I have the exact egg combo in a nest in one of our hanging ferns! 3 blue eggs and 2 dark speckled eggs. How can this be? Same bird mother? Or nest competition and two mothers claiming one nest? But then again, we have hung ferns in the same places for 23 years and I have to say this is the first time we have had this happen. Would live for an ornithologist to offer some reasonable explanation. These having ferns of ours typically birth 12 to 15 new birds each spring. I just love this event!!!
Hi Susanne, This sounds like you probably have a House Finch nest with two cowbird eggs. Brown-headed Cowbirds are a native and protected species that reproduces by laying its eggs in other birds’ nests. You can learn more about these birds here. Note that Brown-headed Cowbird chicks don’t always do well in House Finch nests because House Finches are one of the few songbirds that feeds their young a mostly vegetarian diet, while cowbirds really thrive on the protein that insects provide. The best way to proceed here is to continue monitoring as normal! We also invite you to submit your observations to NestWatch – learn more here.
This is the 4th batch of birds in this nest and it’s only June 19 in Iowa. Looked like purple finches the first 3 batches, mom and dad always together. Last week 3 flew away and now I have a blue and a larger brown specked. I’ve documented with pictures all the eggs. 2 times when 4 eggs were in the nest, one would be kicked out. I only presume there wasn’t enough room… could that be true? I now see what I think is a brown striped bird on the nest and a bright red ( purple finch ) dad on watchpatrol. Interesting…
Hi Lynn, the brown-striped bird is a female finch – both House Finch (that are more likely to nest on human structures) and Purple Finch females are more drab in color than the males. If you see a white egg with brown speckling in the nest, this is likely a Brown-headed Cowbird egg. Brown-headed Cowbirds lay eggs in other birds’ nests and sometimes kick out host bird eggs and outcompete their young, a behavior known as brood parasitism. That said, cowbird young tend to do poorly in House Finch nests because cowbird young need insects to grow strongly, and House Finches feed their young a mainly vegetarian diet. If you have more questions, please email nestwatch@cornell.edu.
Hi Kimberly, You do not need to interfere with this nest. Brown-headed Cowbirds are native birds to North America and therefore protected. Additionally, cowbirds tend to do poorly in House Finch nests, because cowbirds need the protein from insects to grow strongly, and the finches feed their young a mainly vegetarian diet. You can learn more about cowbirds here.
Hi Louis, The two speckled eggs are Brown-headed Cowbird eggs. http://nestwatch.org/learn/general-bird-nest-info/brown-headed-cowbirds/ The other 3 are blue and probably bluebird eggs (not many other box-nesting birds have blue eggs).
I have the exact egg combo in a nest in one of our hanging ferns! 3 blue eggs and 2 dark speckled eggs. How can this be? Same bird mother? Or nest competition and two mothers claiming one nest? But then again, we have hung ferns in the same places for 23 years and I have to say this is the first time we have had this happen. Would live for an ornithologist to offer some reasonable explanation. These having ferns of ours typically birth 12 to 15 new birds each spring. I just love this event!!!
Hi Susanne, This sounds like you probably have a House Finch nest with two cowbird eggs. Brown-headed Cowbirds are a native and protected species that reproduces by laying its eggs in other birds’ nests. You can learn more about these birds here. Note that Brown-headed Cowbird chicks don’t always do well in House Finch nests because House Finches are one of the few songbirds that feeds their young a mostly vegetarian diet, while cowbirds really thrive on the protein that insects provide. The best way to proceed here is to continue monitoring as normal! We also invite you to submit your observations to NestWatch – learn more here.
This is the 4th batch of birds in this nest and it’s only June 19 in Iowa. Looked like purple finches the first 3 batches, mom and dad always together. Last week 3 flew away and now I have a blue and a larger brown specked. I’ve documented with pictures all the eggs. 2 times when 4 eggs were in the nest, one would be kicked out. I only presume there wasn’t enough room… could that be true? I now see what I think is a brown striped bird on the nest and a bright red ( purple finch ) dad on watchpatrol. Interesting…
Hi Lynn, the brown-striped bird is a female finch – both House Finch (that are more likely to nest on human structures) and Purple Finch females are more drab in color than the males. If you see a white egg with brown speckling in the nest, this is likely a Brown-headed Cowbird egg. Brown-headed Cowbirds lay eggs in other birds’ nests and sometimes kick out host bird eggs and outcompete their young, a behavior known as brood parasitism. That said, cowbird young tend to do poorly in House Finch nests because cowbird young need insects to grow strongly, and House Finches feed their young a mainly vegetarian diet. If you have more questions, please email nestwatch@cornell.edu.
I have the same situation. Cow bird egg in with my house finch eggs. Should I remove the cow bird egg or just leave it?
Hi Kimberly, You do not need to interfere with this nest. Brown-headed Cowbirds are native birds to North America and therefore protected. Additionally, cowbirds tend to do poorly in House Finch nests, because cowbirds need the protein from insects to grow strongly, and the finches feed their young a mainly vegetarian diet. You can learn more about cowbirds here.