Advice needed, cowbird egg

11 years ago

I did my weekly check on the chickadee box and was proud to finally see eggs but not happy to see the cowbird egg. I haven't had this happen before. What should I do with it? If it hatches surely the chickadee babies will die, yet the cowbird is a native species. Wish I had a HOSP nest to transfer it to. I found a good video on cowbirds below. I wonder if reducing the hole size will help keep the cowbird out if it decides to come back? How can I put a hole reducer on a gilbertson box? It would have to be 1 1/4" for chickadees correct?

http://www.pbs.org/wgbh/nova/nature/gangster-birds.html

This post was edited by tmann05 on Wed, May 1, 13 at 17:10

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Comments (10)

lisa11310
10 years ago
I would get a hole reducer on and get rid of the egg. I know they are protected, but there are plenty of them and I am sure that is not the only egg the Cowbird has laid. 1Cowbird vs 5 or more Dees?
dzyg
10 years ago
I too would get rid of the egg and get a reducer on. 1 1/8 is good for Dees and would prevent the cowbird from getting back in.
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tmann05
Original Author
10 years ago
Thanks guys, I followed your advice and removed the egg. I made a home-made hole reducer out of a piece of cardboard and taped it inside the box to the front of the box. It's been taped to the hole from all angles. Hoping it will hold up. It is a 1 1/4" or as close as I could get eyeballing it. The chickadees accepted it after a few minutes. Cardboard was the only thing I could think of that is flexible yet sturdy since I have gilbertson boxes. Crossing my fingers for no cowbird attacks. Never had a cowbird egg in 13 years of backyard birding, but now my 1st year at my new house and 1st nest of chickadees ever, I get one.
renee_2006
10 years ago
Do you mean a PVC box? If so this is what I did to make a reducer. I took a black plastic coffee lid and used a metal 1 1/4" hole reducer as a template, drew around it, cut it out, I then heated the bolt on the stove to use as the holes maker then used the nuts and bolts to screw it on the pvc box on the inside.Works like a charm.
tmann05
Original Author
10 years ago
Yes renee I use gilbertson pvc boxes. Thanks for the tip. Just an update I checked the box today and only 3 eggs remain. Not sure what happened. Any ideas or advice for what to do next? Could the cowbird have stuck her head in the 1 1/4" hole and grabbed two eggs for retaliation? If this nest fails will the chickadees renest? How many broods do they have a year?
kendra2003
10 years ago
I hope this is what happened. I have had missing BCCH eggs before, only to discover she had hidden them under the "fluff" they use. Could you re-check and see if the eggs are just hidden? If not, have you heard any HOWR around? The House Wrens and very sneaky. If they stole the eggs, they usually pierce them and leave them on the ground near the box. You could look carefully and see if there are any eggs on the ground. I sure hope they're only hidden by fluff.
tmann05
Original Author
10 years ago
Well they don't seem to cover up the eggs when I check the box, maybe this is because she was scared out or bad parenting? I do have house wrens in the area as I have heard them. I am praying the 3 remaining eggs make it. I didnt see any eggs near the box.
tmann05
Original Author
10 years ago
I checked the box yesterday and there were two hatchlings and one egg. One hatchling didn't seem to be moving very much. Well I checked it again today to see if the third egg hatched and only found 1 hatchling left with the egg. This nest has just gone down hill from day one it seems. I read they only have one brood. I hope this chick makes it but if not I hope they try again.
tmann05
Original Author
10 years ago
Well bad news the solo nestling passed way today. No trauma or anything. Maybe the chickadees were just first year inexperienced parents? At any rate I removed the nest and saved it incase I need it in the future. Will they renest?
renee_2006
10 years ago
In the future incase of wrens you could make a wren guard and put it on after the first egg is layed.