For starlings and meerkats in the Kalahari Desert, the fork-tailed drongo, a songbird with glossy black feathers and garnet-red eyes, is like the neighborhood dog: a trustworthy pal that’s always on the alert and ready to warn you about dangerous predators.
Except when it’s lying. Because sometimes drongos, which are about the size of a scrub jay, make false alarm calls, causing their listeners to drop whatever juicy morsels they were dining on and flee the scene.
Meanwhile the deceptive birds have swooped in and made off with their victim’s meal.
Indeed drongos are notorious among wildlife observers for their thieving ways. But sometimes the birds call “hawk” too often, and like the boy in Aesop’s fables who cried “wolf” one too many times, they discover that no one’s paying attention.
Now researchers report in Science that when that happens, the clever birds deploy another trick: They imitate their victim’s alarm call or that of another species.
The discovery reveals that drongos are paying surprisingly close attention to their target’s responses to their calls—perhaps even employing a type of sophisticated cognition that researchers usually reserve for humans only.
“It’s a really cool study,” says John Marzluff, a wildlife biologist at the University of Washington in Seattle. “It’s the most sophisticated example of vocal deception, outside of my own species, that I’ve ever seen.”
To study the drongos’ alarm calls, Tom Flower, an evolutionary biologist at South Africa’s University of Cape Town, has habituated and banded about 200 of the birds in the Kuruman River Reserve in the Kalahari Desert.
(It’s the same area occupied by the meerkats in the television series Meerkat Manor.)
“The Moon and the Crow”, Photograph by Gideon Knight of the United Kingdom, is the winner of the Young Wildlife Photographer of the Year award for 2016.
Knight lives near Valentines Park in London and he visits regularly in order to take photographs.
One winter evening the perfect tableau presented itself: a rising full moon set in the blue light of dusk formed the perfect backdrop for the spindly twigs of a sycamore tree upon which rested a solitary crow.
The various components of the scene “made it feel almost supernatural, like something out of a fairy tale,” said Gideon.
For the young photographer, this is one tale that’s come true.
Photography by Joel Forte, Antipolo City, Philippines – Photographed at Davao City, Philippines
If the irrevocable transition of one species from rarity to extinction causes a rent in the fabric of our planet, exactly how big a hole would be left by the loss of the Philippine eagle?
No disrespect is meant to the basking malachite damselfly or the fine-lined pocketbook mussel, because all creatures—and plants too—help turn the infinitely complex cogs of the biosphere.
But the loss of this glorious bird would steal some of the world’s wonder. It glides through its sole habitat, the rain forests of the Philippines, powerful wings spread to seven feet, navigating the tangled canopy with unexpected precision.
It is possible that no one has ever described this rare raptor, one of the world’s largest, without using the word “magnificent.” If there are those who did, then heaven heal their souls.
In the kind of irony all too familiar to conservationists, however, the very evolutionary adaptations that made it magnificent have also made it one of the planet’s most endangered birds of prey.
There is no competition for prey from tigers, leopards, bears, or wolves in the Philippine archipelago, the eagle’s only home, so it became, by default, the king of the rain forest.
Expanding into an empty ecological niche, it grew to a length of three feet and a weight of up to 14 pounds.
A nesting pair requires 25 to 50 square miles of forest to find enough prey—mammals such as flying lemurs and monkeys; snakes; and other birds—to feed themselves and the single young they produce every other year.
“The birds had the islands all to themselves, and they grew big,” says Filipino biologist Hector Miranda, who has studied the eagles extensively.
“But it was a trade-off, because the forest that created them is almost gone. And when the forest disappears—well, they’re at an evolutionary dead end.”