In the spring of 2015, a male House Wren and his mate built their nest inside a nestbox near a honeysuckle. His mate laid her eggs and dutifully incubated them. Then, one morning— cheep! cheep! High-pitched calls and gaping red mouths cried hungry, daddy! and the male wren was off in a paternal tizzy, collecting bugs and delivering them to his new offspring.
It was, maybe, odd that his new offspring weren’t in the nest that he had built. It was, maybe, odd that other, larger birds were also feeding his babies. It might even have been called odd that his mate was still sitting in their nest, atop whole and silent eggs. But— cheep! No time for that! The chicks were hungry!
What this male House Wren was doing, no doubt to the profound irritation of his mate, was feeding the offspring of a pair of Northern Cardinals who had nested in the honeysuckle near his nestbox.
Egrets are beautiful, especially in their breeding plumage, when they sport long curved plumes and dramatically colored faces.
Great Egret displaying breeding plumes and a green face.
Snowy Egret with similar plumes and a red face.
Those breeding plumes are so beautiful that demand for them—for decorating women’s hats—almost drove egrets to extinction, and concern for the heavily persecuted egrets is what gave rise to the bird conservation movement in the early 20th century.
Egrets earn those luscious plumes. Before they get to be adults in breeding plumage, egrets must survive a cutthroat childhood in considerably less impressive dress.
Yikes, THAT’S what our chicks look like??
Ranitomeya imitator giving his tadpole a piggy-back ride. Photo by John Clare*
You can find poison frogs at zoos, aquaria, and some museums now: tiny and colorful, often hard to see in the vegetation-rich tank until— oh! all those little blue things, that’s them! They’re so pretty! You watch for a while, and they sit on their leaves unmoving, doing accurate impressions of the plastic toy frogs being sold in the gift shop, until you get bored and move on to the next exhibit.
They have a secret: they have rich lives full of interesting behaviors. They just aren’t interested in doing those behaviors in front of you.
Recently I was lucky enough to spend some time in Spain, where the land is dotted with hilltop castles and the winding narrow streets of the old cities are encircled by sturdy stone walls. I crouched behind crenellations, pretending to be a bowman awaiting attack, and climbed dark winding staircases glad that no defending army waited at the top.
Winding staircase in the Olvera castle.
Photo by Q. Stedman
It’s exciting and romantic to imagine castles and walled cities in the flush of functionality, but it’s hard to ignore that the motivating force for those structures was real, unromantic, gut-knotting peril and fear. The people who lived in those cities put up thick stone walls with their hands because they thought other people were going to come and unromantically kill them—which they sometimes did.
Gulls standing guard over Tarifa.
When birds build nests, they’re responding to that same threat. Eggs and baby birds are easy targets for anything from mice to snakes to deer to toucans. To keep them safe, birds too rely on stout walls, secret passageways, and defending armies.
Sometimes the titles of scientific papers are so surprising that they seem to transform into news headlines in my head:
Adoption of chicks by the Pied Avocet – Adoption of fledglings by Black and Red Kites – Caspian Terns fledge a Ring-billed Gull chick – Adoption of young Common Buzzards by White-tailed Sea Eagles
How can this be true? Raising chicks is hard; it takes energy and time and risk. Why would any bird make those sacrifices for an unrelated chick?
Okay, I would absolutely adopt this guy.
Pied Avocet chick. Photo by Keith Marshall
In general, we understand red birds thusly: the brighter the red, the better the bird. (Why? See this post.) The better the bird, the better his genes/parental care/mate, and the better his reproductive success.
But sometimes it’s more complex—and interesting—than that.
Red male House Finch. Photo by M. LaBarbera.
Yellow and orange male House Finches.
Photo by Ken-ichi Ueda.
EDIT 5/26/2016: If you found this post because you have a baby bird and are wondering what to do with it, please see this post instead; it will be more useful.
Being a fledgling—a chick that has left the nest—is awkward.
Junco fledgling MAII illustrates the awkwardness via interpretive dance.
Fledglings are at one of the most dangerous time in their lives, facing an average mortality rate of 42% over just a week or two. Most of that mortality happens early, just after the little guys have left the nest. New fledglings have almost no skills: they can’t feed themselves, can’t fly well (or, in many cases, at all) and can’t do anything to defend themselves if something terrifying like a weasel, snake, crow, or even chipmunk decides to eat them.