Bat House Forum

[cloudman75]

Today it is around 97 degrees and the bats are having a hard time finding a cooler spot. I went out and took a look and they were down at the bottom entrance after lunch. I took a photo of them to post. it is not very clear but you can see a bat or so.
One house is light blue, the other unpainted cedar. If they were darker, I think the bats would leave for a cooler roost. A color chart I viewed called for medium
colors the same as for states all the way up to the border with Canada. The chart is based on high July temperatures. Low temps are ignored. Last night at midnight
here in the Atlanta area it was 85 degrees, while in northern Montana it was 69 degrees. Just my opinion but bat houses in the south should be a lighter color if painted .
Temps of 69 degrees at night could use a boost from a darker color, I don't agree that they need a boost from 85.
With their body heat and some sun exposure, the house is probably in the 90s here by 10 AM on many days in July & Aug.
There are exceptions depending on species. The freetails seem to tolerate higher temps than the little browns, but also lower temps as some were here last winter for a short visit. None of us have all the answers, but can have opinions. The bats make the final choices.

[Terry Lobdell]

Frank, I have done a lot of experimenting with different ways to vent a bat box because my big browns here in NWPA can't tolerate high temps.

My boxes with the access slot/vent in back are heavily used by the big browns. I have some pictures posted on here. They love the open top behind the box on hot days.

I am going to start doing this on some of my pole mounted boxes as well.

Another thing about having the back crevice with an open top is some bats will actually exit out of the top giving them a higher exit flight starting point.

I have a chimney box of this style and my big browns use it intermittently throughout the season.

As far as color goes, I think the right design with plenty of venting and a box with lots of mass is probably more important than color. But obviously some colors such as flat black in the south or white here in the north will not work.

Literature says that I should have all my boxes be flat black in this area. However the past couple years I have been staining and painting my boxes a chocolate brown. I think it is more asthetically pleasing and I feel this color gets the boxes plenty warm enough.

I think a heavily box built of one and two inch wood with at least 3 to 5 crevices is ideal to hold night time temps.

LIttle browns achieve their desired warmth much from roosting in large numbers anyways.........