The crow and blowflies
American Crow on the Bluebird Box
Yes the crow could hear the baby nestlings inside the box! What do you think happened next?
Hmm what’s inside?
Here comes dad to save the day!
Zing . . . . right past the crows head!
Actually the crow wasn’t able to reach the nestlings but I don’t blame the crow for trying! Dad eventually convinced the crow to move onward and then mom started feeding the babies again. I took these crow photos 11 days ago and the baby bluebirds were doing great (so I thought). I knew something wasn’t right when I opened the box last Friday and the nestlings should have been almost ready to fledge the nest. I noticed that the babies were not moving, still extremely tiny and cold when I touched them! I investigated the nest and found that the box was infested with blowflies. Julie has some good photos if you wondered what the blowflies look like.
Blowflies are parasites that attach to the baby birds and suck their blood. Obviously the blowflies don’t want to kill the host bird . . . . but when you have cold/wet weather like we had this past week . . . the parents are unable to give the nestlings enough insects to survive and the babies become casualties. I wish I hadn’t been so busy and checked the box more frequently . . . maybe I could have saved them?? Now I need to make time to check all other bazillion boxes that I monitor!!
Eastern Bluebird that I photographed at the box yesterday!
BTW: I have already noticed the female started to rebuild in the other nest box that I have. Friday I thoroughly cleaned the infected box up and should be ready for its next occupant.
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I don’t blame the crow either. It’s a shame about the babies though.
27 May 2008 at 8:59 am
😦 Poor babies. Love those crow pictures!
27 May 2008 at 9:49 am
Great photos. Can’t blame a crow for trying. Blowflies, on the other hand, rank right up there with fire ants in my book. Kill them all! (Yeah, I know, it’s just Nature..) Hopefully her second brood will have more success.
27 May 2008 at 9:51 am
Too bad about the baby bluebirds but we can learn from the mother moving on.
27 May 2008 at 9:57 am
For the first time, I have crows doing acrobats at my littlest bird-feeders, the ones mostly finches and nuthatches, etc. use. The crows have never bothered these feeders before. I wonder what gives.
27 May 2008 at 10:04 am
Interesting story and pictures…but sad about the babies. I don’t think I want to check out the pictures of the blowflies. Seems kind of creepy! Good for the mother to start over again, though…
27 May 2008 at 10:24 am
I don’t care for crows much but your pictures make them look “pretty,” so black and shiny. We have crows around here and I never imagined anything but a cat had gotten my baby finches. Perhaps a crow could have found them. Great pictures and too bad about the baby bluebirds, my favorite bird of all.
27 May 2008 at 10:41 am
aww that’s too bad (about the blowflies) what a shame. It makes me want to check my boxes but I’ll allow them the ability to work it out. I’ve had lots of crows (and thus, casualties this year) There must have been six very large guys swarming my trees. dang… The good news I’ve seen lots of small fledged crossbills this year. One species are outwitting the crows!
27 May 2008 at 10:54 am
@ Lynne – Thanks and it is a shame!
@ Liza – I know exactly how you feel!
@ obi – thanks and it did try! I wasn’t happy when I found them in the box!
@ joan – I know and I hope the other boxes didn’t get hit like this!
@ Bo – Sometimes I wonder if the crows do these things because its fun?
@ Rondi – thanks and it was dad! Julie had a great post on them also!
@ Linda – They are neat birds but it is possible they or bluejays got them! Also Red Squirrels take many young!
@ aullori – I know! I need to go check all my other boxes also! Very cool with the Crossbills!
27 May 2008 at 12:30 pm
How sad! I doubt there is much that you could have done about it. The parent bluebirds are better equipped to find the food the babies need. Hopefully they will nest again.
27 May 2008 at 12:31 pm
Amazing series of shots, and what a roller coaster of emotions!
Fantastic work, Monarch
27 May 2008 at 1:17 pm
So sorry about the bluebirds. But se la vie. That is nature’s way.
27 May 2008 at 2:58 pm
Oh poor babies-bajillion huh? that outa keep you busy allright because I know you don’t have enough to do now-LOL
I love the dad BLUR going by 😀
27 May 2008 at 4:06 pm
Oh that sucks!!! I’m sorry the blowflies won this time….they won’t next time! Good luck with the rest of the bazillion houses!
27 May 2008 at 5:37 pm
The more I love nature the more I realize nature can be cruel. I read Julies post and learned quite a bit. Hope you have some help checking your other boxes.
27 May 2008 at 8:12 pm
Those poor bluebirds. First Crows then blowflies. YUCK. Interesting photos of the crow looking into the box.
27 May 2008 at 8:36 pm
@ John – I might have been able to pick off the blow flies and better its chances of surviving! They are already nest building!
@ monica – thanks and nature can be a roller coaster of emotion!
@ scienceguy – thanks but I am sure you wouldn’t have felt that way if you found them dead!
@ Marg – Seems like that many! I liked the dad blur shots also!
@ Chicago – I hope their isn’t a next time but I know that will not be true!
@ Toni – Nature is very cruel at times! It’s just me checking the boxes!
@ Lisa – thanks and you could almost see it “think”!
27 May 2008 at 8:49 pm
Awww. Drats
I’m watching a Bluebird box at work. They’re eyes are open now and they’re blue. No blowflies that I can see…
The adult bluebirds are so busy right now and I can’t keep up with their activity but I take mealworms to them every morning. I think they know me :o) There’s one box I’m getting worried about and I’ll investigate more tomorrow. It looks like an adult has been in that box for too long but it’s alive.
Can’t blame the crow…
27 May 2008 at 10:51 pm
That’s so sad. 😦 If you had picked the blowflies off, would the parents still care for the babies? I have always heard that if you bother a nest or handle babies, the parents will abandon them. Is that an old wives’ tale?
27 May 2008 at 11:01 pm
@ Mary – the eyes being open is a great age! Do check the box tomorrow!
@ Amy – it is and if I picked them off early enough . . . the young probably would have been able to feed them enough to survive! Turkey Vultures can smell but songbirds can’t! It’s the predators that you have to worry about smelling the baby birds when you handle them! This is a situation (obviously the crows know they are there) that it would be more benefit to pick the blowflies than worry about predators finding them (since they are safer inside the box). Having parents tell them to leave them alone is more to avoid having the kids pick up every single baby (who would have predator problems in the future). Ok, maybe a few other problems but you get the point!
27 May 2008 at 11:53 pm
I had never heard of this – I might have to check out the local bluebird boxes to see if it’s a problem there!
28 May 2008 at 8:42 am
What a shame! Last year we had a mockingbird with three babies in a shrub out front. They were so cute and then all of a sudden some were dead and one was on the ground. It was very traumatic!
28 May 2008 at 1:46 pm
I had a sad baby bird story, too. I have bird feeders out front for the first time, and unknown to me in my busy-ness, a pair of House Finches nested in the large hanging light holder outside over the front door. (The light has been out for some months). We had very windy weather lately, and I was cleaning the areas around the doors – and came across 5 dead babies on the front door mat covered in ants. I cleaned it all up, and the next day the sixth was on the door mat covered in ants. Since there was no trail to the mat, I assume that the ants found the nest and killed the babies there. I am thinking of putting up a bird box next year, but it would have to be ant-proof. I have to be more vigilant next year. But, I was so busy with work and used the front side door all the time so did not notice their activity.
30 May 2008 at 11:24 am
Great photos, Tom. I’m not trying to make light of this particular situation, but having seen so many nesting failures — for one reason or another — I sometimes think it’s a wonder we have any birds at all, but thankfully, we do.
31 May 2008 at 3:05 am
I had no idea blowflies would infest the birds like that! As for nature being nature, well, I had a raven kill a mourning dove at my feeder today and proceed to consume it right outside my window! (I wrote a post about it.) Glad the crow didn’t get those babies but it seems like to wouldn’t have mattered since the blowflies killed them anyway.
2 June 2008 at 8:54 pm
Hi Mon@arch,
This is exactly what I love about your blog. I would never be able to interpret sightings the way you do. It’s like getting an excellent tour guide at a fabulous museum.
4 June 2008 at 5:38 pm