Apparently we have yet another study soon to be released that is supposed to show that older wolves (beyond 3 years) lose their ability to be good killers and therefore this is somehow to show us that wolves are not having any affect on elk herds.
Without having the complete study, there is no way to actually make serious comment about the results of that study but the information that is being put out through press releases, I find leaves a lot of unanswered questions.
From the Science Daily:
The finding challenges a long-held belief that wolves are successful predators for their entire adult lives. It now appears that like human athletes, they are only at the top of their game for about 25 percent of that time. It also shows that physiology can limit predation.
Dan MacNulty, a postdoctoral researcher in the College of Biological Sciences’ Department of Ecology, Evolution and Behavior, says that when the older wolves lose their “edge” to be the real killers, it is left up to the younger wolves. He says the younger wolves kill for the older ones. He concludes that “physiology can limit predation”. Meaning the older wolves will kill less than the younger. It seems the professor should have also concluded that younger wolves kill more than older and make up the difference.
Wolves, regardless of age, have to eat. If, as MacNulty points out the younger wolves kill so the older ones can eat, then is there really any difference in how much killing is done? All I can see is that if older wolves killed as much as the younger ones, then possibly there would be more killing than what we have. Somehow isn’t MacNulty trying to tell us wolves are somehow trending toward killing fewer elk? How can he do that?
Nothing that I have read so far mentions anything about surplus killing by wolves. Most wolf lovers deny that wolves kill far more than they eat and those willing to admit it say it is a negligible amount and nothing we should be concerned with.
The facts are still on the ground. Wolves kill to eat and for sport. To make the claim that wolves are not having an impact on elk herds runs contrary to what some state’s fish and game biologists are now discovering. As a matter of fact in Idaho’s Lolo region, some areas have been hit so hard by wolves, elk herds have reached non sustainable levels. Is this because there are more younger wolves than older?
In Yellowstone, wolves, who hunt in packs, depend on elk for survival. The finding is timely because the park’s elk population is shrinking and wolves are being blamed. Wolves were hunted out of the area in the 1930s and re-introduced in 1995. But the study shows there isn’t a strong correlation between the number of wolves in the park and the number of elk killed.
I guess we’ll have to wait and read the report in order to figure out how the results of this study shows a lack of correlation. It’s absurd to think that the number of wolves in an area will not have a “strong correlation” in how many elk get killed. Wolves eat elk. It’s their favorite food. If there are more wolf mouths to feed, something more has to be killed to feed the hungry wolves. I would call that a direct correlation.
MacNulty further goes on to say that he thinks that predation on elk is dependent upon the age structure of the wolf packs.
MacNulty says that number fluctuates based on the age structure of the wolf population at any given time. The higher the proportion of wolves over age three, the lower the rate at which they kill elk
Unless MacNulty is willing to admit that surplus killing is an integral part of wolf behavior, I fail to see how age structure and which wolves do the killing for the pack have any significant difference in the amount of killing done. One can assume that the older wolves, presumably less active, may require less food to eat to survive but is that so significant that it seriously reduces the number of elk wolves kill?
MacNulty says hunting won’t put the species at risk, but it actually skews the population towards younger wolves, which could mean more deaths, not fewer, for the elk.
I find this statement highly questionable. What possibly can MacNulty be basing this finding on? Did his study include trips to areas in Alaska, or elsewhere, where hunting and trapping of wolves has been ongoing and has studied the effects of age structure on wolves over long periods of time where there is hunting of wolves? This is the first year in decades any hunting of wolves has taken place. Surely we cannot make any scientific conclusions about the changing of age structures of wolf packs after only a few days of wolf hunting. For MacNulty to make this claim, is he saying that mostly the older wolves are those that end up being killed via hunting? Where’s the proof?
I have no idea at what age wolves are at their prime as pertaining to killing machines. Wolves still kill and wolves still need to eat. The facts are on the ground and we see the results of their actions. Does it really matter? If biologists like MacNulty are willing to admit to significant surplus killing by wolves, then I can see how, if his findings about what age wolves are the best killers, that a young wolf pack can do a lot of killing and an older one somewhat less.