out the insects and have seen those two species. The Hoary bat is strikingly beautiful in that it has silver tipped fur much like a chinchilla. It is also the largest bat I have around here. Again I have no idea where they are roosting. I would like a pair of night vision binoculars. I wish the good ones weren't around $600.

Laura,
I live in a very wet wooded part of the state. There is a stream about a half mile away, but no large lake or pond nearby. The mosquitos are ferocious here in the summer.
Pru

Laura, have you thought of getting a bat detector instead of binocs? You can get a basic one for about £50 at the moment.
Or you might find someone selling second hand night vision binoculars cheaper.

Someone mentioned trees with loose bark or natural cavities...and I believe this is why not a single bat has been seen in our house since we put it up. We are basically surrounded by shagbark hickory and have TONS of bats. I have even seen them through the mild winters we have been having lately. We have plenty of water which = plenty of mosquitoes and other flies, and plenty of bats but they just seem to prefer the other local real estate.

Hey! I missed a product out there on the market that is wildlife oriented??? I am slipping! What, pray tell, is a bat detector and do you have a link to one? Thanks for mentioning this dampflippers!

Dirtgirl! I've got shagbark hickory too and I have noticed they like to crawl up under that bark from time to time.

The Missouri Conservationist Magazine, published by the state's Conservation Department and free to Missouri residents, has exceptional articles on wildlife. The last article I read on bats suggested not only the guano but some fine plastic screening material inside the bat house. The screening, firmly attached to the inside of the house's walls, will allow the little critters to have secure footing. It seems the guano and screening are two very important points in attracting bats to the houses in your yard.

Other important points mentioned were avoidance of shady areas...the house needs 6-8 hours of sunlight per day...and not hanging the bat house in a tree. A helpful touch: a stream or small pond will increase likelihood of bats homesteading in your area.

Here's a handy link to the Missouri Conservationist's plans for building and maintaining bat houses. There are also articles on identification of bats and removal of nuisance bats.

Hey Laura and DG, We are loaded with shagbarks also. Now I know where the bats come from!! I never knew that.

I know this is a very late response to this thread , but I so want to put up a bat house this year!

There seems to be a couple of experience bat folks here, so I hope you can answer my questions. I have heard some people ( in-laws mostly qho like to scare my hubby and I don't feel they knwo what they are talking about!) but I have heard it said that the bat droppings ( guano) and urine is toxic... But then I see guano can be used in compost piles or as fertilizer? If I can get the bats ( and I think I can), can I use the guano in my compost safely if I use that compost to fertilize the veggie garden? I don't really see why a critter who eats bugs would have toxic poo...?

I need to convince my hubby. He's all for the bat house to help with the mosqiotos- and we already have bats trying to stay under a shutter or two.. so I knwo theya re here. Why not hosue them right? But he may freak out if I want to use their poo in the compost.. any knowledgable folks that can put this fear to rest?

Bat poo is called bat guano and is one of the best fertilizer available to make compost from. Bat guano is harvested by the tons from caves and made into fertilizer so it is very safe and GREAT to use. Go online and do a search for Bat Guano.

I have two bat houses on opposites sides of an 80' pine tree. They are about 20' off the ground and the first branches of the tree don't begin until about 40' up. They are 2'X 3'. I have on average about 550 bats in them from late October until mid-July. I have no idea where they go when they leave. The most I have ever had in them is over 1000!
They were living in the attic and I had to get rid of them because of the noise and smell in my bedroom, so I found bat house plans online and built them. It took two years for them to move in. Once they started moving in I fixed all the holes to keep them out of my attic.

Just a note on controlling the mosquito population. One of the most common bats in Texas is the Mexican Free-tail which is what mine are. Unfortunately Mexican free-tail aren't know to eat mosquitoes. That's a shame because I have lots of mosquitoes. :(

Anyway, I do like the nice pile of quano piling up under the tree and scooped up about 7 gallons worth the other day to make compost from.

Check out this site for plans to build a bat house and go online and search for bat houses.

Last year I was thinking of attracting bats so I started this thread. Got busy and my reading indicated it would not be easy attracting bats - I built bird houses instead.

Early summer and bats - great. I found them in back yard at dusk.

Tonight, I found them exiting the house from the soffits - not so Great.

Now I have to build a bot house to get them to move out of my house - go figure.

Do try to use untreated lumber - old pallets work great as long as you know nothing nasty was stored on them.

Placement in height, free fall clearance, and orientation are the most important factors in getting residents. Check batcon.org to see what the best placement is for your part of the world. They (and Tuttle, love his work) rock!

Tar paper is often preferred over paint (in the short run) as the bats don't like strong smells. Cedar will likewise have a lower success rate until the wood has aged. Try too use an eco friendly paint.

If you use a mesh in the house for traction (and they do like it) be sure it is a rubber mesh NOT metal. Metal mesh can cause injuries.

You can age your house more quickly by turning it upside down in the weather.

If a house remains unoccupied while hanging up, check to be sure uninvited guests haven't moved in (wasps).

The guano is not toxic in itself, it can be harmful to humans in HUGE amounts (like in the caves). The relatively small amount you'll get under a house will not hurt you and makes great fertilizer.

Red bats, hoary bats, and seminole bats are arboreal and will not roost in a house. They will live in a less cleared area than the other bats.

Any water within a mile or so is considered 'nearby' and will help in attracting bats. They will also drink from a bird bath or other similar arrangement. (people with pools will attest to this :)

I definitely think mosquito spraying has some effect on bat populations and it is sad.

madtripper - this is the perfect time for you to find the bats. They should be leaving soon for the winter and you can seal all their entrances while they are gone and put up your houses. When they return for the spring and find their holes closed and a house nearby they should move on in.

I'm so glad to see so many people wanting bats!! :)

HI,

So happy to see such interest...I bought one of those "marketed" bat houses and put on a tree...no bats in the house, but plenty at dusk in my yard...

I'll check outone of the links above, or if anyone could share with me a good link, I'd really like one!

I was quite successful with bat houses till the wild cats got to it. The cats killed them all. So now I don't even bother with them anymore.

Dawn

I have a few biology classes who are interested in putting up bat houses and recording observations over the next few years. We are looking for plans for bat houses and were wondering if the same plans are good for Big Brown Bats and for Little Brown Bats?

I just saw something on television about this. They suggested that size is one of the factors of success. They mentioned that many people build them too small and then the bats don't use them. Because they are social animals, they want them big enough to hold a couple hundred. The one they made was a couple feet tall and a foot and a half across (my estimate). They mentioned they needed to be quite high up for the bats to be able to fly because they are really gliders and need to start up high in order to fly. They also said that you should stain them with dark stain to absorb the sun because they need to stay warm. That is about all I know about them. My dad had a huge colony in our barn when I was a kid. They kind of creeped me out. I know they are good animals to have around, but I haven't gotten the courage to put one up yet.

Our home has a built-in bat house. Bats live in the louvered vents that are near the peak of our two-story home.

Can't remember where, but I read that they need the morning sun to warm up. Come to think of it, our vents are on the east part of the house, so this may be why they stay there. They've been coming here for years. My husband discovered their home when he was painting this area while precariously perched at the top of a very tall ladder. Almost lost him.

We enjoy having them here for the summer for they come out at dusk & help with our mosquito population.

I know that most recommendations suggest that bat houses need to be up high with lots of room underneath so that they can drop down and start flying. Mine lived in the attic and the exit spot was where a horrizontal roof met teh a slanted part of the roof. They had almost zero drop space. They were flying within a foot or so from the opening.

They may like to have this drop zone, but they certainly do not need it.

I built a bat house today. Due to some confusion with the plans, the crevice is 1.75" deep, instead of .75" deep. (I used the 2" side of the 1x2 as a wall; should've used the 1" side.) Will this matter? Will it be too deep for them? I can take it apart tomorrow and turn the 1x2's, if it matters.

I should've done more research first; I've also discovered tonight that the shed where I planned to mount the house, is too short. I guess I'll have to put a post in.

Leslie

we bought a bat house & have yet to hang it (we'll need it after all the rain here in southern maine). in addition to the placement instructions already covered here, we were advised to let a bannana peel spoil to the point of stinking & smear that against the opening of the bat house. Anyone else heard of this method for attracting them?

to Laura zone5
Could you please post your your set of plans to make a bat house, I could not see anything.
Thank you very much

If anyone is reading still I found an interesting article from a University of Florida student here http://edis.ifas.ufl.edu/m/#publication?id=UW290