This innocent, awkwardly cute, baby bird made me angry this week.
For several days it cried loudly and incessantly from the dogwood tree outside our screen door. The cries temporarily stopped each time its parent brought back a caterpillar or other insect to satisfy its voracious hunger. And then it resumed, over and over. That’s not what made me mad though.
The parent dutifully hunting down and delivering all those insects was a Red-eyed Vireo. The fledgling eating all those insects however was not. It was a Brown-headed Cowbird, a brood parasite (biology’s term, not mine). The Red-eyed Vireo had been tricked into raising this interloper, at the expense of its own young.
Cornell Lab’s All About Birds objectively calls the Brown-headed Cowbird’s parasitism “a fascinating approach to raising its young.” I’d call it unfair, but we’re talking about birds, so that would be unfair. As All About Birds explains: “Females forgo building nests and instead put all their energy into producing eggs, sometimes more than three dozen a summer. These they lay in the nests of other birds, abandoning their young to foster parents, usually at the expense of at least some of the host’s own chicks.”
Brown-headed Cowbirds are native to the United States, so they’re protected by the Migratory Bird Treaty Act of 1918, one of the oldest environmental protection laws on the books. The MBTA protects native birds from people, so you can’t hunt, capture, kill, or otherwise hurt cowbirds or their eggs, even if you think they’re a nuisance. (The exceptions are non-native House Sparrows and European Starlings.) It’s an important law that’s estimated to have saved millions of birds, though the current administration is moving to weaken its protections.
Years ago, when I learned about Brown-headed Cowbirds and then saw some in our yard I judgmentally said, “I hate cowbirds.” My youngest immediately said, “you can’t hate a bird for being itself!” She was right. A cowbird is just being a cowbird, like all the other cowbirds before it.
After all, I also like raptors and hawks and corvids, and they can be brutal. I’ve watched a hawk hunt in our yard, gulls fight over a dead bird on a beach, and I know the crows and ravens are likely eating eggs and baby birds right out of their nests. Nature doesn’t need nor care about our judgement, though it could use our attention and protection.
Thankfully, I don’t often see Brown-headed Cowbirds in our yard and there are ways to discourage them. However, last month by chance I saw a female cowbird fly from the previously mentioned dogwood tree carrying an egg it had removed from someone’s nest. It then dropped it on the ground a few times for good measure. That a cowbird fledgling appeared a few weeks later was not a big surprise.
It’s unreasonable to judge a bird or any animal based on a human sense of fairness. Still, when I realized that this crying fledgling was a cowbird, not a vireo, it transformed in my mind from adorable to menacing. The Red-eyed Vireo parent and the young Brown-headed Cowbird didn’t know the difference though. They were operating on instinct. I was the one hung up on baby vireos who never got a chance, let alone a caterpillar, and that wasted egg on the ground.
So, does one cowbird replacing one vireo clutch matter? It is part of nature after all.
Maybe it wouldn’t matter if bird populations weren’t declining so rapidly: Eastern forest birds have declined 27 percent in the past 50 years. Thankfully in this case, the Red-eyed Vireo is one of the most common breeding songbirds and a species of “Least Concern” for conservation. Though it’s not the only species Brown-headed Cowbirds select as a host; more than 140 bird species have raised cowbird young. Cowbirds have also been implicated in the decline of several endangered ones, including the Kirtland’s Warbler and Black-capped Vireo. And as species decline, it starts to feel like every bird matters.
And maybe one cowbird wouldn’t matter if 2.5 million acres of grasslands weren’t being lost or degraded annually: Brown-headed Cowbirds were once confined to open grasslands, following herds of North American Bison around to eat the insects they stirred up. As people spread out, settled, built towns, and cleared woods the cowbirds dispersed as well. Now they cover far more territory across the continent and utilize more host species who never dealt with their parasitism before.
And maybe one cowbird wouldn’t matter if insects weren’t dying off at alarming rates due to pesticides, habitat destruction, climate change, pollution, and invasive species. It’s estimated 40 percent of insect species are declining; a third are endangered and facing extinction in the coming decades; and insects are disappearing eight times faster than mammals, birds, and reptiles. All those caterpillars are essential to baby birds—who each need to eat thousands to survive—and to the insect populations that pollinate, maintain soil structure, and support food chains and ecosystems.
But all these things are happening, right now.
So, I’m not angry at that hungry little cowbird who just wants to survive; I’m angry that we’re losing millions of birds and insects, essential habitats and ecosystems, and biodiversity; at climate change; at a federal government ripping away environmental protections while actively causing harm to our land, water, and air. Amid all these environmental threats, the survival of a baby bird, a species, an ecosystem can feel tenuous. Like it can all come down to one last caterpillar.
We can’t judge the character of birds. One bird isn’t innocent and the other guilty. That doesn’t mean we leave nature alone to fend for itself though. Because we’ve never left nature alone. We constantly tip the scales against it; we should also put a hand on the scales and help tip them back.
Planting native trees and plants to support birds and insects, preventing bird-window collisions, leaving the leaves on the ground, avoiding pesticides, signing up for action alerts, supporting cleaner energy, asking elected officials to defend and fully support the Migratory Bird Treaty Act and Endangered Species Act, fighting rescission of the 2001 Roadless Rule which will allow clear cutting of our National Forests, protecting our National Monuments from oil drilling and other harm.
If you love birds—and I do love birds, even that “fascinating” cowbird—there are many ways to fight for them, and the habitats, plants, and insects they rely on.
Turns out my anger was never about those birds in the dogwood tree, but all the environmental injustices that they, and we, face.
All photos copyright Alicia MacLeay and taken in Kennebec County, Maine, 2025