Cowbird present

[DocHeb]

My 10 year old daughter was pretty excited on my arrival home from work yesterday - "Daddy, we've got bird eggs in the nest!". From the recent activity we guessed the house finches were building a nest in the clematis - "and the momma laid two kinds of eggs!" I'm pretty sure the one speckled one is a cowbird egg, and the other four light blue are the finch eggs. I've heard that cowbirds do this surrogate mother thing, but have never seen it before.

 

[MossRoad]

Yep. That's what it looks like. It is a hard decision. Do you remove it to increase the survival chances of the finches or let nature take its course? In some areas, cow birds are wiping out populations of other birds. A female cowbird lays on average 40 eggs per year.

 

[patrickg]

Gee, an opportunity to show the kids "real" not Disney nature at work. NOT! If you aren't bothered by interfering with nature by mowing your lawn or swatting flies or putting antiseptic on a kids scratches then I think it isn't going overboard to "cull" the cowbird egg. But then I guess I'm not an unbiased observer as I like cute little birds and could do with a few less cowbirds.

Patrick (unabashedly messing with Ma Nature)

 

[GlueGuy]

Tough call Doc.

It's definitely "part of nature" for the cowbird to do its thing this way. In that respect, it's natural, & I'd say let it be. OTOH, the cowbird is also famous for taking advantage of the environment around a farm (where-ever cows, horses and livestock abound). In that respect, the cowbird has an "extra" advantage that is not natural. So in regard to "evening the balance" I might be inclined to intervene.

So I would base my decision on how many cowbirds are around, and whether you think they are "out of balance" with respect to other birds in that area. If there are already a boatload of cowbirds, and not many others, lean toward intervention. If the balance looks OK, let it go.

In our area, one neighbor has a bunch of critters, and we have almost none. He's got a bunch of cowbirds, and we have none. So in my case, if we saw a cowbird eggs in a nest, I'd probably let them go. If I were my neighbor, I might lean the other way (since he has the situation that unnaturally favors the cowbird).