Species specific entrance hole...is this right? (1 Viewer)

[tweezak]

I just started building my own bird houses and nest boxes and as a newbie I'm looking for information on proper hole sizing for different species.

I know we have a lot of finches in the area along with house sparrows, juncos and chickadees. My brother found this list but some of the recommendations seem like they'd allow predators or nest invaders.

http://www.wild-bird-watching.com/Building_Bird_Houses.html

In particular, the 2" hole suggested for house finches seems very large. Is there a danger of house sparrows or cowbirds trying to take over the nest? Also, won't bigger birds find it easy to get to the nest and eat the chicks?

Thanks!

 

[Joe1980]

That is a perfect chart for nestbox building. Follow those guidelines, and you're good to go. However, there's a few things you should know as a beginner. For starters, anywhere you have the presence of house sparrows and starlings, your nestboxes will be taken over by them. Sparrows pretty much take up any house with an entrance hole of 1 3/16" and up, although they will not like a large house like the one for screech owls and flickers. I know this because I built one of those, and the sparrows don't like it. I shooed starlings out once, but never did get anything but squirrels and hornets to nest in it. Starlings will take over any house with around a 2" hole or more. Like I said, if you have house sparrows, forget having anything else nest, unless you go with the small boxes made for wrens and chickadees. These have holes too small for sparrows, so you will be successful, assuming the wrens or chickadees choose to use it. In my experience, house finches don't use nestboxes, but prefer to use spruce or pine trees. I get house finches nesting around my yard in my small spruce trees every year, so if you want house finches nesting in your yard, plant some spruce trees.

 

[tweezak]

Hole saws?

Thanks, Joe.

I'm having some trouble finding hole saws in the sizes I need now. I want a variety in 1/8" increments with an interchangeable arbor. The Milwaukee saws they sell at Home Depot are nice but once you get over 1 1/4" you have to buy a new arbor for $15. If you buy the $50 kit then the arbor comes with an adapter for the larger saws. What a racket.

Anyway, I've only built a few houses so far. My designs are here:

http://sketchup.google.com/3dwarehouse/cldetails?mid=510fb8cd174e23c2197ccd16d2c31a13

Let me know what you think.

Cheers!

 

[Joe1980]

All hole saws have the arbor issue you speak of. I am an electrician, and part of the tool stock on my work truck includes an entire hole saw kit, so I have the luxury of having all sizes up to 6", plus the arbors. You are kind of stuck with buying the kit and/or arbors, unless you go with spade or forstner bits of the specific sizes.

Your plans look good to me also, and make sure you remember to soap or grease up the roofs to prevent hornets and wasps from taking over.

 

[tweezak]

All hole saws have the arbor issue you speak of. I am an electrician, and part of the tool stock on my work truck includes an entire hole saw kit, so I have the luxury of having all sizes up to 6", plus the arbors. You are kind of stuck with buying the kit and/or arbors, unless you go with spade or forstner bits of the specific sizes.

Your plans look good to me also, and make sure you remember to soap or grease up the roofs to prevent hornets and wasps from taking over.

I guess the thing that bugs me is that the kit has an adapter to make the same arbor work for everything but you can't buy the adapter by itself to use with individually purchased hole saws. You have to buy a separate arbor.

As far as the soap or grease, I was reading about that in another thread and am planning on doing that as soon as it stops raining. We've had record rain (along with crazy wind) and my slanted nest box which is facing directly into the weather is still bone dry inside. :t:

Thanks for the info!

 

[etudiant]

Hi Tweezak,
You can use your 1.25" drill to make an oval hole, which is narrower but higher at about 2.25", so you avoid needing a larger bit.
Sparrows are a bit less fond of that also, but it works well for Bluebirds.
Remember to put on a predator guard and hinge one side or the top, so you can clean out the box in the fall.
The Van Ert sparrow trap works well if you have a problem with them.

 

[Joe1980]

Just to put it out there, I tried a house once with the angled hole, but the pesky sparrows didn't mind it at all. Then I built this fancy house with the hole on the bottom, labeled as a "sparrow proof bluebird house". It turned out to be a bluebird proof sparrow house. But, I've come to the realization that I have no bluebirds around, so it's a lost cause.

 

[tweezak]

Hi Tweezak,
You can use your 1.25" drill to make an oval hole, which is narrower but higher at about 2.25", so you avoid needing a larger bit.
Sparrows are a bit less fond of that also, but it works well for Bluebirds.
Remember to put on a predator guard and hinge one side or the top, so you can clean out the box in the fall.
The Van Ert sparrow trap works well if you have a problem with them.

By "predator guard" do you mean an additional piece of wood that makes the hole twice as deep? I'll look into doing that.

All of my boxes so far have a hinged bottom and a latch. If I start doing a lot of them I will probably change my design to cut down on costs as hinges and latches come to about $3.

I may have found a solution to my drill problem. I got an "atta boy" at work today part of which was in the form of a $25 Home Depot gift card. Now I can buy that hole saw set with a clear conscience. ||

 

[etudiant]

Hi tweezak,
Congratulations & "atta boy"! The birds will thank you.
Predator guard is exactly as you say. It helps keep larger birds from sticking their head in to peck at the nestlings and also makes it harder for raccoons to raid the nest.
Hinge is better on the top or the side, that way you can do a quick inspection w/o disturbing the nest. If on top, a scrap of leather can serve as the hinge, or you can make one side of the top removable.
A dental mirror through the nest hole will serve at a pinch to inspect the nest if the hinge is on the bottom..

 

[tweezak]

Hi tweezak,
Congratulations & "atta boy"! The birds will thank you.
Predator guard is exactly as you say. It helps keep larger birds from sticking their head in to peck at the nestlings and also makes it harder for raccoons to raid the nest.
Hinge is better on the top or the side, that way you can do a quick inspection w/o disturbing the nest. If on top, a scrap of leather can serve as the hinge, or you can make one side of the top removable.
A dental mirror through the nest hole will serve at a pinch to inspect the nest if the hinge is on the bottom..

Thanks.

I was always taught (probably mistakenly) that if people disturbed a bird's nest there was a chance it would abandon it. Is this not so? I'd hate to unwittingly kill hatchlings just because I was curious.

 

[etudiant]

Thanks.

I was always taught (probably mistakenly) that if people disturbed a bird's nest there was a chance it would abandon it. Is this not so? I'd hate to unwittingly kill hatchlings just because I was curious.

Have not found that to be the case, for Bluebirds , Tree Swallows or Wrens, at least after eggs are laid.
However, before they settle in, disturbances can cause them to move, so it better to not bug them while nest building..
Unfortunately, House Sparrows will kill existing nestlings and their mother if needed during a nestbox takeover, so just letting things go for the season is no solution either.

 

[tweezak]

Bought this today. With my various gift cards I paid $21.:t:

http://www.homedepot.com/webapp/wcs...logId=10053&R=202327772&catEntryId=202327772#

Now can anyone explain to me why it seems that every hole saw set seems to skip over 1 1/4"? The one I bought steps in 1/8" increments from 7/8" to 1 3/8" with the exception of 1 1/4". If I want that size I'll have to spend another $8. :C

Whatever...I'm ready to make some houses with holes.

 

[Joe1980]

They skip that size because it's the one you need!