In Africa, there are birds called oxpeckers (two species in genus Buphagus:yellow-billed and red-billed) that also perch on mammals and eat ticks, lice, fleas, and biting flies found on the animals’ skin. Studies have shown that individual oxpeckers eat up to 100 engorged ticks or 13,000 nymphs per day. Quite a benefit to the animal!
Yellow-billed oxpecker on a large bovine mammal in Africa (photo from Wikimedia Commons)
Engorged ticks contain tiny blood meals so it’s not a big leap that the oxpeckers sometimes to go directly to the blood source, pecking and plucking at an animal’s wounds. Despite this parasitic and perhaps painful behavior, many mammals tolerate the oxpeckers although elephants and some antelopes shoo them off when they land.
Yellow-headed caracaras are unrelated to oxpeckers but their tick-eating behavior extends to blood meals as well. The Handbook of the Birds of the World includes this remark about the caracara’s eating habits:
“Perches on cattle and Capybaras (Hydrochoerus hydrochaeris) to pick off ticks; picks flesh from open wounds on backs of cattle, which often seem oddly indifferent to the process.”
It sounds gruesome but the benefits of having your own portable tick-remover apparently outweigh the occasional blood meal.
(photos from Wikimedia Commons. Click on the images to see the original)
There’s a bird of prey in South America that likes to raid wasp nests to eat the larvae. The problem is that red-throated caracaras (Ibycter americanus) have bare skin on their faces and throats, an easy target for stinging wasps.
How do the birds get the larvae without a lot of pain? Do they chemically repel the wasps?
In 2013, Canadian Sean McCann and colleagues studied red-throated caracaras in French Guiana on the north coast of South America. They learned that, no, the birds don’t repel the wasps. The caracaras are attacked but they compensate in other ways.
Watch the video to see how the birds nab their tasty meal. They know something about wasp behavior that we had been ignoring.
Harmar bald eagle carrying nesting material in March 2013 (photo by Steve Gosser)
For one of Pittsburgh’s three bald eagle pairs, this year started off with a bang.
Since late 2013 the Harmar pair that nests along the Allegheny River have been hard to observe because PennDOT blocked off the nearest viewing area while building a replacement for the 107-year-old Hulton Bridge. Steve Gosser took the photo above from that viewing location in March 2013. It’s been hard to get good photos for years.
Last October the new bridge was completed and dedicated but the eagle viewing area was still closed while PennDOT began to deconstruct the old bridge. However …
Staff from the Audubon Society of Western Pennsylvania were on hand to monitor the eagles just in case. As ASWP reports below, the eagles weren’t affected at all. They were 3.4 miles away as the crow flies. (The eagles would have flown along the river, which is even longer.)
The Harmar eagles were down river near the Fox Chapel Yacht Club at the time. Our staff member monitoring the eagles said that the birds “didn’t even flinch” at the sound of the implosion.
The eagle viewing zone at Harmar will be closed a while longer but you can watch this pair easily now on the Audubon Society of Western Pennsylvania website. ASWP has both the Hays and Harmar eagles’ nests streaming live at eagles.aswp.org. Click here to watch.
Though the U.S. has banned lead shot in wetlands, it’s still present in fishing sinkers and the bullets used in deer hunting. Scavenging birds, including bald eagles, eat the gut piles hunters leave behind and are poisoned by the bullet fragments. Many die.
A 2012 bald eagle mortality study in the Upper Mississippi Valley found that 60% of the dead eagles had detectable concentrations of lead in their livers. 38% had lethal levels.
In 2012, researchers examined 58 dead bald eagles and identified lead exposure as a significant mortality factor (photo from U.S. Fish and Wildlife, Midwest Region)
Sadly, the problem is seen too often by veterinarians and wildlife rehabilitators.
Back in January 2009 I wrote about the dangers of lead poisoning and the sick eagle, pictured above, who was treated at Medina Raptor Center, Ohio. Click here to learn more in this 2009 blog post: Lead Poisoning
(photo from Wikimedia Commons. Click on the image to see the original)
Yellow-headed caracaras (Milvago chimachima) are omnivorous members of the falcon family who live in south-Central and South America. They eat almost anything — carrion, frogs, fish, eggs, palm fruit, corn, horse dung — but when it comes to feeding their young they focus a lot on insects. 90% of the nestlings’ diet consists of beetles, grasshoppers and crickets.
They earned their nickname “tickbirds” because they also glean ticks off of cattle and other mammals, including capybaras. Above, a juvenile yellow-faced caracara cleans a cow. The cattle don’t mind, even when the caracaras pick at open wounds.
Yellow-headed caracaras have adapted well as the forest is converted to ranches and cities. When they aren’t picking ticks off cattle they’re gregarious in town. You’d never guess from this video that their nickname is The Tickbird.
(videos from YouTube. The second video was filmed in Cali, Columbia)
The raven says many things. The snowy owl is unimpressed.
Notice at 1:20 in the video that the top of the raven’s head seems to grow “ears.” This dominance gesture means “I’m big! Watch out!” The owl doesn’t care and reaches over to peck the raven at 1:44. The raven’s ears go down … but up again at 2:09. What’s going on?
John Dunstan asked raven expert Bernd Heinrich, author of The Mind of the Raven, for an explanation and put Heinrich’s reply in the video description:
Naturalist Bernd Heinrich, author of “The Mind of the Raven”, was nice enough to provide this description.
The first thing to notice is that the owl is TOTALLY unimpressed. It’s not scared in the least, and the raven has no aggressive intentions, but starts out being just curious – like: “what the hell is This!” So it tests – tries to get a reaction. But the owl still stays totally nonchalant. At some point the raven then tries a different tactic – it puts on its “I’m a big guy” display of erect “ear” feathers – usually used to show status in the presence of potential superiors, but here used also with a bowing and wing-flaring, which is used in supplication if there is NOT going to be a challenge – so, yes, I think the raven was having fun, and then also starting to have some respect, because this big white thing was NOT going to cooperate and be its toy.
The comments on the video are priceless! Click here to see the video on YouTube and read the comments.
p.s. Ever since the snowy owl irruption of 2013-2014, Project Snowstorm has satellite tagged and tracked some of the snowy owls who visit the Lower 48 States. Click here to see maps and follow their stories of these amazing birds.