PATCHES of dark clouds drifted in the blue sky. The summer sun was bright and warm, giving the forest, cliffs, snow and glaciers a tinge of gold. We drove at a leisurely pace along Interstate 5 to Highway 20, which goes through the towns of Hamilton and Winthrop, in Washington State, passing others such as Concrete and Marblemount. It was the 7th of July. The aim of our drive was to understand the ecosystem of the North Cascades, where plans are afoot to reintroduce grizzly bears ( Ursus arctos horribilis ). Our journey back to Seattle was along Highway 53, through Darrington and still within the North Cascades; the distance we covered that day was 260 km.
We were accompanied by the biologist Rob Wingard of the Washington Department of Fish and Wildlife, a former graduate student of Paul Krausman. His knowledge of the area and wildlife was immensely useful to help us understand the landscape and its wildlife. As we drove along, we saw numerous people driving, trekking and admiring the scenery from vantage points. Most of them possibly had no idea that the landscape had contained grizzlies in the past and that the bear might return in the not-too-distant future.
Biology of the speciesThe grizzly bear is a large subspecies of the brown bear, which inhabits North America and Eurasia. The scientific name of the subspecies that occurs in Eurasia is U. a. lasiotus ; the brown bear in the Himalayan region is U. a. isabellinus . Adult female grizzlies weigh in the range of 130 to 180 kg, while adult males weigh between 180 kg and 360 kg. The average total length of a grizzly is 198 cm, with an average shoulder height of 102 cm.
One study reported that the average weight of an inland male grizzly was around 272 kg, while that of a coastal male was around 408 kg. For a female, these average weights were 136 kg for inland animals and 227 kg for coastal animals. This is due in part to the variation in the richness of their diets. In Yellowstone National Park (mostly in Wyoming but extending to neighbouring Montana and Idaho) in the United States, the grizzly bear’s diet consists mostly of whitebark pine nuts, tubers, grasses, various rodents, army cutworm moths and scavenged carcasses. Sadly, a large number of extremely valuable whitebark pine trees are dying out as a result of white pine blister rust, an introduced pathogen. The whitebark pine is also vulnerable to infestation by mountain pine beetles and because of factors relating to climate change and altered fire regimes. None of the food sources mentioned above, however, match the fat content of the salmon available in Alaska and British Columbia, where the grizzlies grow heavier. It is not uncommon to encounter grizzlies in Alaska weighing 540 kg. These grizzlies supplement their diet of salmon and clams with sedge grass and berries.
A grizzly bear’s diet consists of about 90 per cent vegetable and insect matter. Among the vegetable matter, berries are the dominant food source, providing calories and ultimately the fat required by a grizzly to survive, hibernate and reproduce. The North Cascades landscape is rich in berries, and 100 of the 124 identified food plants of grizzly bears south of Alaska occur here.
Although variable in colour from blond to nearly black, grizzly bear fur is typically brown. A pronounced hump appears on its shoulders; the hump is a good way of distinguishing a grizzly bear from a black bear ( U.americanus) as black bears do not have this hump. Apart from this, a grizzly bear can be identified by the dished-in profile of its face with short, rounded ears, whereas the black bear has a straight face profile and longer ears. The grizzly bear can also be identified by its rump, which is lower than its shoulders, while the black bear’s rump is higher. The front claws of the grizzly measure about 5 to 10 cm in length, while those of a black bear’s measure about 2.5 to 5 cm in length.
Range: past and presentIn North America, grizzly bears previously ranged from Alaska to Mexico and as far east as the western shores of Hudson Bay. Prompted and supported by President Thomas Jefferson (1801-09), Captain Meriwether Lewis and Lieutenant William Clark explored the wilderness of the uncharted western U.S. from May 1804 to September 1806, travelling from St. Louis to the Pacific and back and covering a distance of 12,375 km by boat, on horseback and on foot. At that time, an estimated 50,000 grizzly bears roamed between the Pacific Ocean and the Great Plains, across vast stretches of open and unpopulated land. Lewis and Clark had several hair-raising encounters with grizzlies. At one point, the exploratory team had a very close encounter with a grizzly bear and had to fire eight bullets; only the last bullet hit the bear in the head and killed it. As the expedition team lived off the land, it killed, along with other animals, 43 grizzlies and 23 black bears for food.
The indigenous people saw the grizzly as a teacher, guide and symbol of strength and wisdom. However, when the pioneers moved into the interior of the U.S., bears were persecuted and their numbers and range declined drastically. As European settlement expanded over the next hundred years, towns and cities were established, and the habitat of these large omnivores, along with their numbers, shrank drastically. Today, in the western U.S., only a few small corners of grizzly country remain, supporting five populations of about 1,800 wild grizzly bears. Of the 37 grizzly populations present in 1922, 31 were extirpated by 1975.
As a result, the grizzly bear was listed as threatened under the Endangered Species Act on July 28, 1975. Following the listing, the U.S. Fish and Wildlife Service initiated a recovery effort at establishing viable populations in sections of four States where the grizzly bear was known or believed to exist. The existing grizzly bears, all in the western U.S., are managed within six recovery zones: the Greater Yellowstone Ecosystem in Wyoming and south-west Montana, the Northern Continental Divide Ecosystem in north-west Montana, the Cabinet-Yaak Ecosystem in extreme north-western Montana and the northern Idaho panhandle, the Selkirk Ecosystem in northern Idaho and north-eastern Washington, the Bitterroot Ecosystem in central Idaho and western Montana, and the North Cascades Ecosystem in north-western and north-central Washington.
North Cascades EcosystemThe awe-inspiring grizzly bear may be exceedingly rare in the rugged North Cascades Ecosystem, and it is difficult to obtain precise information on its status as 94 per cent of this approximately 25,000 sq. km area has few trails. The valleys and slopes on the western side of the landscape, which receives 200 to 250 cm of rainfall annually, are densely wooded with tree species such as alder, big-leaf maple, black cottonwood, Douglas fir, mountain ash, mountain hemlock, silver fir, subalpine fir, western hemlock, yellow cedar and western red cedar. The thick understory contains species such as blueberry, bracken fern, Himalayan blackberry, Oregon grape, red elderberry, salmonberry, thimbleberry and trailing blackberry. The Himalayan blackberry is an exotic species from Europe with powerful curved thorns, and its fruit output is the highest among berries. The conspicuous colourful plants in the lower part of the landscape west of the Cascade Crest are fireweed, foxglove and Douglas spirea. All were rosy red.
The forests on the eastern slopes and valleys receive comparatively less rain, which can vary from 25 cm in the far east to 200 cm in the west. The higher altitude slopes in the east are clothed in sub-alpine larch, whitebark pine and other tree species such as Douglas fir, lodgepole pine, ponderosa pine and western larch. The ponderosa pine is adapted to fire and drought. Bear food plants are snowberry, serviceberry and thimbleberry. Some of the colourful flowers seen east of the crest are the broadleaf arnica with golden flowers, the Cascade penstemon with blue flowers and the common paintbrush with reddish pink flowers. The greater North Cascades Ecosystem constitutes a large block of continuous habitat that spans the international border between the U.S. and Canada, but it is isolated from grizzly bear populations in other parts of the two countries. It is a landscape of granite peaks, alpine meadows, forests of conifers and broad-leaved vegetation and sagebrush-filled valleys. The U. S. portion of the ecosystem spans the crest of the Cascade Range, from the temperate rainforests of the western side to the dry ponderosa pine forests and sagebrush steppe on the eastern side, and comprises one of the most intact wildlands in the contiguous U.S. Historical records indicate that grizzly bears once occurred throughout the North Cascades Ecosystem. It is reported that with the boom in the fur trade in the 19th century, nearly 3,800 grizzly bear hides were shipped out of the area forts in one 25-year period.
Support for restorationStudies by eminent bear biologists such as Chris Serveen, Jon Almack and Andrea Lyons have concluded that the North Cascades Ecosystem contains sufficient habitat quality to maintain a minimum population of about 200 grizzlies. A 2016 poll conducted throughout Washington State showed strong support (80 per cent) for grizzly bear restoration in the North Cascades. In this regard, the U.S. Fish and Wildlife Service and the National Park Service have prepared a 325-page Draft Grizzly Bear Restoration Plan/Environmental Impact Assessment in January 2017, which will be finalised with inputs from stakeholders in the winter of 2018. At present, the State of Washington cannot be involved with this programme because its wildlife laws do not permit translocation of predators to lands under its control. So bear restoration will be initiated only on federal forest lands.
The grizzly bears for reintroduction will be translocated from areas rich in berries such as north-western Montana, which has Glacier National Park, and a 1,000-strong bear population that is growing. Grizzly bears in the North Cascades would scavenge cougar (mountain lion, or puma) kills (deer and elk) and dig out ground-dwelling rodents (the colony-living hoary marmot, each approximately weighing 5 kg; the large-colony-living Columbian ground squirrels, about 500 g) from their burrows. Ungulates on which the grizzlies can prey or scavenge from cougar kills are mule deer, black-tailed deer, white-tailed deer (the estimated population in the Cascades is 50,000), elk (7,500), big horn sheep (1,000), mountain goats (1,200) and moose (the largest deer species), which is establishing a population in the north-eastern part of the Cascades. As we drove on July 7, we saw five mountain goats and two white-tailed deer.
Wolves, which can kill grizzly cubs, are exceedingly rare in the Cascades. Yet, according to the wildlife biologist Jeff Stetz, the abundant black bear, although it is no match in a direct confrontation with the grizzly, would compete with it for berries through exploitation competition and thereby reduce the reproduction and recruitment of the grizzly. This aspect needs to be monitored and corrective measures need to be taken if required. The programme should expect some amount of conflict in valley habitats in fringe areas where people live, farm and maintain livestock, including horses. Better livestock management and appropriate and speedy compensation should be the means to address this problem. For guidance, wildlife managers can look to Idaho, Montana and Wyoming where large predators have been re-established.
Rivers and salmonThe alluring aspect of the North Cascades landscape for grizzly bears, besides its temperate rainforests, is its beautiful rivers. We crossed the Baker, Skagit and Methow rivers and drove along the banks of the Skagit and Sauke rivers. The rivers with their turquoise-blue water fringed by dense forests were a sight to behold. Before the Baker and Skagit rivers were dammed, all five species of Pacific salmon (chinook or king, coho or silver, pink or humpback, chum or dog, and sockeye or red), non-migratory rainbow trout and steelhead thronged the rivers, which the native people harvested for food.
Now there is no facility for the fish to travel upstream the Skagit, beyond Gorge High Dam (91 m). Several ingenious steps have been taken to help the salmon and steelhead spawn in the lakes of the Baker river. This includes collection of fish from the river near the Lower Baker lake and transporting them to the Upper Baker lake using trucks, creation of spawning beaches in the Upper Baker lake, setting up a salmon and trout rearing facility and capture of juveniles in the Upper Baker lake and transporting them to the river below the Lower Baker lake. As a result, even today, all the five species of Pacific salmon and the steelhead spawn in the rivers in the landscape, and perhaps one day the introduced grizzlies will be able to capture and feed on these nutrient-rich fish. Because of all these endeavours, for modern visitors, the flowing waters of the North Cascades are a source of recreation, education, inspiration and hydropower.
Reintroduction plansThe North Cascades is an isolated grizzly habitat as the Fraser river and the Trans-Canada Highway form a barrier between the Cascades and the grizzly habitat in British Columbia (Canada) and two national railroads break the connectivity with the grizzly habitat in Montana and Idaho. High levels of human activity in this broken corridor will preclude the bears from nearby areas colonising the Cascades, and so translocation from other areas becomes the only option to build up the population. The three options the restoration team is planning are to release up to 10 bears within the first two years of the project and monitor them; release up to 25 bears over five to 10 years; or release sufficient number of bears that would result in a population of 200, including bears added through reproduction, over a period of 25 years. The sex ratio of the released animals would be 60-80 per cent female and 20-40 per cent male.
Grizzlies would be transported by helicopter and released in remote areas on National Park Service or U.S. Fish and Wildlife Service lands or U.S. Forest Service lands. Animals would be released close to one another, which would facilitate interaction and ultimately result in breeding. All translocated grizzlies would be fitted with Global Positioning System collars before release to monitor habitat use and spatial distribution. Tissue samples would be collected before release for genetic-monitoring purposes.
Suggestions and hope for the futureLouisa Willcox, project director of the Wild Bears Project of the National Resource Defence Council, writing on March 13, opines that grizzlies remind us that we are all related: they stand on hind legs, eat the same food as we do and nurture and ferociously defend their young. Restoring grizzlies in some of Washington’s wildest country is a way of undoing at least some of the harm perpetrated by America’s European ancestors. Louisa Willcox provides two valuable suggestions: managing and even closing roads on public lands, as back country roads are often used by poachers, and effective law enforcement to control poaching. These are extremely valuable suggestions as poachers in the back country shoot not only deer, the food of grizzlies, but the bear itself.
The U.S. Fish and Wildlife Service and the National Park Service record that the return of a self-sustaining population of grizzly bears to the North Cascades would bode well for the ecosystem. An ecosystem capable of supporting grizzly bears, complete with healthy vegetation and prey populations and secure remote habitats, would also be capable of supporting the other species that call this ecosystem home.
A.J.T. Johnsingh is with the Nature Conservation Foundation, Mysore; WWF-India; and the Corbett Foundation. Paul R. Krausman is a professor emeritus at the University of Arizona.
Theauthors would like to thank thefollowingpeoplefor their help in writing this article: Madhavi Sethupathi, John Seidensticker, Cliff Rice, Jeff Stetz, Rob Wingard, Gary Gazel and Fred Koontz .
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