Well, Lisa of Michigan says that downies use her nestboxes through the winter as shelter. I have winterized mine in the hopes that they will be used that way.

I don't know enough about the "nesting now" possibility. It would seem like not an instinctive thing to do this time of year.

Good luck and enjoy observing!

Chickadee -

What do you do to "winterize" them? Just clean out any nesting litter?

- Jim

Well, yes, first I cleaned out any nesting litter that was in the nestbox.

Then I took what I happened to have on hand - some very solid packing styrofoam pieces - and pressed them tightly into the upper and lower ventilation cracks so that they would stay there and keep cold air from coming in, and heat from going out. Then I put grass clippings, in a layer about 1-2", in the bottom of the nestbox.

I also read that you could put a layer of styrofoam, or woodchips, on the bottom of the nestbox for insulation.

No doubt you could use something you have on hand to block the ventilation cracks. The weatherstripping you use on doors/windows (which is what I would have used if I had been able to locate it in our garage!) would be ideal.
Anything that will stay put all winter, and that you could then use a screwdriver, whatever, to take out in the spring for the ventilation the birds need when it gets warmer.

Also, I guess it is best, if you can, to put your nestbox up so that the prevailing winds are not coming right at the entrance. I've tried to put mine up with their backs facing west, against the weather.

I also put up a large winter roosting box this fall, and I did notice, that it was built with the top sealed tight,and there are no cracks for cold air to get in. Also, the entrance is at the bottom of the front, so that warm air will rise and hopefully stay in the box.

Hope this is helpful -

Chickadee, thanks for sharing -- you have a lot of good ideas there.

I recently designed and built a cold frame (about 3 by 4 feet, and 1 foot high) for starting plants from seed next year, and I was thinking that during the winter I could prop it open about two inches, and allow birds to use it for a shelter. With a clear plastic top and black interior, it should capture some heat from the sun even in winter. I'm hoping that birds will share it. Perhaps I should provide it with loose leaves for warmth, a tree branch for perching, etc. Anyone have any suggestions? Would it be safe for the birds, being close to the ground?

For a description of the cold frame, see my blog

- Jim

Hi Jim,

What a cool cold frame. You must be one dedicated gardener.

I gave some thought to your idea of using the cold frame for a bird shelter.

Birds certainly could go in the cold frame like that - I am just wondering whether other things would too, it being on the ground, as you wondered. Maybe you could place the cold frame on something higher up, and not too far from a bird feeder, so the birds will notice it.

Also, I was thinking that since you build things, maybe you could somehow cover the space of the propped up sides and front of the cold frame with some light plywood that you could nail on temporarily, leaving an opening for an entrance. This would prevent snow from drifting in, keep the warm air in, and make it look more like a tree surface/nestbox.

Your idea of branches for perches is great.

I'd give it a try! No doubt colder weather is not far down the road - Good luck!

All 5 of my nestboxes have Downies roosting in them. I just duct tape the cracks and add some wood shavings to the bottom.You can put hole guards on so they wont alter the size but the downies need 1&1/2 inches to get in. They are roosting not nesting at this time of year. We grew birdhouse gourds last year. I have about 8 that we dried, put a couple cotes of poly on, put some wood shavings in the bottom and hung in protected trees. I have Downies in them too. James, please go to the www.sialis.org website to learn why your boxes are not safe and also why you may want to think twice before encouraging House Wrens to nest on your property.

Be sure to put in predator guards, baffles, etc., or your winter roost box could turn into a lunch box for a hungry predator

I thought I had a house wren in one of my new nestboxes this year (one built with specs for chickadees - a 1-1/4" entrance). I panicked, thinking my new bird habitat was going to be turned upside down by a nasty house wren. But she turned out to be a lovely Carolina wren, who had a nest and was around all summer. She has a lovely song and has been a pleasure to have around.

Thanks for the reminder - I did put a "toothbender" on the entrance to our winter roost box - 1-1/2" in diameter (large enough for downies but no larger)- but honestly, the perches in this one are so far above the entrance (this thing is so big,it's like a Red Roost Inn), which is at the very bottom of the front, that no paw/arm/leg could possibly reach an unsuspecting bird. I did still mount it up in a tree, however.

Thinking further about it, I don't need to prop open the cold frame, which would make a 4-foot long narrow opening. I have two ventilation holes (2 by 4 inches) in the back wall, blocked by hardware cloth and 16 inches above the ground. All I need to do is remove the hardware cloth, then install hole reducers to reduce the holes to 2 by 2 inches each. Each hole reducer can also support a shelf/perch INSIDE the box, which will allow the birds to check the interior after entering. The inner shelf will also restrict the downward reach of any predator paws. The box is so big, though, that birds can easily stay out of reach of any predator paws.

I thought of putting the cold frame up on the railing of the rear deck, where in a corner position, the railing would support three corners of the frame, needing only one temporary leg for the last corner -- but my wife vetoed that idea (too unsightly). (It was designed to be portable, in three stackable sections of about 30 pounds each, with a hardware cloth plus porous plastic bottom.)

We have no snakes of any kind in this suburban area. Rats and mice are under control, because since I have been killing them, there are no more signs of them trying to tunnel into my shop/storage area, which has a dirt floor. But just in case, I can add a smooth hard material to the back wall of the cold frame so that rodents cannot climb up to the entrance holes.

The other possible predators are wandering cats (common) and racoons (rare). The inner shelf/baffle will stop them.

I have st least a dozen small plastic pots that I can lay sideways in the cold frame in case some birds would like to roost in them. A bed of leaves and perching branches are the other options to offer.

As for the 'wren' nestbox, the downy has enlarged the opening to 1 1/4 inches. I cleaned out old twigs and put a pile of sawdust in the bottom.