I am from Rhode Island Trail is in northern RI Bluebirds are not hardy there flocks crash will high snow levels. And cold. Mild seasons they expand there local numbers. When there found dead in spring means there food supply was low and they expired. You will also see some dead threw out spring after a late cold snap the birds will just end up missing but we know it was the late cold snap. Many are weaken from the trip north once they show up and winter returns large numbers perish. It weeds out the old and sick. Ray

Sorry about the loss of your Bluebird babies! How sad! It could have been a number of things. Where are you and how hot was it there? It could have been the heat but I have heard of lots of babies doing just fine in this hot hot weather. I added head shields on my boxes for the first time this year to try to keep the box a bit cooler. Blowflies are a big problem this time of year. Were there any grayish short worm looking things in the nest when you took it out? I have lost baby Blues to blowflies before and try to watch the nests for them especially during the second nestings to clean it out or change it if I do see the larva. Also if something happened to one or both of the adults obviously the babies would die, one parent could feed them though and keep them alive. Did you feed mealworms at all? Has anyone around your neighborhood, or yourself sprayed you lawn or yard with pesticides or herbicides? That can kill baby birds when the parents feed them bugs that have the spray on them. Just some ideas, sometimes you just never know. Oh another thought, did you have a sparrow spooker up? Do you have any House Sparrows around, they will go in a nestbox and peck the babies to death, did the babies look pecked at all or where they dead too long to tell? So sorry this happened. Donna

Hi Mary- the only other possibility that I can think of is if something happened to one of the original mates & the remaining one found a new mate, the new mate will rarely have anything to do with the eggs/babies since they weren't their offspring. In this case, the new mate often steers the original mate away from the eggs/babies so they can try to produce their own (may not even try to produce since it's late in the nesting season). I would think it would be one of those scenarios. Research shows that it's about 10 degrees hotter in the box than it is outside. If it's in 90's, it could be too hot for them. Hatchlings can't regulate their own body temps for first 6 days. Risk would be same if too cold at beginning of season. If lawn pesticides (could be neighbor's if yard is close), babies are usually bloated. Did you notice anything unusual with them? Bloating or markings? Those are my only thoughts. Such a bummer & so sorry!

Hi Susan- Are you talking about the floor dimensions? They range according to what style of box you have (from 4" x 4" up to 5.5" I think). My other house is also decorative with a tin roof (smaller floor). That roof can definitely cause the heat to soar. My bluebirds used it before I got a proper bluebird box. Now, they definitely prefer the bluebird box. I'm going out of town for a couple of days, but would be happy to measure for you next week. In the meantime, ask on the other forum. There is a guy named Fred on there that is a total expert on bluebird box dimensions. Earlier in the season, there was a post about this that you may find helpful there. Is your hole diameter 1.5"? As you've read, there's not a lot of nesting going on right now. Nicole