One of the major factors every year whether there will be grizzly conflicts in the fall is the status of fat-rich whitebark pine crop.
If there is a good crop, the bears will stay at high elevations where the whitebark pine grows — just below timberline.
In recent years, there has been some pessimism about the future of the grizzlies because whitebark pine are dying out in much of the greater Yellowstone ecosystem (GYE) due to whitebark pine blister rust (a non-native pathogen). The GYE fires of 1988 also burned high elevation stands east of the Park. However, the whitebark remain strong in some parts of the GYE, especially to the south and southeast. When Lee Mercer and I were working on “Hiking Wyoming’s Teton and Washakie Wilderness” the number of bears to the Park’s south and southeast was very impressive, especially compared to my experiences 10 to 20 years earlier.
The article today in the Billings Gazette has a headline that suggests the big crop is maybe a bad thing — “Big pine cone crop could bring in bears.” This is misleading. Yes, hunters should be careful in the high elevations, but that is a lot better than having hunger bears down among the houses and pastures in the stream valleys.
Read the Billings Gazette article.
Comments
I wonder if there is any correlation between declining white bark pine (at least in some areas), the major decline in cutthroat trout in many Park waters, and the increased bear predation on elk. Of course, correlation is not causation, and ecology is a very complex subject, but I think the idea is worth looking into.
I think whitebark pine nut availability, or lack of it, and the decline of cutthroat trout due to lake trout and whirling disease is related to bear predation on elk.
Howard,
I agree.
The number of grizzlies in the Park appears to be about stable, so if they are not getting their nutrition from nuts and fish, they must be getting it elsewhere. More grazing on grass and forbs seems unlikely, especially with the long term drought. The same is true with berries.
There was a study, can’t find it now, that indicated that Yellowstone grizzlies have become the most carnivorous of all grizzly bears (that doesn’t count Alaska and B.C. salmon-eating bears).
Grizzlies have always preyed on newborn ungulate calves, but if I understand the situation correctly, the last few years have seen grizzlies seeking out elk calves with increased determination, regularity, and longer into the spring season. Biologists have recently determined that grizzlies are by far the dominant predator on elk calves in YNP… all other carnivores combined don’t come close to matching the grizzlies’ mortality rate on baby elk. Meanwhile, many biologists have been very alarmed by the decline of white bark pine and cutthroat trout, with several predicting disaster for the great bear. I think it is possible that the decline of these highly nutritious food sources have prompted grizzlies to seek their calories elsewhere. In particular, the decline of the cutthroat, which spawns in spring and historically provided a major early season food source to bears as they made their annual upstream run, may have forced the bears to take their spring protein in the form of elk (I would be very interested in how far apart in time the cutthroat run is from the elk calving).
The Yellowstone cutthroat spawn in June and July, and elk late May and early June. The more rapidly elk “flood” the landscape with calves, the fewer the bears get to eat because a calf can outrun a grizzly or black bear by about 2 weeks.
Grizzly bears are incredibly smart, learn quickly, and have excellent memories…and when food is involved, their genius is scary. It did not take the grizzlies long to figure out how to get elk calves….that you ignore the mother elk’s distractions, and just keep circling the tall grass until you hit paydirt. That these bears, with relatively poor eyesight and perhaps the best nose in the mammal world, know and remember that the food they seek is odorless is just incredible. Furthermore, it seems that once one bear learns the trick, the others catch on very fast.
One thing you didn’t mention, and it is very important, is that grizzlies have learned that wolves mean elk carcasses. If a pack doesn’t consume an elk carcass within about a day, a grizzly usually discovers it. Mollies Pack in the Pelican Valley is facing a serious situation in this regard. The Pelican has always been a very dense area for grizzlies due to the forbs there and the cutthroat trout in Pelican Creek and its tributaries. Now that the trout are almost 100% gone due to whirling disease, the grizzlies have turned to the elk carcasses.
Multiple grizzlies follow the pack, and Doug Smith told me that recent observations show that every elk carcass is taken by one, and usually more grizzlies, within just an hour. He said he recently saw the alpha male watching while 4 grizzlies ate the elk his pack has killed. When the wolf approached, he was immediately chased off by the bears.
As a result of this, the pack has to kill more and more elk. This probably can’t continue before the pack leaves or falls apart, then the grizzlies will be at a loss for food.
This isn’t a problem for Idaho wolves, but I suspect it might be for wolves in the north central Montana grizzly country like the Bob Marshall Wilderness and Glacier National Park.
-Ralph Maughan
Again, this is thus far just a thought, but I think it’s logical and worth exploring further. It will also be interesting to see how this affects the elk population, especially if this behavior is new to the system.