The annual count of elk on Yellowstone’s northern range is in. It remains low compared to years past, but is about the same as a year ago — 6,738 elk compared to about 6600 in the last count, 9 months ago.
The Northern Range herd has always been controversial with its numbers called wildly excessive in the past. It reached at record high of 19,359 in late 1993. It was 17,290 in late 1994. Wolves were reintroduced 3 months later. Then, unfortunately were no elk counts until Dec. 1997 when the population was 13,400. It was known there was a great winter die-off in Jan-March 1997, but there no count made in 1996 or spring of 1997. Since then the population has had its ups and downs, but mostly downs, to the present.
By late 1997 critics had changed from saying the herd was excessively large to alarmed critics saying that wolves were killing off the herd. Some of the decline in the period 2000-2005 has been blamed on a multi-year drought. It is also pretty clear that predators are keeping the herd down in size
The herd has a greater variety of predators that any in the lower 48 states: grizzly bears, black bears, wolves, cougar, coyotes, humans (there is a hunt outside the Park), and the herd is not just a Park herd, despite the name. One elk was even killed by a wolverine. A 3-year study showed the major predator of elk calves in the herd was grizzly bears.
This is one herd probably limited by predation. The size of the human take was been reduced greatly in recent years by Montana Fish, Wildlife and Parks.
Here is the story by Mike Stark from the Billings Gazette.
This northern range herd is one of 8 elk herds that use Yellowstone Park. Some people seem unaware of this.
Comments
This story on the Northern Herd got the usual bombast of thoughtless comments in the Billings Gazette. What is not clear to me is how excessive the issue of late season cow-calf tags has been over the years. This story says there will be a reduction of such tags. This is an important statistic that needs to be cleared up.
There has been a decrease in tags from 2800 to 100 last year. Don’t know about this year if any.
Dora–Thank you for this information. Does FWP publish annual herd unit reports? I’m sure FWP does publish such reports. As is the case here in Wyoming, the herd unit reports should report quite a bit of information that doesn’t normally get into the press.
I myself am not yet willing to grant that predators are limiting the Northern Herd in the ecological sense, unless we include within the definition of predators human predation. Also, we do know that the Northern Herd has been a “geriatric “herd in many ways, and in the absence of other data, surely the presence of many older animals in the herd is a significant factor in its numerical decline over the last 5-6 years.
I’m kind of surprised that with all the predation the elk left are geriatric, not prime.
Of course, the heavy bear predation is of young calves (less than an month old)
As I recall, FWP put out a press release some time back about the relative old age of elk in the Northern herd. I’ll try to find it. I’m going to start researching this herd in depth anyway.
What I find when I look into different elk herds is that, well, they’re all different. This is one reason that all the broad generalizations you hear are often empty generalizations. Each herd responds to various pressures, including predation, differently, mostly in subtle ways, but still differently.
Of course there are also major differences between and among elk herds, e.g, the Southern Yellowstone Elk Herd–the Jackson Herd–is fed, whereas the Northern Herd is not, although it used to be.
The Wiggins Fork Elk Herd, my local herd, has never been fed, and one segment of that herd, the Dunoir segment, also crosses the Continental Divide in its migrations to and from summer and winter range. One interesting fact about the Dunoir segment is that it experiences heavy bear predation in the spring, since calving areas are somewhat restricted by terrain, yet it was also the Dunoir segment of the herd that bore the brunt of the recent herd reduction program that I have discussed. Also, the first wolf pack in the Upper Country set up in the Dunoir. Yet, this segment of the herd has flourished, at least till now.
As yet, we don’t know why this segment of the Herd is apparently so productive and resilient. I’d like to find out why, among other things. This is another reason why protecting the Dunoir as wilderness is so important.
I agree that every elk herd is different, and unfortunately a lot of people focus on one herd and generalize everything from a sample of one.
The reason the elk herd is geriatric from predation is the extremely low calf retention rate. The number of young elk gets proportionately lower year by year. As the numbers drop that should begin to balance to an extent and more young elk show up.
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This is a plausible hypothesis. I am not one to argue that a naturally regulated elk herd that is declining in the population size is a bad thing any more than a naturally regulated one that is increasing is bad thing or a good thing. However, I do think it is likely that in a number of instances outside national parks, where elk habitat is not the limiting factor, and where the cow:calf ratio is low, you will find that bears, more than any other predator, hold elk populations down. I have posted a number of articles to that point, results of studies. Ralph Maughan
That is what should happen. The point is, I haven’t heard this explanation from FWP. That’s another reason why looking into the Herd Unit Reports for the Northerns Herd is so important. We need to start getting the facts out because the press simply is refusing to do so.
The question is, and it’s one that I rarely see adequately addressed, is or is not habitat limiting?
Because it is difficult to quantify habitat quality or carrying capacity, I have found that most predator-prey studies write off habitat and focus on things more easily quantifiable, and this quite frankly skews the findings, especially on the topic of whether predators regulate or merely limit their prey. There is a difference between the two. The more important question is one of regulation, which refers to wolves/predators controlling theirprey in the absence of other factors. This has never been demonstrated. The most that can be demonstrated is the predators can limit their prey, depending upon the influence of other factors. However, factors such as environment and climate, which also influence habitat, have a much more fundamental influence on predator prey relationships than than we’re willing to acknowledge. And we’re missing a lot by refusing to acknowledge these more fundamental factors.
This is especially true in Alaska, something that the National Research Council assessment, Wolves Bears, and Their Prey in Alaska noted. My own research in the Yukon, which was historically based, since that’s all the information available, is that habitat fragmentation of a pristine ecosystem (i.e., The Gold Rush, the Alaska Highway) initiates fundamental changes in habitat and predator prey relationships that are both masked by time and cascade down through the decades without people realizing it. Without taking the cumulative impacts of habitat change over time into account, it is easy to assert that predators are controlling their prey simply because the time frame of the study is limited. Longitudinal studies of predator-prey-habitat relationships are virtually non-existent,except at Isle Royale, and that’s a very limited situation for a lot of reasons.
It’s also easy, and politic, to ignore climate/environmental/habitat changes. In my view, it’s more important to ask qualitative questions about habitat than about numbers (functional/numerical responses of predators to prey numbers, etc.). I am convinced of this.
I’m curious if grizzly bear predation on elk calves has increased in recent years. Considering that two major sources of grizzly food–white bark pine nuts and cutthroat trout–are in steep decline, I’m very curious if bears have begun focusing more heavily on elk calves as a protein source. Does anyone know if there have been studies of grizzly predation on elk calves prior to noticeable declines in cutthroats and white pines? Of course, grizzlies have always preyed on newborn ungulates in Yellowstone, but they may be concentrating on elk more heavily if other food sources have declined.
Howard–Off the top of my head, I know of no early studies of grizzly predation on elk calves in the Park. This is a question we should pose to Center for Natural Resources, perhaps. The studies of which I am aware are more recent; these are the ones that have been in the news. Grizzly researcher Dave Mattson has documented the heavy reliance of bears on meat from various sources in Yellowstone.
We know from studies up North that multiple predator systems do in fact see limitation of ungulate populations by predation. It is my view that we have to include hunting, however, primarily because it tends to be left out of the equation.