Ok, not necessarily a MD/DC Bird thing, but still interesting.  Burrowing Owls using tools and  Ravens eating Eared Grebes in Yellowstone.

Denise Ryan
Washington, DC

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Scientific American.com

September 02, 2004   
 
Cunning Owls Bait Beetle Prey   
 
The wise old owl is a staple of nursery rhymes. New findings provide more evidence that the animals are, in fact, quite crafty. According to a report published today in the journal Nature, owls use mammal dung to lure prey. 
A few examples of avian tool use have been reported, but in many cases the birds were captive animals and it was difficult to assess the advantage their wild counterparts could glean from the behavior. In the new work, Douglas J. Levey of the University of Florida and his colleagues studied wild populations of burrowing owls (Athene cunicularia). The researchers removed all traces of mammal dung from the nests of two owl populations in Gilchrist County, Fla. Half of the nests then received an amount of dry dung typically found surrounding a nest. After four days, the researchers analyzed the birds' droppings and collected discarded remains of eaten beetles to determine the owls' diets. They discovered that owls with access to dung ate 10 times more dung beetles than those with bare nests did. 

The scientists also tested whether the owls might be using the dung to mask the scent of their nests, but found that it did not offer sufficient protection from predators. Instead, the owls appear to "fish" for dung beetles using excrement as bait. The results of this study, the authors conclude, provide "an unambiguous estimate of the importance of tool use in a wild animal." --Sarah Graham 

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Subject: Scientist writes about bird massacre ( Article in 8/30 Billings
Gazette and Bozeman Chronicle)

 Scientist writes about bird massacre Associated Press

 BOZEMAN (AP) - A Yellowstone National Park ornithologist who saw four
 ravens systematically kill 141 grebes describes the spectacle in the new issue of Yellowstone Science, a quarterly magazine.
 Terry McEneaney had known for a long time that ravens are efficient predators. But he was astonished last May when he saw four of them attack so many grebes on icy Yellowstone Lake.  Western-eared grebes generally do not spend much time in Yellowstone, but on May 1 hundreds passed overhead, en route north for the summer.  McEneaney was at the lake, looking for bald eagle nesting sites, when he saw a grebe on the frozen water. Shifting cloud shadows apparently had fooled the bird into thinking it was landing on open water.  "Then I saw another grebe, and another grebe, and another grebe,"McEneaney said. "They were all over the place."  Grebes need open water for takeoff, so once they landed, they were stuck there.  Enter the ravens.  At first, only one was on the ice. It "flew out to one of the stranded grebes and pulverized it with its long beak until it was dead," McEneaney wrote in the magazine.  The raven left the grebe where it lay, then moved to another and pecked it to death, as well. At about 11 ounces, grebes are much smaller than ravens.  Twenty minutes later, three more ravens joined in and started killing grebes.  Then two bald eagles showed up and began eating the grebes the ravens had killed.  McEneaney watched for three hours and kept track of the action.  After the ravens had killed 92 birds, they began dismantling the carcasses and flying to the shore, where they cached the grebe meat in the snow, said McEneaney, who has studied ravens for nearly 20 years. "When there's an abundance of food, they cache it," he said. "They went back and forth, back and forth."He had to leave, but when he returned at day's end, all 141 grebes were dead.  McEneaney said he has watched ravens carry off 13 baby magpies, pluck trout from a stream and even try to peck a mired bison to death, starting with its eyes. What he saw at Yellowstone Lake in May topped it all.  "I've never seen anything of this magnitude," he said. "I didn't believe they could do that much predation in one day."  McEneaney said he never considered trying to intervene. The ice was not safe, and park regulations require Mother Nature be allowed to take its course. "That's what it's all about," McEneaney said. "As gruesome as it sounds, it was really interesting to watch. It's etched in my mind."
 Copyright © 2004 Associated Press

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