Oval opening for nestboxes (1 Viewer)

I know from internet articles that some birds will enter through a wide but shallow opening, and such a strategy helps keep nestboxes free of House Sparrows.

For several months, through the fall and now into January, I'm experimenting with slightly oval openings on four of my nextboxes in my New Jersey suburban backyard. The intention is to keep out house sparrows. In one, attached to a wooden pole under a holly tree, a female downy woodpecker ducks in to sleep every night. The nestbox little downy uses has a wooden predator guard attached, along with a copper hole protector / copper portal. The copper protector is attached so that part of it overhangs the top of the opening and leaves part of the wood hole exposed at the bottom. Overall height of the opening is reduced by about 3 mm to around 33 mm (about 1 1/4") while the width remains at 36 mm (about 1 1/2").

I don't see any evidence of any of the other nestboxes being used for sleeping.

Has anyone experimented with oval openings (or round openings with a straight piece reducing the overall height) for nestboxes intended for chickadees, nuthatches, wrens, titmice or downy woodpeckers?

House Sparrows are a problem in my patch; they're invasive, predatory, and damaging to property. I can tell you stories on all three of these areas but I suspect we each have similar experiences. Because of their numbers, I pulled my feeders years ago. This past fall I pulled my bird baths for the same reason, I don't know what I'm going to do come spring and summer.

Last summer I experimented with exactly what you described; changing the opening to 1-1/4 inch from 1-1/2 inch. You're metal plate is nice, I ripped a 1-by and tacked it over the top of the opening. The female could squish her way in but the male was too big.

Their numbers cause them to be desperate; there's only so many nooks and crannies thus the damage to soffits and other structures.

Most of my boxes are for Bewick's Wrens, I have occasional Rock and House Wrens but never had them build a nest in a box. So, my openings are 1-1/8. The Bewick's have built box nests but never used them; the House Sparrows harass them until they flee. I've found Bewick's nest in crevices on my house, with eggs, but that only occurred once. This year I'm putting up more wren boxes, I'm hoping for better results.

Other than House Sparrows, I've had no other birds using the boxes for roosting. Not even the House Finch compete with the House Sparrows for boxes, they don't even try, I imagine the predatory nature of the House Sparrows keep them away.

No chickadees, nuthaches, titmice, or downy's (that I've seen) in my patch/house.

The attached photo is a shot of a chickadee hole, I watched the birds work the opening until they were able to get inside the stump. I saw the last 4 days of their work, I imagine they were at it a lot longer. The location is northern Wisconsin near the upper peninsula this past summer. The shape of this opening is something you might consider trying.

I'd be interested in knowing how your boxes pan out this spring and summer.

Good Luck my friend.

That's interesting seeing the shape of the chickadee hole.

SanAngelo said:

House Sparrows are a problem in my patch; they're invasive, predatory, and damaging to property. I can tell you stories on all three of these areas but I suspect we each have similar experiences. Because of their numbers, I pulled my feeders years ago. This past fall I pulled my bird baths for the same reason, I don't know what I'm going to do come spring and summer.

Last summer I experimented with exactly what you described; changing the opening to 1-1/4 inch from 1-1/2 inch. You're metal plate is nice, I ripped a 1-by and tacked it over the top of the opening. The female could squish her way in but the male was too big.

Their numbers cause them to be desperate; there's only so many nooks and crannies thus the damage to soffits and other structures.

Most of my boxes are for Bewick's Wrens, I have occasional Rock and House Wrens but never had them build a nest in a box. So, my openings are 1-1/8. The Bewick's have built box nests but never used them; the House Sparrows harass them until they flee. I've found Bewick's nest in crevices on my house, with eggs, but that only occurred once. This year I'm putting up more wren boxes, I'm hoping for better results.

Other than House Sparrows, I've had no other birds using the boxes for roosting. Not even the House Finch compete with the House Sparrows for boxes, they don't even try, I imagine the predatory nature of the House Sparrows keep them away.

No chickadees, nuthaches, titmice, or downy's (that I've seen) in my patch/house.

The attached photo is a shot of a chickadee hole, I watched the birds work the opening until they were able to get inside the stump. I saw the last 4 days of their work, I imagine they were at it a lot longer. The location is northern Wisconsin near the upper peninsula this past summer. The shape of this opening is something you might consider trying.

I'd be interested in knowing how your boxes pan out this spring and summer.

Good Luck my friend.

Click to expand...

You are one of the few people I've heard that have had a Bewick's Wren build a nest in he nextbox! I have only had this happen 3 times over the course of 10 years, but the female Bewick's apparently has rejected my boxes each time.

Have you ever noted the House Wren pestering your Bewick's Wren?

Sorry for the hijacking of the thread, it is just so neat you have a potential Bewick's Wren, they are a species in decline.

Contendedbirder, I wish you all the best with your nextboxes this spring! I keep my boxes sized at 1 1/4, but have never experiemented with the shape of the hole. I usually get either Black-capped or Chiestnut-backed Chickadees, but once I had Red-breasted Nuthatch and 3 times a Bewick's Wren made a nest, but they did not actually use it for nesting :-( Let us know what happens!

I used Van Ert traps to discourage the sparrows high jacking nest boxes in CT, but if you have lots of them, that won't work.
There are claims that hanging strings near the nest box discourages House Sparrows, apparently they are not as agile in the air, but its only hearsay, no personal experience.
House Wrens are bad neighbors, they pierce the eggs of birds nesting nearby, so give them plenty of space, their cheerful song is such a reward.
No Bewick's Wren here in the North East, you are so lucky to get this little jewel to nest, hope it works out very successfully.

DownyWP said:

You are one of the few people I've heard that have had a Bewick's Wren build a nest in he nesxtbox! I have only had this happen 3 times over the course of 10 years, but the female Bewick's apparently has rejected my boxes each time.

Have you ever noted the House Wren pestering your Bewick's Wren?

Sorry for the hijacking of the thread, it is just so neat you have a potential Bewick's Wren, they are a species in decline.

Click to expand...

My Bewick's Wrens completed their nest building in one of my 9 houses earlier this week. The male did most of the building but towards the end he had his mate helping out. She wasn't nesting just finishing up the construction.

Three days ago, I go outside and find a male House Sparrow sticking his head in the box hole pulling out the nesting material, he couldn't get his whole body in. I stood there watching him as he pulled the stringy material outside the hole. It was a mixture of string, lint, cotton, leaves, and fine dried grass. The material was hanging out and down below the hole, blowing in the breeze.

After a moment or two the House Sparrow noticed me and flew off but came right back when the I didn't make a move to disturb him. I took one step off the deck and he flew off for good. Within a second or two both male and female wrens show up at the box, beaks full of lint or cotton for the nest. They settled on the roof and eyed the damage but never made a move to enter the box. About a minute later they both flew off and haven't returned to that box.

This afternoon I spotted the male with a beak full of nesting material but I don't know which box he's going to. Not all my boxes are visible, some are hid behind a shed.

I've been hearing him call for his mate in the early morning and later in the day but I haven't seen her since the House Sparrow invasion. This is the same thing that happen last year, his mate never did come back after a similar event. I listened to his song all through the summer. It broke my heart.

etudiant said:

I used Van Ert traps to discourage the sparrows high jacking nest boxes in CT, but if you have lots of them, that won't work.
There are claims that hanging strings near the nest box discourages House Sparrows, apparently they are not as agile in the air, but its only hearsay, no personal experience.
House Wrens are bad neighbors, they pierce the eggs of birds nesting nearby, so give them plenty of space, their cheerful song is such a reward.
No Bewick's Wren here in the North East, you are so lucky to get this little jewel to nest, hope it works out very successfully.

Click to expand...

I haven't tried the Van Ert's, I have used the DRST with some degree of success. It's put up now because of all the other bird traffic. Today I had a Curved-billed Thrasher eyeing my deck roof stanchions/beam openings but it was too close to my window and he moved one. I don't have House Wrens. Cactus Wrens come through as do Rock Wrens but it's been a while for them, I think it's because I changed the terrain.

Late addition.....forgot I had this after-the-fact photo showing all the telltale signs of a House Sparrow invasion. The hole looks big but it's only an inch and quarter.

SanAngelo, I am sorry the HOSP interferred with the Bewick's pair; I am hoping they will select one of your other boxes, fingers crossed. Have you ever tried the Sparrow Spooker:
http://www.sialis.org/sparrowspooker.htm

Also, I take down all my feeders during nest season.

Lucky you to have Rock Wren and Cactus Wren, I don't have a Cactus Wren on my life list as of yet.

Etudiant, do you have the Carolina Wren nesting in your area?

Not long after my previous post, about an hour before sunset, I was closing up shop and noticed both male and female wrens along my fence line. First time in three days I've seen the female. When the female saw me she ducked for cover but the male hung around, he's use to me coming and going.

After grabbing my camera, hoping to shot the male skirting along the runners, I was pleasantly surprise to see him checking out the boxes.

The male checked out three of the boxes, going back to the light brown box twice. I gave him space and went in the house, shortly after the female appeared and the male led her around to the boxes.

You can see how the hole has been altered on the light brown house. Staying with contentedbirder's OP, I shrunk the opening by attaching popsicle sticks on the top and bottom of the hole. The height is 1 inch and the width is 1 and 3/8 of an inch, a little larger than I'd like but I'm going with it for now.

On the skinny blue bird box you'll notice I plugged one hole and made another. The hole I plugged made the depth of the box too deep for the wren. I find their nest built up in front of the hole and up to the edge. The back of the nest tappers off down to a thin layer of material at bottom rear.

All my hole openings are 1 and 1 quarter inch in diameter or less, they're all wren boxes.

I move the boxes around if they're not attracting wrens. What I noticed is; they do not like the box if it's in the sun and they like a nice flyway to and from the box.

DownyWP said:

SanAngelo, ..... Have you ever tried the Sparrow Spooker:
http://www.sialis.org/sparrowspooker.htm
Also, I take down all my feeders during nest season. .....

Click to expand...

I've thought about those sparrowspooker......if things don't go good this spring I might pick a box and try one out. I'm hesitant cuz I don't know if they'll spook the wren, I'd hate for that to happen.

I stopped feeding the birds years and years ago, due to the sparrows. I also pulled my birdbaths at the end of last summer. The Kingbirds and Orioles are due back next month, they like the water so I don't know what I'm going to do.

The hummingbird birds are due back in a week or so. Their feeders go up next week.