For the Birds Radio Program: Altruism
Laura gives some intriguing stories of birds taking care of the young of other species, and also of birds caring for adults of their own species.
Transcript
Like movie stars, birds are known throughout the world for their beauty and song, but not for any sense of kindness or altruism. In a dog-eat-dog world, some birds learn survival of the fittest early: herons, hawks, and owls often kill smaller brothers and sisters in the nest, sometimes eating them. Although birds are both sensible and fragile enough to avoid most fights with territorial song, they can be vicious when they do set to fighting.
But a surprising number of individual birds perform acts of genuine kindness toward individuals of their own or even different species. There are many cases of adult birds feeding babies of other species. One Eastern Phoebe whose own babies had reached independence took to feeding a family of baby Tree Swallows, whose parents didn’t appreciate the help. They tried their hardest to drive away the phoebe, but she fed the babies for a week.
One Eastern Bluebird fed a family of House Wrens until his own eggs hatched. When a male Carolina Wren started feeding a female House Wren and then her babies, her real mate deserted. The Carolina Wren was such a devoted foster father that the natural mother eventually left him in full charge.
In Ontario, a male Prothonotary Warbler, the only one for at least 50 miles around, took to feeding a female Yellow Warbler as she incubated her eggs. When the eggs hatched into full-blooded Yellow Warblers, the Prothonotary fed them, and the natural father, perhaps doubting the paternity of the young, deserted. For several years, this Prothonotary Warbler helped with the raising of Yellow Warbler babies, even learning to sing a credible Yellow Warbler song, but he never did manage to father any young of his own.
A male cardinal whose nest was destroyed helped feed four fledgling robins for a week—his help seemed to be appreciated by the robin adults. Another really desperate cardinal who lost his mate and babies stuffed food into the mouths of goldfish at a pool’s edge for several weeks.
There are many cases of two different kinds of birds sharing a single nest. Mourning Doves and robins, cardinals and Song Sparrows, House Finches and robins—all have cooperated in incubating eggs of both species and then feeding the babies. Obviously this practice is more likely to have a positive outcome when the babies all hatch out at the same time.
My favorite story of birds helping others are when birds transcend the mere instinct to feed young. One old, blind pelican was kept alive for a long time by other birds in its colony who brought him fish. A Brown Booby on an island off the west coast of Mexico was born with a withered, useless wing and never flew. The members of his flock fed and nurtured him throughout a long life, continuing to bring him food long after he reached adulthood. And several adult Blue Jays, nature’s perfect bird, fed and guarded an old, partially blind jay and carefully led him to water.
All in all, over 130 species of birds have been recorded helping others. Maybe birds are more altruistic than they’re cracked up to be.