Very sorry for your loss terrene. Bluebirds are natural cavity nesters and will sometimes choose a dead tree or stump hollow, but there's little you can do to make such a nest-site safe.

You might use the tragedy of this failed nesting to encourage your male to bring his new mate to your safe nestbox (if you can provide him one).

Best luck to you and your Blues,

Kenn

Put up a nest box so you can protect them : ) You may even get another nesting if you put one up quickly. He may not re nest where there has been a failed nest. The instructions and tons of info are here www.sialis.org Good Luck!

Thanks for the replies! The thing is, there HAS been a nestbox available both years. Last year it was on a pole (and I've got an extra baffle for the pole if necessary), and this year I've used it as a HOSP trap and mounted it on the house and then on a tree. The blues have never shown any interest in the nest box, where ever it was. Never even seen them go in or sit on it. They nested their first brood last year in another snag that had a hole about 20 feet up, but that snag fell over last summer so they moved to the one they like now.

The only birds showing interest in the nest box have been the HOSPs (trapped 1 last year, 2 this year with the Van ert) and some HOWRs last year after which I removed their sticks and left the box open. Fortunately this year the HOSPs have since stayed away more or less and no sign of any HOWRs. X my fingers they stay away.

I speculate that perhaps these birds were raised in natural cavities and that is what they're most comfortable with?

There must be some way to baffle the tree?

You could try baffling the tree. I don't know how successful it would be, but surely it's better than nothing? I liked your idea of wrapping sheet metal around the trunk. You could wax the sheet metal to make it more slippery. Can't hurt, might help.

Hi kendra - that is interesting that the wax would make it more slippery. What kind of wax would I use?

I would think a smooth metal sheet would be slippery in and of itself. But I can't really hang the baffle like the ones on the feeder poles, which are the black stove-pipe type baffles that I bought at WBU. Supposedly the wobbly movement of the baffle makes it more difficult for the critter to get a grip and climb the pole.

I'm would like to give it a try. Climbing predators are no doubt a common threat to the bluebirds in the wild who prefer or have no other choice but to nest in natural cavities.

FYI: Have been googling this problem, and found many websites that discuss putting a sheet metal baffle around trees to prevent raccoons (and squirrels and rats) from climbing up trees. FOr example, to keep these critters from raiding fruit trees, or gaining access to a roof or chimney.

The website at the link below has drawings of raccoon baffles mounted on trees if you scroll down.

I'm going to try it!

Here is a link that might be useful: Raccoons - Washington dept of Fish & Wildlife