A camera trap set out for endangered Siberian (Amur) tigers in the Russian… (Linda Kerley / Zoological…)
Biologists have released remarkable photographs of a golden eagle attacking a deer in far eastern Russia after a remote digital camera designed to shoot wandering tigers accidentally captured the beasts' mortal struggle.
The images, which were published recently in the Journal of Raptor Research and by the Wildlife Conservation Society, are the first documented photographs of a golden eagle preying upon a sika deer. Up until now, it was a matter of debate whether or not the raptors preyed upon the medium-sized Asian deer.
"I've been assessing deer causes of death in Russia for 18 years—this is the first time I've seen anything like this," said wildlife biologist Linda Kerley of the London Zoological Society. Kerley authored a paper on the find with her colleague, Jonathan Slaght, a conservation biologist with the WCS.
The pair had been conducting research into Siberian, or Amur, tigers in the Lazovskii State Nature Reserve in Primorye, in the southern Russian Far East, and had used a collection of digital cameras to record the animals' movements. The camera's passive infrared sensors are triggered by heat and movement from the massive cats.
When Kerley went to retrieve the memory card from one of the cameras, which had been placed in an old old power line clearing, the biologist noticed a mutilated deer carcass in the snow.
"Something felt wrong about it," Kerley said in a prepared statement. "There were no large carnivore tracks in the snow, and it looked like the deer had been running and then just stopped and died."
When she returned to camp and reviewed the images, it was immediately clear what had happened.
Three images dated Dec. 1, 2011, revealed an adult golden eagle clinging to the back of a collapsing 6- to 7-month-old sika deer near a stand of birch and alder trees. The images were taken over a period of two seconds.
"I couldn't believe what I was seeing," Kerley said.
The biologists said they did not think the eagles routinely preyed on sika deer, and therefore weren't reducing the deer population.
However, golden eagles were known to attack a wide variety of prey, Slaght said.
"From things as small as rabbits -- their regular prey -- to coyote and deer, and even one record in 2004 of an eagle taking a brown bear cub," Slaght said.