Bat House Forum

[Mulligan]

Hi folks,

I run a mini golf course in Massachusetts. About 3 years ago I built a 5 chamber house, fairly large, from plans I found on the net (forgot which website, might have been this one).

I have yet to attract any bats to it.

It's on the south facing side of the building, and gets sun all day long. It's about 15' up, away from most of the pedestrian traffic we have at the course. It does face the parking lot, and there are lights there for part of the night. It's painted dark brown, the same as the building. We occasionally get wasps in there, and I try to clean it out (with a stick or water, no sprays).

Funny thing is, on the direct opposite side of the building, near the entrance to an arcade, we have a small sign. For 2 years we've had a resident bat set up home behind that sign. It's a lot more noisy, bright, and busy there.

Anyone have any suggestions how I can attact bats to the house?

Thanks,

Mulligan

[BatMan]

Hi Mulligan,

Welcome to the site. If you have a bat on the other side of the building utilizing a sign for a roost, I would try building a small 1-2 chambered house and put it up beside the sign.

Bats are very picky, there must be a reason he's using that side of the building. I understand it's on the side of the building that gets a lot of foot traffic, so I would guess you don't want a big-giant bat house on that side of the building.

They say once bats start to use bat houses they will more readily accept and seek out other bat houses.

Peak it's interest with one bat house and maybe it will find the other.

[Joe Spencer]

I have some questions for you:

1. How bright is the evening light which shines on the unoccupied bat house?

2. IF any, how bright is the evening light which shines on the occupied sign on the north side of the building where the bat resides in the sign?

3. Have you collected or do you have any droppings (guano) from the bat which took up residence in the sign?  IF you don't it would be helpful to collect droppings this season.

4. What are your crevice widths?  If they exceed 3/4" they're far more likely to welcome paper wasp nests in the interior.

5. Are your wasp nests at the bottom of the baffles or up inside attached to the roof?  IF they're at the bottom of the baffles and the baffles are level with each other, you should stagger the baffle height which helps to discourage wasp nest building.  Only if they're paper wasp nests.  Mud wasps are a different matter.
 

Food for thought:  Bat houses which are painted dark and face South, are often routinely rejected by Big Brown Bats when temperatures exceed 95 degrees F.  Big Brown Bat bachelor colonies (males) are comprised of one to a few # bats and like cooler locations.  Myotis L. (little brown bats) do like it hotter and have a higher heat tolerance than eptesicus fuscus but attracting myotis is far more difficult within city locales than country locales.  There's a good possibility your tenant is a big brown bat. 

Since you're in my state of MA I can help you by knowing more about your location and other factors as well.  Should you desire, you may PM me in privacy confidence to better assist you or we'll do our best here with your posting feedback.

Cheers, Joe

 

[KC5TPA]

I have a similar situation as my houses are mounted in a north/south fashion and the one in my video that was obviously occupied is the north facing house. The south facing house was completely uninhabited. Same place, same sun, different entrance direction. I couldn’t figure this out until one night I watched them ‘coming back’ and witnessed just how much ‘runway’ they need to swoop into the opening of the house. The south facing house does not offer the same ‘swoop distance’ as does the north facing house so I moved it around to a westerly location do mainly to constraint of my post. I have yet to see if this is beneficial since I am bat-less at the moment.

 

Before: http://www.youtube.com/watch?v=rR_F09nP9I4

After: http://www.youtube.com/watch?v=GnfUQaZ-Jls

You can see the way I moved the house around trying to promote its use, but it did not work. In fact it may have scared them off, but I don't think they would have used the other house 4 more days and then decide to bail. The day they disappeared was the first slightly warm day so I think they continued their journey, that is what I'm hoping anyway. In fact that night I moved it I had my record number so far, but then we had a very bad storm and the numbers never recovered, and then 'bloop' they were gone.

In saying all this I should have started my own Q&A, but I was just pointing out the same occurences you have, which is in direct contrast with most of the info out there for 'attracting' bats with house placement and design.

[Joe Spencer]

Welcome KC and thanks for the informative post and video.  I counted close to 70 bats emerging from the northern house in that video. Now that you have changed moved the southern faced bat house 90 degrees does it not allow more solar afternoon exposure on the back/rear of the northern house?  I couldn't tell if your bat houses are painted.  If they are what color are they?  Thanks again and looking forward to your future insight and feedback.

[KC5TPA]

Actually the move of the house has cut the exposure. Before the houses were level with each other and the north house received a healthy dose of exposure, so you know what you may have a good point. I moved the south house one night after they emerged so I didn't have a whole lot of time to really mount it like I wanted. I thought about the mounting and temperature, but I may have thought wrong.

If I don't have any occupants by midweek I'm going to take down the west facing house, and do something with it, so the north house gets at least the exposure it was before. Right now, one half of the north house is getting exposure, because it is blocked by the now higher and perpendicular mounted west house. I need to clean it up and re-seal it anyway, both of them actually.

There is no color just a clear coat finish; it gets pretty hot here in the summer. I imagine we will see an easy high 90s summer. I wish I knew exactly what my situation was with the almost 50% occupancy one day to zero the next and still this way for over a week.

I thought that I might have been sabotaged with some kind of spray and something, so after a few days of no shows, I sprayed out the inside with the water hose, but I am still without tenants.

Anyone have any ideas?

 

[BatMan]

My parents rocket house was occupied by a max of 27 bats during the winter and it seems as soon as it started warming up they took off. I'm thinking they were migratory bats that will probably be back in the fall. I could be wrong, only time will tell. Maybe you have the same situation.

[KC5TPA]

I guess that would be ok, but I hope not. I see others flying around in the area but none are liking my houses now, I just don't get it.

[Joe Spencer]

Last summer I had large colony of Big Brown bats use two of the bat houses on my house and then woosh they were gone and did not return to those houses.

[KC5TPA]

So what are you telling me?? :? Please, don't tell me I have to wait until next year? I've waited a year already.

[BatMan]

Trust me I know how frustrating it can be. We've spent a lot of time building houses and I've only had that one rocket at my parents be utilized. I have 3 houses that have been up for almost 2 years now and have never been used but it is fun to try different houses (designs and colors) I guess if my houses ever get used I'll be that much more appreciative.

[Joe Spencer]

JUst info really without drawing any conclusions or assumptions since I also had a rocket bat house 20 ft. away which was occupied by a smaller # of bats for most of the spring-summer season at the same time as my brief visit in my other houses.  It was strange though to have so many of them for such a brief period of time not unlike you.   I would remain optimistic since you had them once, your likely to see activity in the future.  Your experience with the brief stay is etched in your mind and ours and provides invaluable data and feedback on their habits and behavior. :cool: 

[KC5TPA]

Well, as you can imagine my intent for wanting them initially was for the most obvious reason, BUGS. If they (bats) are not going to help me out, I'll have to employ the only other method other than bug spray which would be a zapper. I have just moments ago, being a desperate man employed what I hope will be the fabled 'bat attractant.'

Has anyone installed a bug light, or bug zapper, close to a bat house in hopes of them locating the food and thus the house??

I'm sure I'm not the first to think of or this this, but as I said I am a desperate man. I hope to have another house up by this coming weekend, so I hope to have more to report then.

 

 

[Joe Spencer]

You would need more than one bug zapper's light or (at least a large one) to attract the amount of light which would attract substantial amounts of insects to attract bats.  Sounds like it is worth trying since experimenting is what this is all about. Do a search on "Rangers" on our forum search box and you will see my info about bats  and lights-insects at where the Texas Rangers play.  Googling it afterward may provide some more info.  What I can tell you is that insects are drawn to white lights (like mercury vapor) which are slowly being phased out somewhat due to environmental concerns and they're not attracted to the sodium lights which are more orange/yellow in color.  I meant to ask you HOW FAR ARE YOU from a YEAR ROUND WATER SOURCE such as a LAKE, PONd, RIVER, etc.

[KC5TPA]

I watched for a little bit, and there were a few coming around, I was about 20 to 25 feet away from the light, and could smell the little 'zapped' critters, so this may not be a good idea for the purpose in mind. I wouldn't think the bats would appreciate the smell, but then again it may be like blood in water.

All I can do is look for evidence in the morning, if I have a pile of dead bugs, or a pile of feces(dead bugs) I'll be happy. But I sure wish it would be the latter.