Dead baby blue tits

[pattie may]

Last year my husband put up a blue tit nest box in our garden and blue tit parents took up residence. Unfortunately after the storms in May the fence came loose. We checked the box a few days later and found four dead chicks. We assume the parents abandoned the nest.

Blue tit parents took up residence again this year and we saw them going in and out of the box. About a month ago the parents stopped visiting the nest. We checked it a couple of weeks later and found five dead chicks, of various sizes, and a small egg in the nest.

Can anyone offer any suggestions as to why the chicks died?

[Jenny W]

It could have been a number of things - one (or both) of the parent birds died, young inexperienced parents not feeding efficiently, reduced food availability, got wet and chilled, disease....plus more I can't think of!

[valleyforge]

There could be a whole range of possible scenarios to account for the death of ther chicks.

Here are just a few I can think of:

1). Death (probably by predation) of one or both parents ...
2). Parents unable to find sufficient food ...
3). Inexperienced parents ...
4). Investation of the nest by ticks or lice ...
5). Overheating of the nest box if it is placed in full sun ...
6). Chilling of the chicks if the nest box was exposed to driving rain ...
7). Toxic fumes emanating from creosote treatment of the fence ...
8). Stung by wasps looking to colonize the nest box ...

I expect others might be able to easily add to this ... it's a jungle out there

[SheffieldLass]

Those sound to be very small broods if they were abandoned for what ever reason and none had fledged. I think maybe they laid rather more than that but didn't have enough food for them all, so some made it to fledgling stage and the weaker ones didn't. So that could be from not enough food in the wild but both parents feeding, or because one parent died and the other couldn't manage to feed them all. And inexperienced parents may lay more than the conditions can support. I know my urban garden bluetits brood was compared with rural ones as part of research on whether urban gardens were as good as woodland. My inexperienced first year bluetits laid 13 eggs, more than the woodland, and I think 11 fledged .... did very well, and had their beaks constantly full of caterpillars ... no second rate food for their young .... so it turned out they had a very good environment in my garden for breeding. And they got the timing and numbers spot on, despite being first-timers .... Though once they had fledged one drowned in my pond, and the magpies and jays were on the lookout for an easy snack ...

Melanie

[pattie may]

Thanks for possible reasons.

I think that perhaps

1). Death (probably by predation) of one or both parents ...
2). Parents unable to find sufficient food ...
3). Inexperienced parents ...

could be cause

4). Investation of the nest by ticks or lice ...

none in nest

5). Overheating of the nest box if it is placed in full sun ...
6). Chilling of the chicks if the nest box was exposed to driving rain .

Nest is under bushes protected from sun and rain

7). Toxic fumes emanating from creosote treatment of the fence ...

Haven't treated fence this year - not the neighbour either

8). Stung by wasps looking to colonize the nest box ...

No evidence of this.

Really sad that this has happened two years running. Hopefully better luck next time.

[bobbarber]

really sad that this has happened two years running. Hopefully better luck next time.

Hello pattie may, a thought just occurred to me, is the nest box sited near a bird table or feeding station? The coming and going of other birds to feed could cause nest abandonment. If it is, maybe re-siting the box may help...Bob

[pattie may]

The nest box is about 10 yards away from the feeding station and is under a lot of bushes. The parents were feeding from the feeding station for a week or so before they disappeared.

What is the ideal situation for nest boxes? Distant and placements?

[Jenny W]

Originally Posted by bobbarber

is the nest box sited near a bird table or feeding station? The coming and going of other birds to feed could cause nest abandonment. If it is, maybe re-siting the box may help...Bob

I wouldn't have thought that Blue Tits would be spooked by this. They are quite a tolerant species and don't tend to abandon easily when disturbed (at least by us humans when we are checking the boxes for our nest records).

[SheffieldLass]

Mine have bred successfully about 4m away from a busy feeding station. Also mine (which were the ones that were the subject of research) who used that box, the female was colour-ringed and also had 2 blood-tests done during the breeding season as part of the licensed research, the chicks weighed and colour-ringed, and unfortunately the box had the attentions of a cat jumping up to and knocking the box, and did not desert. They fledged successfuly 11 of 13 chicks. I also had to put a temporary chicken wire fence below the box to stop the cat (not mine....) getting too close to the box.

Has the box had the attentions of a cat? I notice it is sited on a fence ... if one starts to regularly sit on the fence above it that would make the adults very wary .. there is a point at which their own safety/survival takes precedence over the survival of the chicks, but it takes a lot for them to abandon.

What I did notice is that you said that the box is under a lot of bushes .. (or did you mean the feeding station?) If the box is under a lot if bushes it might enable rodents to get in the box perhaps? Blue tits generally seem to select sites that have good vision from the hole and dearth of perching places next to it, so predators can't perch easily and reach in. Also check that the box dimensions are suitable. The distance from the hole to base of box is important to prevent predation.

Melanie

[Beekeeper]

I dont suppose it could be anything the bird box is coated with or perhaps made from that has become responsible for the death of the chicks.

Just a thought

BK