A golden eagle attacking and killing a young deer were captured on camera trap set out for endngered Siberian tigers in Russia Far East. Researchers said it may be the first "documentation" of a large bird attack large mammals after decades of having only circumstantial evidence.   

The images captured showed the golden eagle clinging to the back of young sika deer, weighing 88 to 100 pounds. Its carcass was found two weeks later. The pictures were published Monday in the Journal of Raptor Research, and the authors were Linda Kerley of the Zoological Society of London and Jonathan Slaght of the Wildlife Conservation Society (WCS).

"In 11 [years] of our investigations of ungulate kills in the southern Russian Far East, this is the first time we observed evidence of a Golden Eagle killing any deer species, despite locating hundreds of carcasses during that time and assessing cause of death," the authors wrote.

"I saw the deer carcass first as I approached the trap on a routine check to switch out memory cards and change batteries, but something felt wrong about it. There were no large carnivore tracks in the snow, and it looked like the deer had been running and then just stopped and died." said lead author Dr. Linda Kerley of ZSL, who runs the camera trap project, according to a statement released on WCS. "It was only after we got back to camp that I checked the images from the camera and pieced everything together. I couldn't believe what I was seeing."

The scientists have been using camera traps for six years to monitor the Siberian tiger. They have underscore that golden eagles do not regularly attack deer, and there is no evidence that such attacks have any impact on deer populations. 

Dr. Kerley said, "I've been assessing deer causes of death in Russia for 18 years-this is the first time I've seen anything like this."