Recent news of a case of wolves doing a surplus killing in Wyoming has been all over Facebook and carried by several news outlets.
http://news.nationalgeographic.com/2016/03/160325-wolf-pack-kills-19-wolves-surplus-killing-wyoming/
I want to address a couple points of possible contention that have shown up online.
(1) Wolves don’t do this. some people say….
– Well, in fact it is a documented, though rare behavior. In 1991 there was a case of 6 wolves killing 17 Caribou at one time, I suspect the info came from this study, though that specific info wasn’t included. However they did mention the winter of 90/91 observing surplus killing. From “Wolves in the Land of Salmon” – “On February 7, 1991, in Denali National Park, six wolves killed at least 17 caribou and left many untouched. By February 12, 30–95% of each carcass had been eaten or cached, and by April 16, several had been dug up and fed upon again.
http://www.mnforsustain.org/wolf_mech_etal_patterns_of_prey_selection_in_denali.htm
And commentary from Doug Smith, the Yellowstone Wolf guru:
The point arises that, even though it is rare it does happen. In most cases environmental issues play a role in allowing wolves to surplus kill. Face it, elk or any other prey animal do not tend to wait around while members of the herd fall to a predator. In most cases of wild animals suffering from a surplus killing, the weather has produced deep snow which blocks flight form the predators. In this case we do not know the full story, was there deep snow, were fences around the feedlot blocking flight, was there some other issue? 17 of the 19 killed were young animals that may have had more issues in getting away.
(2) Wolves only kill sick or weak.
Somewhat true. Wolves kill what they CAN kill, clearly a sick or weak animal is easier prey and less likely to cause harm to members of the Pack, however, if given the chance, wolves will gladly take down a perfectly healthy animal in its prime.
(3) Feedlots?
Feedlots have been used in the West to help Elk (and sometimes other animals) make it through the winter. It isn’t natural but the logic behind feedlots is that it helps compensate for our destruction of habitat and also helps to ARTIFICIALLY increase prey numbers for the hunting industry. (please note, I am not anti ethical hunting, I’m very much anti Trophy killing and killing for fun) Feedlots also have the effects of causing Elk to not behave naturally, in that they all stand around together in a large herd in the open, and feedlots also have been well documented as locations where diseases spread.
http://www.brucesmithwildlife.com/pdf/Elk%20Winter%20Feeding%20Disease%20Facilitation.pdf
Josh Able
Bobs Creek Photos