deep cavities as good as owl guards?

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Posts: 59
Joined: Wed Mar 25, 2009 6:31 pm
Location: kansas/tonganoxie

Hello all, last year I modified my houses to make the cavities 12" deep, I did this thinking it would help stop predation. Are owl guards still a necessity with deep cavities?
Louise Chambers
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Joined: Tue Nov 04, 2003 1:07 pm
Location: Corpus Christi, TX

Deeper cavities are certainly helpful but they won't stop owl predation completely. Adding external guards will add an extra layer of protection to your birds. Some landlords also employ offset entrances and baffled nest trays to increase safety. A combination of some or all of the above are worth using.
check out ideas and photos in this thread: ... ight=ghost


Building a deep cavity house is my new project, and I'm glad you asked this. I'm thinking I will still provide some sort of owl guard, but haven't decided, as of yet, on the specific type I will use. Do you have pix of your house that you wouldn't mind sharing or pm'ing to me?
Last edited by Guest on Mon Apr 27, 2009 2:06 pm, edited 1 time in total.
Emil Pampell-Tx
Posts: 6743
Joined: Tue Nov 11, 2003 1:26 pm
Location: Tx, Richmond (SW of Houston)
Martin Colony History: First started in Gretna, La in 1969 with a small homemade house, have had martins ever since at 2 different homes in Texas

I have considered doing that, but got to thinking about it and decided against it, its too hard to build. My thinking is that they are just as safe in a horizontally deep cavity as they are in a deep vertical cavity. I think that it is easier for them to exit a horizontally deep cavity.

Since many natural gourds and plastics that I use are 9 to 10in in diameter, I simply add a longer tunnel to them, try to make them 13 to 14in horizontally deep. For me, this is the easiest and quickest way. The martins seem to like these long tunnels. I don't think that the martins will flush as quickly in a gourd of house that is horizontally deep, and a gourd that does not swing.

Some people however like the idea of a deep vertical, so good luck.

Owls like to flush the martins, so a deeper cavity may help. I too agree that a wire around a house or a wire cage around gourds is the best way, I just don't like the idea of building a cage around my gourd racks, they are too large already. Maybe the longer tunnels will help.
Posts: 59
Joined: Wed Mar 25, 2009 6:31 pm
Location: kansas/tonganoxie

Louise, I understand that more is better, but I have seen pictures of owl guards fastened to the porches on both sides of houses with 6"by6"cavities, those porches can't be over 3"wide, that means it is only 9" maximum to the back of the box,from the guard. That's why I think it is better to have 12" cavities with no guard, than 6"cavities with an owl guard, or am I not understanding something, which is highly possible!! Thank you.

Liz, I have a hard time typing,and with this internet crap, but I would be glad to give you the dimensions, I just built it as I went, out of plywood I had on hand, but it looks good, or so my wife says, I guarantee she would have told me if it looked like crap. It is also heavy ,I have it mounted on a 6" round pole, but it doesn't sway in the breeze, like my commercial one does. Let me try it to see if they like it first OK? Thank you.

Emil,I must have not made myself clear, these cavities are 12" horizontally, sorry about that. I think you are right about birds exiting horizontal cavities faster than vertical cavities that just makes sense,something about gravity probably! Thank you for the reply.
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