Bat House Forum

[Nbraman]

I am looking for your help in building and placing of 20-50 bat houses in parks around Minneapolis Minnesota.

My Boy Scout Troop #446 will be building and installing these bat houses. I need advice about:

Preferred bat house designs

Plan and specifications to build the bat houses

How should the bat houses be mounted?

What are the best and worst places for the bat houses?

Is there a specific area that the bat houses need to be in, such as in an open field or at the edge of a forest? Can they be in or near water?

What materials should and should not be used for bat houses?

How much human activity will bats tolerate?

Are there any grants available to help me with the costs of these bat houses?

Do you know of anyone that would donate a bat house for my Eagle Project?

Thanks for your help,

Sincerely,

Nathan Braman

You can contact me at
acorn@iaxs.net

952-888-4901

8040 Stevens Ave. S.
Bloomington, MN 55420

[Joe Spencer]

Hi Nathan, Welcome and yes mounting/erecting bat houses next to water is highly advantageous. Regarding grants you could wait for Mark Kiser to reply about that here at some point. I highly recommend that you get the Bat House Builder's Handbook. It is an easy read yet amazingly informative. Most of your questions are certainly answered within the book. It is $7.95 non BCI members and $5.95 for BCI members.

AND


Find them HERE (scroll down): http://www.batcon.org/catalog/bathouses.html

Looking forward to your project updates! Joe.....

[Mark Kiser]

Hi Nathan,

You have quite an ambitious project! The best designs are nursery- and rocket-style houses. Nursery houses are typically 30 inches to 36 inches tall x 16 to 24 inches wide x 4 to 6 inches deep, depending on how many chambers there are. Chamber spacing should be 3/4 inch to 1 inch. Most nursery houses available for sale have 3 to 5, some have 7.
Nursery designs can be wall-mounted or pole-mounted. Nursery house plans are available in The Bat House Builder's Handbook in BCI's catalog as Joe mentioned above. A sawing diagram for a 5-chamber house is located at www.batcon.org/bhra in the newsletter archives section; see the Fall 2002 issue.

Rocket designs are best suited for pole-mounting, but they can be adapted for buildings. These are 3-foot tall or taller narrow boxes that allow bats to move in a 360 degree circle (or square) to find warm or cool locations, depending on their preference. Joe has plans posted for his 3-chamber Mega-Rocket box on this site. Plans for a 2-chamber rocket box can be found at www.wildaboutgardening.org. Plans for the original Dourson and MacGregor 1-chamber rocket box can be found at www.batsnorthwest.org, although this set and the 2-chamber design above have been modified for northern climates. Vent slots or holes are recommended on two opposing sides 12 inches up from the bottom on the outer shell.

To build so many houses, you might want to stick with the one-chamber rocket box. Otherwise you will not be able to afford the materials. Many types of dimensional lumber work well, like western red cedar, white cedar, poplar, etc. Exterior grade plywood such as AC, BC, or T1-11 work well for nursery house fronts, backs, and internal dividers. Fiber-cement board is another possibility although you need special tools to cut it and it can be heavy.

Mount your houses out in the open in sunny locations or about 25 feet from the nearest treeline. It helps immenselyl to have a permanent water source within 1/4 mile. The bottom of each box should be 12 feet high or higher. Steel poles last the longest. Pole mounting tips are available at www.batcon.org/bhra in the Fall 2000 issue of The Bat House Researcher newsletter, see the archives section.

Don't make small boxes that are the size of bluebird boxes except it's ok to make a few as decoy boxes to attract wasps (Thanks Kent for this tip!)

Dont' mount your boxes on trees. Don't mount them where they will interfere with other activities, and on buildings, don't put them above windows, doors, or high-traffic areas.

Bat houses should also be mounted in a place where someone will monitor them and take care of them in the future. Just installing bat houses and leaving them will ultimately not do bats any favors. The houses will need periodic repainting and recaulking, not to mention cleaning out wasp nests in the off season or whenever bats are not present. A wooden bat house will probably last only about 10 years at best before it needs replacing.
Bat houses that fall into disrepair will be abandoned.

Theoretically you could mount them in water, but this would cause many logisitical problems and it will be difficult to maintain and inspect the houses. Best to stick with dry land.

Hope this helps. BCI is not able to help with funding for these types of projects, but home centers or hardware stores are good places to look for donated materials. One Eagle Scout candiate in Austin that we advised built 8, 4-chamber nursery houses with his troop, these were installed on abandoned utility poles. Building and installing 8 houses were enough to fulfill his 100 hour service requirement. He obtained free or discounted plywood, lumber, and "oops" paint at a home center, and a local grocery store and a pizza place dontated food and drinks for the troop while building the houses.

Best of luck with your project and thanks for your efforts to help bats.

Sincerely,

Mark Kiser
Coordinator, Bat House Project
BCI