Grizzly Bears in the North Cascades:
A Population on the Edge of Extinction.Excerpted from the Environmental Review Volume One Number Ten October 1994
In 1975 the grizzly bear (Ursus horribilis) was declared an endangered species in Montana, Wyoming, Idaho and Washington. The Endangered Species Act requires federal agencies to protect and to recover existing grizzly bear populations. Federal and state officials have formed the Interagency Grizzly Bear Committee (IGBC) to coordinate bear conservation and recovery activities.
William Gaines has been a wildlife biologist with the U.S. Forest Service for ten years and is based in Leavenworth, Washington. He has an M.S. in wildlife biology from Central Washington State University and has worked on the grizzly bear recovery project since 1987.
ER: Bill, how did you get started on the grizzly project?
WG: I started on the grizzly bear recovery project in 1987. Initially I was doing field work, then in 1988 I became the mapping coordinator responsible for producing a vegetation map of grizzly bear habitat in the North Cascades. [in northcentral Washington State. ed.] When the initial grizzly bear recovery plan was written in 1982, the IGBC identified some of the areas;such as Yellowstone and North Continental Divide, where they knew they had some bears and they designated them as recovery areas and they set up objectives for recovery.
ER: This was in response to the Endangered Species Act?
WG: Right. The grizzly bear was listed as endangered. So under the Endangered Species Act the committee developed a recovery plan that outlined the steps necessary to remove the bear from the list - to recover bear habitat and recover population levels.
When the first recovery plan came out in 1982, four ecosystems were identified as recovery areas: Yellowstone, Northern Continental Divide, the Cabinet-Yaak area on the Idaho/Montana border and the Selkirk mountains in northern Idaho. There were two additional areas, the North Cascades in Washington and the Bitterroots in Idaho, that were designated evaluation areas. They were not immediately designated recovery zones because we did not have good information on the habitat available to bears, what level of human use was taking place in those areas, and what were the bear populations there. We knew there were historically bears in the North Cascades, but we did not know what the current population was.
In 1985 the IGBC outlined a study plan for those two evaluation areas. They needed information to make a decision on the bears. So in 1986 we initiated the study here in the North Cascades.
Our objectives were to determine the current population of grizzly bears and to produce a map showing the vegetation available, the diversity of bear foods, and to overlay that with what human activities are taking place. The questions were, how much habitat is available for bears and does it warrant attempting recovery here in the Cascades?
ER: What are the boundaries of the North Cascades ecosystem?
WG: Its northern boundary is the Canadian border. On the west side it is the west boundary of the Mount Baker/Snoqualmie National Forest.
ER: So the ecosystem extends down the west slope of the Cascades out of the high country?
WG: Yes, it does. And then the I-90 corridor across the south border and the Columbia River up to the confluence of the Okanogan River to Canada makes the eastern boundary. [Interstate 90 is 150 miles south of the Canadian border. ed.] And in Canada we have another good chunk of habitat that extends along the North Cascades crest up into Canada.
ER: Do you feel bears are being given a fair chance? It seems like we are putting pretty strict limits on available habitat before we allow grizzly bears to recover. Is that accurate or am I jumping to conclusions?
WG: I think there is some legitimacy in what you are saying. Even to become listed as an evaluation area, the IGBC was looking for two criteria. One was that there is a core wilderness area, a security habitat for the bears, that is surrounded by other more multiple use areas which also provide bear habitats. But that core area is very important to the survival of the bears.
A second criteria was some indication there had been historic bear populations, and possibly still some bears around. That did not pan out in the Bitterroots. [The Bitterroot mountains are in south-east Idaho. ed.] They have not confirmed any bears in the last twenty years there, whereas in the North Cascades we have. And yes, there are many other areas throughout the bears' historic range, but with chunks of wilderness core, there is not a lot of that left.
ER: What was the grizzly bears' range before they were hunted out?
WG: Historically, their range was all of the western states down to central Mexico. Grizzlies were wide ranging west of the Mississippi and were adapted to a variety of different habitats including the plains bears. Their estimated population historically, it is difficult to estimate, but it was as high as 100,000 bears. We are now at about two percent of their former range in the lower forty-eight states and fewer than 1,000 bears.
ER: How many grizzlies are in the North Cascades?
WG: From records from the Hudson Bay forts and trapping companies in the Cascades we know that there was historically a fairly large population of bears here. In the mid 1800s, in a period of about five years, there were 450 bear pelts processed through those forts. That indicates we had a pretty good population at one point. Extensive trapping, extensive predator control efforts and encroachment on habitat all resulted in the situation we have today. What all the research since 1986 has boiled down to is there were twenty-two class one bear observations. Class one is the most highly reliable observation you can have.
ER: Short of finding a carcass.
WG: Right. And a carcass can also be a class one observation. Class one tells you it is almost certain that you have seen a grizzly bear. One of the class one observations was a sow with cubs. It was very far south in the ecosystem, indicating that bears were resident. There was some discussion initially that maybe bears were just moving into the Cascades for the summer and moving back to Canada. That they did not reside here, which probably is true to a certain degree, but we believe that they were resident.
ER: Where was the sow and cubs seen?
WG: It was in the Cle Elum area at the very southern extension of the study area. We have had sightings all across the area. So we have a well distributed population that appears to be reproducing. And we came up with an estimate of ten to twenty bears. That estimate is based upon professional judgement but also upon the sighting information. We have those twenty-two confirmed grizzly sightings but we had a total of 238 observations that were followed up on.
ER: Those 238 were not confirmed grizzly sightings?
WG: No. Twenty-two were confirmed and the rest were class twos, which are still good sightings, or class threes. If there was any question about a bear sighting, we were conservative and called it a two or a three.
ER: The point is, your estimate of ten to twenty grizzly bears is a conservative estimate.
WG: It is based upon as realistic, objective and scientific approach as we could take. I would not want to lead you to believe that the population could be more because I feel that our grizzly bear population is in pretty dire straits.
ER: Are the North Cascades grizzlies a remnant population or are they moving down from Canada?
WG: It is difficult to say, but probably they are a remnant from a larger population. There is not a big population adjacent to us in British Columbia. The Cascades ecosystem extends into British Columbia, and there is a small population of perhaps the same size in B.C. that is connected to this one. There is some movement across the border, certainly, but from our information it appears as though we have a small resident number. And we work cooperatively with British Columbia to have consistent management across the border.
ER: I'm surprised that there isn't a bigger population in Canada. I was hoping they could help us out.
WG: Right. That was our hope. It certainly helps the gene pool by doubling your population there. In Canada they have a little more active bear program where they are moving bears around in ecosystems. That helps to a certain degree. It can buy some time for them.
ER: Does the IGBC recovery plan call for moving bears into the North Cascades from other areas?
WG: When you have a population as small as this, and when you couple that with the reproductive biology of bears, they do not produce a lot of young over the course of their lifetime, a small population will have problems with inbreeding. Using computer modeling and population statistics, we think a population of ten to twenty bears is very likely in a downward trend. Based on the biology, we need to inject some fresh genetic material into this population.
Moving or augmenting a population of grizzly bears in the North Cascades is a very emotional issue, and it tends to be what people focus on over and above habitat improvement and bear-safe camping. But we tend to get focused back on that population augmentation issue.
In order to move any bears into the Cascades, it is required under the Endangered Species Act that we do an environmental assessment or environmental impact statement where we will look at different alternatives to augmenting bear populations. And there is a variety of alternatives from cross fostering with black bears, to bringing bears in, to not doing anything. A whole range of alternatives will be considered.
That process is fully open to the public for comment. It will spell out the biology and the consequences of each of those alternatives and that is very important. It is important because it is very difficult to succeed at rebuilding a population of grizzly bears if you do not have some level of public support. And when you have a bear population that is in such a precarious position as we have in the North Cascades, any loss to that population is very significant. We need to minimize that.
It is a delicate balancing act between knowing we do need to do something for these bears and educating people and bringing them along so they understand what augmentation is all about. When you say augmentation, many people have this image of a flatbed truck pulling in with 200 bears and dumping them off at every trailhead. When I can sit down with people one on one or in a small group and explain what an augmentation program probably would look like, it tends to alleviate those fears. I explain that there are not too many bears anywhere that people are willing to give us. So it is not going to be very many bears. We are going to be lucky if we can get five over the course of ten years.
ER: Is that enough to reduce inbreeding?
WG: We do not know. We are going to have to monitor it and see how the population responds. But if you can add one bear per generation, that tends to help their genetic situation tremendously. And we would try to pick young females with a lot of breeding years left. Females tend to roam less so they are better candidates for bringing into strange areas.
We would want to pick bears from similar habitats so the likely scenario would be from Canada. In Montana they have moved three bears, after extensive public input and public agreement on how many and where. They radio collared the bears and every so often the local newspapers have a little blurb on what the bear is doing and where it is, just to let people know. We can radio collar the bears also.
We would only bring in bears that have no history of being in trouble - no garbage bears. And once you sit down and explain to this people a lot of their fears about it are relieved. We need to have time to educate the public, and at the same time to be moving along on with this environmental assessment process. That is the scenario after we get the recovery chapter approved.
ER: People who run livestock on the east side of the Cascades have a different set of concerns than the backpackers in the high country.
WG: The livestock folks have, of course, their livelihood and their business. Being able to graze on public lands and the predation factor are fears we need to address. We need to provide good information to ranchers because the dangers are largely overstated. Bears hardly ever bother cows. They will bother sheep if you do not follow the right procedures, but a lot of sheep grazing goes on with grizzly bears around. Also, we can set up a method to compensate people for losses like they have in Montana.
The hiking community has a different set of concerns. One is that there will be closures of trails and they will not be able to get to their favorite place. And certainly there can be closures. If a sow and cub are feeding in a berry field along a trail, for safely reasons as well as allowing the bears freedom from disturbance, we may close a trail while the bears are in there. But bears are not going to stay there all summer. So the closures will be spotty.
The other issue, and probably all groups share that, is the safety of having bears around. That is legitimate but again, you need to temper that concern with information about proven methods to reduce your risks. And the risk of a bear confrontation is quite low. It is very dramatic and emotional when something does happen, but the risk is not that great that it will. There are many precautions you take with grizzly bears that you should be taking with black bears as well, and we have a number of black bears in the North Cascades. So we are trying to educate people about bear-safe camping practices: taking care of food and not putting food in your tent, and we should be doing that for black bears too.
ER: When grizzlies come out of their winter den and there is still snow on the ground, what do they eat? [Grizzlies den at high elevations. ed.]
WG: The bears come out of their den sometime in April. Usually the males will come out first and the females come out somewhat later. One to four cubs are born in the den ,usually in January or February; most commonly twins are born. After grizzlies come out of their den they spend a little time around the den site. Then most often they head down to lower elevations where the snow has receded and there is fresh green vegetation. These are areas where winter-kill deer and elk carcasses are often available. And there are grasses and forbs that have come up in the springtime. [Forbs are herbaceous plants other than grasses. ed.] The low elevation forests are also where breeding usually takes place.
ER: Grizzly bears eat grass?
WG: Yes. Grasses and forbs. They are largely vegetarian. And they are opportunistic, they will take deer or most often fawns and calves of elk, but ninety percent of their diet is vegetation.
Now the spring areas are important habitat for bears, especially here in the Cascades. Many of our low elevation river valleys, good breeding areas, good spring habitat, are also where people live. The bear/human interaction is important to the survival of the bears.
ER: They go back to the high country in the fall?
WG: Yes. Through the course of the late spring and early summer, they move up into high elevations. Some of their important habitat components are avalanche chutes and small wetlands. They move up following the snowline. Right behind the snow the soil is moist and avalanche lilies and spring beauties, the early season forbs - pop up and the bears will pick those right after the snow melts.
ER: Is that why bears like avalanche chutes?
WG: Right. The disturbance of the snow slides tends to keep those grasses and forbs available to them. After the breeding takes place in May and June, the male grizzly takes off and is pretty much on its own. Males tend to roam over several hundred square miles. The size of their home range depends on the quality of the habitat. The average home range for female grizzlies in the lower forty-eight states is about seventy square miles. Within that home range, they are able to find all of the foods, all of the security habitat, everything they need to survive throughout the year.
In later spring and early summer, grizzlies get up pretty high in the mountains. Then in later summer when the berries come on, berry fields become an important habitat for food. Later summer and early fall is an important time of the year when bears will consume massive quantities of food. They key into berries and the fall salmon runs, anything where they can get a concentrated food source because they are putting weight on for the winter.
Grizzlies do not put on that much weight in the springtime recovering from their denning period. That does not occur until later on in summer. So it is important that they put their fat reserves back on for the approaching winter. Grizzlies become pretty opportunistic after the berries have dried up. Sometimes in September/October they will move back down into the lower elevations where there is green vegetation to feed on. Then depending upon the weather, they will den sometime in November.
ER: Do the males den also?
WG: Yes. And males tend to den a little later than the sow and cubs. Bears are one of those species that invest a lot of time and effort in teaching and raising their young. Typically females are not able to reproduce until they are four or five years old, and then they come into estrus only once every three years.
ER: How long do they live?
WG: The oldest bear we know of is thirty-five, but probably twenty to twenty-five is more common.
ER: So they will get a chance to breed only four or five times in their life?
WG: Yes. And maybe not that much because as they get older they are less able to. So maybe three or four shots at it; grizzlies have a pretty low reproductive capacity. The young will stay with mom for two or three years. She teaches them everything they need to know about the area where they live, where to find the food.
She can also pass on some strategies that can get them in trouble. And that can be devastating because usually if mom is in trouble, then the kids are in trouble. And if you have to do something with them, you wind up having to do it with the whole family group.
ER: You mean when mom teaches them to break into cars or garbage cans?
WG: Exactly. She is passing on that learned behavior to the cubs.
ER: The path of least resistance would be to do nothing. How long would it take this population to die out if we do nothing?
WG: We pulled in information from other bear populations to try to get that estimate and it is not a pretty picture. For a population of ten bears, the average time until they go extinct is about fifty years. Using computer simulations, all the grizzlies were gone within one hundred years. Using a beginning population estimate of twenty bears, all bears are gone within a couple hundred years, and the population is in a downward trend in every case. This north cascades grizzly population is remnant and it has been that way for awhile. Our best information suggests that the population is going down. How much time the bears have, I cannot tell you.
ER: Has the establishment of wilderness areas in the North Cascades slowed the decline of the grizzly population?
WG: It has to a certain degree. When we did our habitat evaluation we discovered that there is not a lot of lower elevation spring habitat within wilderness areas. The wilderness boundaries are pretty much drawn around the high country. We have identified where we think grizzly habitat is and we are going to have to do further research on the bears and radio collar them and let them tell us where they are.
But we are still going to have to manage how much human access we allow in there, making sure that our campgrounds have bear-resistant facilities so that if bears get in there it is as safe as we can make it for them.
We cannot rely on the wilderness for grizzly habitat. We have to look outside the wilderness. When we drew lines around the recovery zone we could have drawn a line just around the wilderness core and it probably would have had a lot less controversy surrounding it. But because of the way the Cascade Mountains are oriented, the low elevation spring habitat sits on the periphery of that ecosystem. And that pushed our lines east and west outside the wilderness to pick up some of that key habitat.
ER: What is good spring habitat for grizzlies?
WG: Ideally, we would have radio telemetry and food habits information from this local population. We do not, so we pulled in information from other areas. We had to be cautious about drawing conclusions because other ecosystems are very different. The east side of the Cascades is similar to the Rockies but the west side is more similar to coastal British Columbia.
Bears are generalists; they use a lot of different vegetation types. When we mapped the vegetation we identified all the plant species within the area and how abundant they were. Then we did an extensive literature search on food habits of grizzly bears outside of Alaska to determine what kind of plants constitute bear foods. In the springtime they eat early season grasses and forbs...
ER: Avalanche lily bulbs?
WG: Yes. Avalanche lily bulbs, spring beauties, the little flowers that have onion-like tubers. And in the springtime they are also feeding on some of the winter-kill carcasses. And that continues until the berry season in the fall. In the Cascades we have seven different kinds of huckleberry. We also have serviceberry, gooseberry, currant, many berry-producing shrubs and those shrub fruits are important into the fall. There is a variety of other foods they feed on opportunistically: skunk cabbage, horsetails - an extensive list.
ER: Horsetails? It must be the roots.
WG: Yes. They dig out the roots. We came up with a list of about 120 plant species that were bear foods. And here in the North Cascades we have one hundred of those plant species. Partly due just to the east/west diversity of this ecosystem, the wet west side and the dry east side, we have a great diversity of foods.
ER: What are the main threats to grizzly habitat?
WG: Probably the biggest issue dealing with bears and bear recovery tend to do with mortality. Not so much that you convert their habitat, say for logging. That is still an issue but it takes a back seat to human access. By human access I mean accessing security areas for bears. That human\bear contact can result in illegal killing. That is a big issue. It includes misidentification,confusion with black bears, hound hunting and bear baiting, all those can lead to grizzly bear mortality.
There are two main ways we attempt to manage security: one is education, but two is by looking at how dense our roads are and how much human access there is. Because of their low reproductive capacity, losing one animal is a big deal.
Additionally, with the human access issue, it is not just illegal or misidentified killing, it is putting people and bears in a situation where there can be a conflict. And there the tactic we need to take is education and cleaning up our garbage. We need to deal with those sources of direct bear mortality. If we are going to recover a population here we need to create a safe environment for them.
ER: That means reducing human contact?
WG: It is a combination of managing human access at a tolerable level. We have some pretty good information about how many roads are too many - a mile of road per one or two square miles. Managing human access means timing it in relation to when bears would use the area, and then educating people on how to identify bears and what to do about their camping practices.
ER: How many grizzlies would be expected to live in the North Cascades?
WG: Our best estimate is that the ecosystem could support a population between 200 and 400 bears. That number is constantly changing and it tends to be increasing, to be frank. But we are going to have to monitor that population as we proceed with recovery: number of sows with cubs, what percentage of the area is occupied, how distributed are those populations? It is difficult to get an absolute number. You cannot do that with bears because there is no way to census them.
ER: That estimate comes from what you know about other ecosystems like Glacier and Yellowstone?
WG: Exactly. We looked at bear densities in other areas and looked at the similarities and differences in the habitats here in the Cascades.
I certainly do not want to paint an image that when bears and people mix there is always conflict because there are many examples in Yellowstone and Glacier National Park where we have a lot of recreation and we have a lot of people, and the grizzly bear is a big draw to those areas.
Through education and helping people learn about grizzly bears, I think we can live in relative harmony with that spectacular animal. We have a challenge here in the North Cascades because we have a large human population center next to a recovery zone, and that makes this ecosystem unique. [Everett and Seattle are less than one hour from the western boundary of the recovery area. ed.] But it puts very high emphasis on the educational aspect of recovery. It is possible to live with and enjoy this animal. I think that is an important message.
Copyright 1994 Environmental Review