Bears of Kennicott Valley

Basic Bear Ecology

In order to properly understand bears, it is necessary to understand their basic ecology. In general, bears are active for 57 months out of the year in Alaska. Most mating takes place from midMay to the end of June. Male bears may wander far during this time in search of prospective mates. Females give birth to 13 cubs in January or February while dormant in their dens. Bears are very intelligent and may live for 34 years or more. They are very good at locating and remembering nutritious food resources (including human foods and garbage). Bears are also curious creatures and rarely miss a chance to investigate novel items in their environment. This curiosity probably evolved as a foodfinding strategy. For example, if a bear finds food by investigating burn barrels or homesites, then it is likely to look for food in burn barrels and homesites in the future. Consequently, storing food, garbage, and other human attractants properly is the single most important thing you can do to prevent conflicts between bears and humans.

When subadult bears reach the age of independence (usually at 2 ½ to 3 ½ years of age), they must establish their own territories. Females can usually adopt a portion of their mother’s home range as part of their new territory, whereas newly independent males almost always leave their mother’s home range and seek out territories in new areas. These newly independent bears are inexperienced, hungry, and travel through unknown territory during this time, and are thus more prone to come into conflict with people. They seek out areas with few dominant males, good nutritional resources for the rapid attainment of large body size, and breeding opportunities. Because of its extensive soapberry (Shepherdia canadensis) habitat and human occupation, the Kennicott Valley provides all three, and is thus attractive to young male bears. These facts have direct implications for the occurrence of bearhuman conflicts in the valley.

Bears are Ruled by Their Stomachs

Because bears are dormant for 5 to 7 months of each year, they must meet their nutritional requirements in the relatively short time between den emergence in the spring and winter dormancy in the fall. When bears emerge from their dens in the spring (usually early April), there is precious little for them to eat. In the Kennicott Valley, they mostly feed on overwintered berries, horsetail (Equisetum spp.), grasses, sedges, willow catkins (Salix spp.), and balsam poplar (Populus balsamifera) buds at this time (based on studies in neighboring Kluane National Park, bears in the Kennicott Valley are probably 8596% vegetarian). If they are lucky, they may also find winterkilled carrion to feed on. Grizzly bears also dig root crops such as eskimo potato (Hedysarum alpinum) and field locoweed (Oxytropis campestris) in the early season. Because of the low nutritional value of the foods available in the spring, bears continue to lose weight for a month or more after den emergence. When berry crops such as soapberry ripen in late July, bears abruptly switch to feeding on them. Some bears, particularly grizzly bears, may also migrate to salmon spawning areas.

Bears evolved from carnivorous ancestors relatively recently. Therefore, they still have the short digestive tracts of a carnivore, which does not allow them to efficiently digest plant matter. That is why bear scats sometimes look like they went right through the bear without any digestion whatsoever.

The Importance of Soapberry

There are no major salmon runs into the Kennicott Valley proper. Because of this, soapberries represent an important nutritional resource for local bears because they are high in energy and are easily digestible. They are a rich, concentrated food resource that allows bears to put on adequate fat reserves for successful reproduction and hibernation. The large population of bears in the Kennicott Valley is partially a result of it being an important seasonal concentration site for bears feeding on soapberry, similar to the seasonal concentrations of bears seen at salmon streams throughout Alaska. Soapberry may also influence the occurrence of bearhuman conflicts.

Genetic data from my study show that new bears enter the Kennicott Valley as soapberry ripens. Many of these bears are likely naive with respect to humans and thus more prone to come into conflict with them as they wait for berries to ripen. In fact bearhuman conflicts in the Kennicott Valley peak sharply in July and decrease abruptly thereafter. The sharp decrease in bearhuman conflicts after the July ripening of soapberry suggests that once berries ripen, bears concentrate on them and are less likely to come into conflict with people. While feeding on berries, bears are very focused on the important business of eating and avoid interactions with humans.

Killing Bears May Actually Perpetuate BearHuman Conflict Occurrence

The Kennicott Valley is unusual in that it is surrounded by a large relatively unhunted bear population. Therefore, it provides an interesting case study of the impacts that humans can have on local bear populations. The major impact that humans have on bears is through mortality. As discussed in last issue’s article, at least 24 bears, and perhaps as many as 36, were killed by humans in and around the Kennicott Valley from 19992001. Although you might suspect that this would reduce the number of bears in the area and thus the occurrence of bearhuman conflicts, the actual effect may be the exact opposite.

Killing bears does not necessarily prevent the future occurrence of bearhuman conflicts and is not a learning experience, for either the bear or the humans involved. Killing bears in the Kennicott Valley has a twopronged impact on bearhuman conflicts: it creates a “power vacuum” in which there is no check on the influx of young inexperienced male bears into the valley, and it removes “humansavvy” bears from the population which have learned how to live around humans and their developments. For example, killing resident “human savvy” adult female bears prevents them from passing on their hardearned survival skills to their offspring. Killing male bears may simply create opportunities for dispersing individuals to establish home ranges in the valley. The reasons for this are directly related to the dominance hierarchies that govern bear populations.

Bear populations are governed by their social structure, which is based on a dominance hierarchy where the largest and most dominant animals influence the composition and distribution of the rest of the population. In a normally functioning “bear society,” adult males are at the top of the dominance hierarchy, and newly independent subadult bears and cubs are at the bottom. Bears establish and maintain their social position by acting aggressively. For example, adult male bears regulate population densities by preventing dispersing subadult males from establishing home ranges near them. Adult male bears generally avoid areas of human activity and stake claim to the best available habitat. As a result, young bears often settle near humans, which may actually provide them some respite from persecution by older dominant males. For example, researchers have reported that 76% of the bears they captured in campgrounds, garbage dumps, and residential areas in Minnesota were young males. This facet of bear biology has direct implications for bearhuman conflicts in the Kennicott Valley.

If adult males are absent from an area, through humancaused mortality or avoidance of human activities, their absence may result in an influx of dispersing subadult males. Their numbers can then build up to unusually high densities because there are no “social” factors preventing them from doing so. Many of these young bears have little or no experience with humans. The combination of increased numbers of subdominant bears in an area and their propensity for foraging on human foods and garbage leads to increased bearhuman conflicts in those areas where adult males are absent.

Genetic data from my research supports this scenario, as there is an unusually dense population of bears in the Kennicott Valley, a dispropor¬tionate number of which are male. For example, bear densities within a 4kilometer radius of the end of the McCar¬thy Road are approximately 1 bear/km2, 72% of which are male (this is about 10 times the densities reported for other interior Alaskan bear popula¬tions). These facts alone suggest that these are mostly young bears (mature males generally do not tolerate this many male bears in such a small area). Not coincidentally, the area at the end of the McCarthy Road is also a dense “bullseye” of bearhuman conflict occurrence. This area is good berry habitat, is a natural travel corridor, and is an area of concentrated human attractants, and so is attractive to bears.

Not all bears killed in “defense of life and property” (DLP) circumstances are necessarily “problem” bears. I observed that following high profile bearhuman conflicts in the Kennicott Valley, there is a concurrent rise in the number of bears which are killed in “defense of life and property.” Some of these bears are likely innocent of any wrongdoing, other than being in the wrong place at the wrong time. I was able to determine ages for 8 humankilled bears (5 subadult males, 1 adult female, 2 adult males) by analyzing crosssections of their premolar teeth. Because most bears killed by humans are subadult males, (which never reach adulthood and thus are never able to assert their dominance and prevent the influx of more juvenile bears into the valley) normal social hierarchies are disrupted and the “power vacuum” of attractive habitat remains open to future generations of dispersing subadult bears. The process continues full circle. Rather than killing bears, we would be better off trying to maintain an “educated” resident bear population.

The Kennicott Valley as a Grizzly Bear Population Sink

The highrates of human caused bear mortality in the Kennicott Valley, the quality of its natural food resources, and the widespread availability of human attractants may cause it to function as a population sink for surrounding bear populations, particularly for grizzly bears. A population sink is an area in which the number of deaths exceeds the number of individuals that are born or immigrate into that area.

Based on genetic data from my study, we can say with some confidence that the Kennicott Valley functions as a population sink for grizzly bears. Eight individual grizzly bears were genetically identified in my study, 4 of which were killed by humans, including 1 adult female and 2 cubs. This is in addition to the adult female with 2 cubs which were killed in 1999. Of the 4 grizzly bears presumed to have survived, only one was a female. Because grizzly bears only reproduce approximately every 4 years and only have 13 cubs per litter, we can see that local mortality rates easily exceed the local recruitment potential. This trend represents a microcosm of what has happened to grizzly bears in the lower 48 and does not bode well for grizzly bears in and around the Kennicott Valley.

Aversive Conditioning

A better alternative to killing bears is to first try to aversively condition, or educate them. Aversive conditioning will only work, however, in conjunction with everyone keeping a “clean camp.” One disturbing trend I noticed in the course of my research was the willingness of people to intentionally wound bears, including grizzly bears, with bird shot, buckshot, and .22's. This practice can cause longlasting festering wounds in bears and unnecessarily creates a potential community safety hazard. Who knows how these bears will react the next time they encounter a human in the woods? Under no circumstances should a bear be intentionally wounded. A better alternative is to use rubber slugs, rubber buckshot, or bean bag rounds to “educate” bears through their rearends. Mason Reid, WrangellSt. Elias National Park’s (WRST) wildlife biologist (9078227400), can provide more information on sources of aversive conditioning products (including air horns and aversive conditioning rounds) and how they should be used.

Bear “savvy” dogs can also provide a very effective bear deterrent for Alaskans living in the bush. For example, the Canadian Eskimo dog was the original defense of the Inuit against the polar bear. This breed has a 1,000year history of interdependence with Inuit hunters in the Canadian arctic, who used it as a draft animal and as a hunting dog. These dogs would aggressively attack and hold polar bears at bay for Inuit hunters with little fear for their own life. Frank Glaser called them the “best d___ bear dogs in the world” in Jim Rearden’s classic book, Alaska’s Wolf Man. Another good breed, the Karelian bear dog, is routinely used to aversively condition bears in the lower 48. However, specialized breeds are not necessary to get a bear’s attention when it is investiga¬ting a homesite. Bears seem to have an innate regard for dogs in general, whether they be mongrel or purebred.

The Importance of WrangellSt. Elias to Grizzly Bear Conservation

The basic reason that most of us have chosen to live in Alaska is because we cannot take a landscape overrun with humans and denuded of its wildness. There is really no true wilderness left in the lower 48. However, here in Alaska if you walk off most any road for a halfmile, you are in the howling wilds. One measure of this wildness is the presence of bears, particularly grizzly bears, which are particularly vulnerable to the impacts of modern civilization.

Surveys have shown that Alaskans want to keep bears around and that both residents and visitors value bears as a renewable resource and as animals that can be observed and enjoyed. In the lower 48, grizzly bears have been reduced to less than 2% of their former range and their numbers have been reduced from at least 50,000 animals to less than 1000 in less than 200 years. Considering this sad “conserva¬tion” track record it is safe to say that grizzly bear populations in Alaska will not survive without a conscious effort by all Alaskans to safeguard bears and bear habitat.

Alaskans are fortunate to have one of the last large grizzly bear populations left in the world, but it should not be assumed that we always will. Our state is home to more than 98% of the grizzly bears in the United States and more than 70% of the grizzly bears in North America. The longterm preservation of grizzly bears is likely to be contingent on the preservation of large chunks of wild country that are relatively free from human disturbance. In fact, the major threats to bears throughout the world are loss of habitat and humancaused mortality. Therefore, both we and the bears are fortunate to have large protected areas such as WRST to provide a refuge for these striking symbols of the American wilderness.

WRST is one of four conti¬guous conservation units (includ¬ing Kluane National Park, Glacier Bay National Park, and the TatshenshiniAlsek Provin¬cial Park) spanning some 24 million acres in Alaska and Canada that are recognized as an International World Heritage Site. Altogether it is the largest internationally protected area in the world. As a 13.2 million acre member of this complex, WrangellSt. Elias National Park & Preserve is a unique resource for the longterm preservation of grizzly bears in North America, and indeed, the world. The bottom line is simple. If we want to maintain stable bear populations in the long term, the number of bears that die, whether by human or natural causes, cannot exceed the number of births. This is particularly critical for grizzly bears, which have some of the slowest reproductive rates of any terrestrial mammal. The major challenge before us in the 21st century is to apply the lessons learned from the lower 48 in order to maintain our healthy and diverse bear populations into the future. In so doing we will also be preserving the wilderness which first lured us north to this Great Land in the first place.

Note of Interest

As part of my study, I surveyed bear foods and conducted a plant survey while doing my field work in the Kennicott Valley. I identified four plant species that were never discovered in the park before, one of which, Viola renifolia Gray v. brainerdii (a violet), Dee Frady discovered near her and Terry’s cabin on Fireweed Mountain. This discovery represented a significant extension of the known range of this species. The other species I collected were an arnica (Arnica chamissonis ssp. chamissonis), a paintbrush (Castilleja cf. miniata), and a mint (Scutellaria galericulata v. pubescens).

For More Information

Rangerled nature walks and talks are given throughout the summer in the Kennicott Valley. In some of these programs, rangers will discuss local bear ecology and point out common bear foods in the area. They will also talk about interpreting bear sign which hikers often encounter in the wilds of Alaska. For more information on nature walks and talks, contact Megan Brokaw, the Kennecott Interpretive Ranger at 9072597217. The park wildlife biologist, Mason Reid, can provide more information on bears in the park.

Acknowledgements

I would like to take this opportunity to thank Carl Mitchell and Devi Sharp, Wildlife Biologist (19972000) and Chief of Resources for WRST, respectively, for believing in and making this project possible. They were both critical to its success.

About the Author

Jim Wilder worked for WrangellSt. Elias National Park from 19982002 and studied the bears of the Kennicott Valley from 19992002. He currently works for the NPS Regional Office and participates in bear research throughout Alaska.