Is this bird feeding fish a good Samaritan or is it just confused? Find out what experts say.
First it was the lost narwhal adopted by friendly beluga whales. Then it was the lioness nursing the leopard cub. Then came the duck raised by an owl. And now in the latest example of interspecies care, here’s a cardinal feeding goldfish.
Originally posted on YouTube in 2010, the video below shows the vividly colored bird hopping by a goldfish pond, then dropping what appears to be seeds into the fish’s waiting mouths.
According to the original caption, the cardinal would come back to the pond to feed the fish as many as 6 times a day.
But what’s behind this unusual relationship? Why would a bird feed an entirely different species? National Geographic interviewed Princeton biologist Christina Riehl to find out.
“My best guess is that the appearance of the goldfish’s open mouth at the surface of the water is just similar enough in size and shape to the open mouth of a baby bird that it triggers the instinct in the adult bird to provide food to it,” says Riehl.
To call their parent’s attention to their need of food, the mouths of nestlings tend to be vibrantly colored, often in bright red and yellow. It’s a visual cue that acts like a bull’s-eye for the parents – “Feed me here!”
“It’s an amazing demonstration of how simple stimuli can trigger very hardwired behaviors, even in situations that seem obviously wrong to us,” Riehl says.
Yet, biologically speaking the bird is definitely wasting it’s time. “Especially if the cardinal is feeding goldfish instead of feeding its own young,” she adds.
The cardinal-feeding-goldfish video is not the first record of this kind of behavior.
According to Robert Mulvihill, an ornithologist at the National Aviary in Pittsburgh, Pennsylvania, back in the 1960s the LIFE Nature Library books ran a black-and-white photograph of a cardinal feeding a goldfish.
“The explanation, as best I can recall, was that it represented redirected parental feeding behavior, perhaps on the part of a bird that recently had lost its own brood,” says Mulvihill. This underlines Riehl’s hypothesis.
Interestingly, there are quite a few other clips online that show birds “feeding” goldfish or other fish. Check out these swans feeding koicarp, for example.
Or this duckling doing the same.
But is this the same behavior? Riehl isn’t so sure. Newborn cardinal chicks are altricial, which means they’re naked, blind, and reliant on their parents for everything. However, most waterfowl young are precocial, which means they’re open-eyed, fluffy, and capable of leaving the nest soon after hatching, she explains.
So the similar reaction is surprising. But J. Dale James, director of conservation science and planning for Ducks Unlimited, has an explanation.
“Both the swans and the duckling look to me to be in a captive type of environment,” James points out.
“As such, they are probably eating pellet type foods and it’s not unusual that they dip those in water while eating.”
But then, the takeaway is that we are only guessing what might cause this curious cross-species caring.