Wolf eating habits in Yellowstone 2002

[elkaholic]

This is from the USFWS weekly report on wolves in the 3 state area. Don't see any squirrels or rabbits on here????

Predation summary from the early winter study-

This summary is from the latest USFWS gray wolf status report: "The Druid pack (8 wolves) killed a bison and 10 elk. The Geode pack (8 wolves) made 9 elk kills. The Leopold pack (15 wolves) made 10 elk kills. The elk kills were equally split between bulls, cows, and calves. The overall kill rate was typical of the early winter study (10 ungulates per pack for the 30 day period), but the percentage of bulls killed this fall was higher than normal." A conversation with Dr. Smith indicated that the increase in the number of bull elk was, relatively speaking, of exceptional magnitude.

Nine observers were in the field watch the wolf packs as well as aerial observation.

[MarlinMark]

Isn't there an "exceptional" amount of bulls in Yellowstone?

Mark

Not for long :depressed:

[Tilla]

Wolf eating habits?
I thought this would be about whether a Merlot or Pinot Gris would go with this tablefare.

[birdhunter]

Wow, wolves eat meat. Have we resorted to cut and paste to prove our points? If so let's emphasize this part:

"The elk kills were equally split between bulls, cows, and calves. The overall kill rate was typical of the early winter study (10 ungulates per pack for the 30 day period), but the percentage of bulls killed this fall was higher than normal."

Wolves are not wiping out the elk in Yellowstone, nor are they having a serious effect on the percentage of bulls in the population. All this study showed was that instead of the typical annual diet percentage of 20-21% of wolf elk kills being bulls, the number shifted to a "staggering" 33%. For this study, in which 29 elk were killed by 31 wolves in a months time, that means 10 bulls were killed, as opposed to a "normal" ratio of 6.

The only thing exceptional about the number of bulls killed is that it is slightly higher than the herd composition. Yellowstone elk herds are comprised of 24% bulls, 60% cows, and 16% calves. Typical demographics of elk in the Yellowstone wolves diet has been 40% calves, 30-35% cows and 20-21% bulls. It is important to remember that those are annual averages. At certain times of the year the demographics of wolf predation are going to shift due to a variety of biological and environmental factors.

Should it surprise anyone that the early winter predation rate of wolves upon bull elk shows a slight upward shift? Bull elk expend the most energy during the rut and are likely to be in the worst shape coming into winter. Wolves prey upon the animals that are the easiest to chase down and catch. There are no guarentees that the animals the wolves killed would have made it through the winter in the first place. This is the concept of additive v. compensatory mortality. I would suggest that many of these bulls were probably in poor shape and would have died during the winter anyways. This is a hard thing to prove and without being able to see the marrow in the long bones of the animals I can't say for certain.

I had the pleasure of meeting Dr. Doug Smith in October and we talked at length about this issue and his studies in YNP. Some of his previous studies on late winter wolf predation show an even more interesting shift. In early winter the kill rate is approximately 1 elk every 15 days per wolf. In late winter that number increased to 1 elk every 10 days per wolf. However, in late winter the number of bulls killed by wolves dropped to 0. Apparently by this time they had culled out all the weak bulls.

Can you tell me exactly who suggested that wolves only eat squirrels or rabbits? Wolves are an apex predator that feed on large ungulates. Wolves kill deer, elk, moose, antelope, sheep and bison. This shouldn't be a surprise to anyone.

You want some real information on wolves, here are a few web sites:

2001 annual report
USFWS wolf home page

11/30-12/16 report

[Gun Rod Bow]

The "let's keep bringing more predators in" crowd should take a few minutes to ponder this.

If a pack (8-10) wolves eat an average of 10 elk per month. And, assuming the age old adage of hunter success is about 10% on elk. The wolves are consuming approximately the equal of 1200 tag buying, tax paying, resource supporting consantly maligned hunters. Sport hunters are an absolutle necessity for wildlife management. No one else has ever come up with the money to purchase lands, and support the resource at the level hunters have.

There is no free lunch. I think most hunters aren't afraid of having bears, cougars, wolves, etc. The problem comes when these predators are not kept in close check.

Wolves are cool to see, in a park like Yellowstone where there is no hunting. That's a good place for them. What will we do in Oregon WHEN they cross the Snake River and start making huge impacts on elk in Oregon?

GRB

[elkaholic]

If everyone was honest and knowledgable about what is already known and the decisions are made accordingly then so be it.

I went and listened to some of the perspectives of people and they think that they are just a large coyote, wrong. They thought that if you just used llama's, the sheep would be safe, wrong, wolves are killing llamas in Montana consistently. People think there is no human threat, well there are many human/wolf "encounters" but few deaths, still there is a possible encounter, otherwise why would ODFW put all the tips to keep from having a bad experience if there was no threat, there is, small as it is people need to know that.

And yes they do kill livestock and pets. Most pets are canines. Livestock, well I suppose if the real goal is to not "bait" wolves, then you must not tempt the wolf by having or running them in the open. People only talk about the losses, those costs are low compared to the time responsible livestock producers spend trying to not have a loss. It is a "cost".

Just some thoughts. :smile:

[TheRogue]

Speaking specifically for the Yellowstone aspect, well, good for the wolves. Hunters are not allowed to harvest the animals to keep the herd at manageable levels.....the area is normally WAY over carrying capacity for it's elk herd, and must be fed in the winter. Otherwise, there'll be another tremendous outcry from the animal-huggers about the starving elk.

BH is right, it only makes sense that the predation is heavier on the bulls right now.

Still, though, I am against wolf re-introduction in Oregon right now, natural from the "swimmers" or by planting. I like GunRodBow's anology. NE Oregon elk have some problems already, and taking away tags and the $$ they produce doesn't make much sense to me.

TR

[WildHawg]

Birdhunter,
as usual, I am impressed with your analytical and writing skills. I appreciate your take, as I think any person who is truly interested in the issue, whether pro or anti wolf, should.
It is a very deep and emotional issue, which I am confident can never be resolved to the satisfaction of those on either the far right, or far left. Wolves are native. They will repopulate areas with adequate food. They will, if they already have not--return to Oregon.
Leave 'em be, 'til they perpetuate all the myths many of you like to propogate. If it gets as bad as some of you say it will, I'll be the first one to thin the buggers out. Until then, I'm waiting to hear a wolf call to its pack in the Eagle Caps. You cannot possibly have a heart if you think that sound, which was indigenous for many millenia throughout Oregon and the west, would not make the mountains, and this "enviro freak" smile bigger than we have in years :grin:
HOWWWWOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[skein]

Wildhawg and Birdhunter,

I believe wolves without management will be a disaster. It will be a disaster for the big game population and a disaster for the hunter and enviro-freak (as you put it).

If it gets as bad as some of you say it will, I'll be the first one to thin the buggers out.

<font size="2" face="verdana,arial,helv">No, Wildhawg, you won't, because you will be banned from doing so. No one will be allowed to hunt/thin/manage them. There will be no management plan in place as they swim across the river, and none will be put in place until it's too late - and that plan will be governed by emotion, not science. People from the city WHO HAVE NO VESTED INTEREST IN THE WOLF-POPULATED AREAS will determine those "strategies" though an initiative on the ballot. You will also lose out on the chance to see or hear them, because huge areas of land will be barred from public access because of an "establishing" pack or "denning" pair.

Put me down as one who is firmly in the "No wolves without a management plan in place" camp. Until that has been agreed upon - No Wolves!

Birdhunter, you know that I've been studying this issue, reading, talking to people, listening, and I've been slow to reach this decision. I haven't studied them like you have, but I have weighed both sides carefully. We're not ready for wolves.

Skein

[Norm]

Interesting data, I would have thought ungulates would be a much smaller part of the wolves diet. Ten elk per pack seems like a lot to me. I would still be interested in seeing a 12 month survey of a packs diet. Is there a shift in spring/summer to smaller pray? When I was in Northern Alberta, the moose guides seem to think most of the moose killed by wolves were in the winter months. I had a wolf tag, but never filled it. I think there is still room in Oregon for a few packs, Just not too many .