It depends on what type/size your birdhouse is if it would be suitable for other birds. Some of the wren houses are awfully small for a Tree Swallow or Bluebird to nest in. Bluebirds need a 1.5 inch hole, swallows prefer that too but can get in a smaller hole. Chickadees also prefer the 1.5 inch hole but can get in a 1 1/8 inch hole. A housewren will enter any size hole, not much deters them except keeping the nestboxes far away from brush and trees. House Sparrows can enter a 1 1/4 or larger hole, you would want to keep them from nesting in your birdhouse. A properly mounted nestbox is mounted on a slick metal pole with a predator baffle and at least 15-30 feet away from trees/fences/brush with no branches hanging over the box. Squirrels and or raccoons can and will get into nestboxes placed in/on trees or mounted on wooden posts.

A metal plate on the front is to prevent woodpeckers from enlarging the hole. If the nestbox is mounted properly squirrels shouldn't be able to get to it to chew the opening.

Here is a link to "lots" of info about cavity nesting birds..it is a bluebird site but has load of info about all cavity nesting birds and how to attract them and properly put up nestboxes for them....

Donna

Here is a link that might be useful: Cavity nesting bird info.....sialis...

Thanks for the website, lots of good information there.

Unfortunately, I live on 1/8 acre in the city, a very small yard, I have no desire nor the room to mount a pole in my tiny yard, and 15-30 feet from any trees or brush is in my neighbors yard. With that said, I have no where else to mount the birdhouse besides the tree, or do I just chuck it altogether? Otherwise, the tree is where it will go. The ideal mounting suggestions aren't viable options for me, unfortunately, so I have to make do with what I have available to me.

I'm now totally confused as to how I should proceed. If I don't want House Sparrows, and I don't want Wrens, and wrens nest with 1" opening but House sparrows can enter 1 1/4" opening, what are my other options or suggestions?

Honesty, I have "little brown birds" that visit my feeders daily. I have no idea what type of birds they are, whether they are wrens or sparrows or otherwise. We have cardinals, finches, and hummingbirds (summer), Coopers hawks in the mature maples up front (city trees) of which I am able to identify, and maybe a woodpecker that I've seen or heard. Other than that, I am not familiar with identifications.

Also, looks like I don't want to use a portal protector, according to what I'm reading, until the first egg.

What to do?

woodpecker houses we nail to the trunk of a tree fairly high up in the tree. Bluebirds houses i always mounted under the eaves of the house or barn away from trees or the front door. other bird house i hung on the side of a tree trunk with a homemade hanger like a shelf hanger. or i used eye hooks and a chain to hang from a branch. the jays here nest in the oak brush and i strapped a box to the bigger limb.

I would not put up a box in your situation. Consider feeding Black Oil Sunflower seeds and Niger Thistle(pronounced Nyger)and some peanut buter suit, add a bird bath and you should have plenty of hours enjoying your birds.

I bought a cool birdhouse at the Buck Store...for four bucks? Anyway, I it was made of cheapie balsa wood, so I drilled tiny holes in two spots on either side near the top of the peak, so I could feed a wire through and hang it up...thing is,I don't ever see anything going on any time, no bird crap, no action...I think my dog Max scares any potential squatters away. I'm thinking of relocating the bird house to another, hopefully better location...in a tree beside the quiet side of the house with no windows on that side. Thing is too, squirrels, little fukers, I love critters, but if you're eating little bird embryos, I'm sorry, but squirrel leg paté might be on the menú. lol JUST KIDDING any animal lovers/anti-animal cruelty folks.