“Hey, Baby! I’m Feeling Great!” *cough cough* “Really!”
For the first half of the above video, a sick male zebra finch sits quietly on the floor of his cage. He’s not feeling so great, trying to rest and keep quiet while his immune system is in hyperdrive. But half an hour later, shown in the second half of the video, an unfamiliar female has entered the cage. To the male bird, that changes everything. He hops around with excitement and interest as if he didn’t feel sick at all.
Behavioral biologist Patricia Lopes of the University of California, Berkeley, and her colleagues injected this finch and others with bits of E. coli bacteria — triggering their immune systems without actually infecting them. They watched the birds as they lay sick, then compared how it behaved when a female was thrust into the picture, counting its hops and the time it spent resting. They found the male birds’ behavior changed completely, acting as if they weren’t sick in an effort to court the female.
Every morning and evening in the Amazon, wild parrots gather on exposed cliffs like this one to engage in geophagy, a fancy word for eating dirt. As the parrots scrape and lick the clay-rich soil, they socialize — loudly. “They’re all screaming their heads off,” says U.C. Davis conservation biologist James Gilardi. The smooth-textured clay, he says, acts like a water softener in the parrots’ guts, helping to neutralize the toxins the birds ingest from eating unripe and even poisonous seeds.
Gilardi studied two parrot “clay-licks” in Peru for his Ph.D thesis, and now runs a conservation organization called the World Parrot Trust. Despite their popularity, parrots remain mysterious in the wild. Geophagy is just one example of a behavior that has been largely overlooked. Gilardi studies wild parrots in the hopes of conserving them in their native habitats and allowing people to take better care of them as pets. This week, his team published new evidence in PLoS ONE showing that parrots seek out bitter, toxic foods other animals won’t touch.
To catch the birds snacking, Gilardi and his team spent several summers walking through Manu National Park in the Peruvian Amazon. They spent up to ten hours per day watching from the ground for parrots rustling in the canopy and listening for squawking cries or the sound of falling fruit. When they found the parrots, they wrote down the kind of tree the birds were in, and noted what dropped on the ground. They also climbed the trees to collect samples, and sat in the canopy watching the birds fly and forage. They wanted to know whether the birds preferred seeds or fruits, how thoroughly they “demolished” their food, as Gilardi puts it, and whether they gobbled up ripe or unripe fruit and seeds. Parrots are messy eaters, but it was soon clear that the birds were going after unripe seeds. Many of these are protected by bitter, potentially toxic substances like alkaloids, found in substances like hemlock and strychnine.
The parrots weren’t just swallowing seeds and pooping them out intact, like many animals do. Instead, they were digesting them. This wasn’t a surprise, says Gilardi. Large macaws can destroy softball-sized seeds with their beaks, cracking shells that would take a monkey many blows with a rock to break apart. “Anyone who’s ever watched parrots in the wild knows that they are destroying seeds.” What surprised him was the toxicity of the seeds they were digesting: “A lot of the things they’re eating are pretty nasty.” Sometimes they would see a tree full of fruit which other birds or animals shunned. Then the parrots would arrive and “just plough through” it.
In addition to detoxifying their systems by eating clay, Gilardi says that parrots’ livers and other aspects of their physiology are better equipped than ours to deal with poisonous substances. Although parrots are one of the most endangered bird species in the world, parrot conservation almost never has anything to do with food. “It’s one less thing to worry about.”
More often the threat is habitat destruction and capture. “Parrots are often threatened by something local to them,” says Gilardi. Parrot trafficking for pet sales, in addition to the clearing of tropical forests, threatens roughly more than one in four parrot species — about 95 out of 360 total. Although the World Parrot Trust doesn’t condemn bird-keeping, it works to protect parrot habitat, eliminate illegal and unsustainable parrot trafficking, and help pet owners care for their birds correctly. “If we’re going to do this,” he says, “let’s do it right.”
People tend to feed parrots things people like to eat: cereal crops that have been heated up, cooked, and shaped into pellets. They feed them ripe fruit when a parrot might actually prefer something as astringent as an unripe persimmon. “It’s a huge problem,” says Gilardi. He hopes that people will consider that their backyards might be a better place to find parrot food than the grocery store.
Photo credit: Wikipedia Commons
In December my sweetheart and I embarked on a road-trip to visit family. Our route made a triangle whose sides add up to about 1,800 miles — from Baltimore to Traverse City, to Indianapolis, and back to Baltimore. The trip was pretty uneventful…except for the birds.
This winter has been remarkably mild in the Midwest, and Beth (the sweetheart I mentioned) and I saw little snow or rain on our trip, which meant no white-knuckled driving or low visibility. So we just plugged in the iPod, put it on shuffle, looked out the windows and caught up on all the conversations we’ve been too busy to have or too preoccupied to think about. Great conditions for spotting something strange in the landscape.
My parents live on a small lake near Traverse City. If you hold out your left hand, with your palm facing away, you’re looking at a basic map of Michigan’s lower peninsula (they call it “The Mitten” for a reason). Traverse City is in that little nook between your pinky and ring fingers. At my parents’ place, depending on the season, we see hummingbirds, seagulls, a crazy-huge woodpecker once in a while, a bunch of bird-feeder types, and an endless parade of ducks and ducklings. This winter brought a shocker though.
Beth and I had spent a couple days at my parents’ place and were about to drive down to my brother’s place near Indianapolis. But as I was making my final “pitstop” before getting in the car, Beth came and found me, saying there was an owl outside. We went up to the second floor, where my parents were looking out their bedroom window. Down below, standing in the snow on the edge of Lake Leelanau, was a snowy owl.
Weeks later, National Public Radio would run a story about how snowy owls were being sighted all over the place. All I knew was that I’d never seen an owl in the wild. The National Zoo in D.C. has some charming specimens (one locked eyes with me and tracked me as I moved around the room — my black plastic frames look remarkably similar to the owl’s coloring…) and I met a few owls face to face at the Maryland State Fair a couple years ago, but this was different. This was a wild bird, a huge bird with white feathers and yellow eyes. It was difficult to comprehend, or even to see. From the upstairs window, we were only about 70 feet away at most, but there was so much white from the snow and the feathers that it was hard to process just where the bird ended and the snow began.
Exciting, but the drive to Indy would take seven hours. We had to get going. Beth and I hit the road southbound. As we neared the Indiana border, I probably shouted “bird of prey!” Beth was driving at the time and I’m not sure where she finds patience for my behavior. I guess she’s come to expect the outbursts.
The bird I’d spotted became a speck in the rear view mirror, so we went back to chatting about whatever. A few minutes later, we saw another perched on a branch about halfway up a tree right by the highway. Less than five minutes after that, Beth spotted a bird of prey on the guardrail in the median. It was getting weird, I took out my camera and attached the zoom lens. I had a hard time getting a good photo through road-trip filthy windows and moving at highway speed, but the birds kept on coming.
For the next few hours, we saw these same birds every five to 30 minutes. On I-94, the birds perched on street lamps near Michigan City and Gary. On I-65, we saw them perched atop billboards. At least twice, we saw two together on a tree. They were brown, with white breast-feathers. My fascination with birds is a relatively new thing, so I’ve yet to make time to learn about them. Beyond cardinals, blue jays, cowbirds or doves, I can usually only recognize whether it’s bird of prey versus a songbird. This one we’d have to just look up later using the photos, and we had plenty of photo ops.
But why along the highway and why so many? Most, not all, were perched on the highway side of the tree rather than away from the highway where they would have a view of the farm fields. Why? I lived in Indiana for nine years, and Michigan for at least half as long, but I’d never seen predatory birds line the highways like that. By the time we arrived near Indy, I’d forgotten about the snowy owl in Traverse City.
The next morning, after some time with my brother and his family, Beth and I set out for the East Coast. I drove and Beth manned the camera. She’s the better photographer, so she got the best photo:
We saw the birds through Indiana and Ohio, and a few in West Virginia, but by Pennsylvania and Maryland, they dropped off to nil, which was disappointing because Beth and I were then left reflecting on how tired we were of being in a car. Still, I was hung up on the question: what was up with these birds?
Days later, I got in touch with Cheryl Dykstra, editor of the Journal of Raptor Research, and described the birds and where they were perched. Dykstra didn’t seem shocked at the number of sightings or the birds’ location. Most of the birds were “almost certainly” red-tailed hawks, Dykstra said. Maybe a few rough-legged hawks and red-shouldered hawks in the mix, she said. Apparently, hawks are all about hyphens. But what were they doing near the road?
“They perch facing the highway because foraging is probably better in the short mown grass along the highway than elsewhere — likely they can see the small mammals running through the short grass more easily,” Dykstra said. “So the edges of highways may be quite attractive to them.”
That’s it. Nothing abnormal about the hawks perched where they were. But Beth and I will still go on hawk-alert next time we’re on the road. Now that we know they’re out there, it’ll be impossible not to look for them. If we’re not willing to pull over and take a decent photo, then why bother? I don’t know. Nature is my brain candy, and spotting a hawk anywhere or anytime tastes pretty sweet. If Beth enjoys the flavor as well and we’re stuck in a car together, all the better.