Imagine wandering out to check your camera in the remote Far East of Russia, and finding the hide and skeleton of a sika deer, picked clean by something. In a region stalked by tigers and bears, the death of a deer would at first seem not unusual. But this deer has no tiger prints, nor bear prints, not a trace of any predator to explain the what appears to be sudden death.
This mystery could only be solved because the entire event was captured by the camera trap set up to monitor tigers and leopards by biologist Dr. Linda Kerley and wildlife vet Dr. Misha Goncharuk.
From the Wildlife Conservation Society press release:
"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. "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."
Co-author Dr. Jonathan Slaght of WCS noted that golden eagles have a long history of eyebrow-raising predation attempts. “The scientific literature is full of references to golden eagle attacks on different animals from around the world, 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.”
The eagle does not succeed to lift off with the 6-7 month old deer, weighing approximately 40-50 kg. But the tracks in the snow tell the further story of what transpired off camera: the deer collapsed about 7 meters away and died from the wounds it received in the attack. The camera subsequently caught images of a cinereous vulture, 2.3 hours after the attack, joined by more vultures, at least one large-billed crow, and a red fox over the next 10 hours, as nature made the most out of one deer's tragic end.
The photos establish a scientific first. In their paper First documented predations of a sika deer by golden eagle in Russian Far East, published in the Journal of Raptor Research, the authors note that before this photo, it was not believed that golden eagles preyed on sika deer:
Bromley (1956) specifically stated that Golden Eagles do not prey upon sika deer in Russia, an assertion based on the assumption that these eagles would only take newborn fawns (which are birthed in impenetrably dense understory), and Uno and Kaji (2006) wrote that brown bears were the sole natural predators of sika deer in Hokkaido, Japan.
Thanks to the amazing record from Linda Kerley's camera trap, now we know better.