|Paradise in Peril: Chilkoot's Brown Bears|
by Lincoln Larson
March 10, 2004
: The Chilkoot Brown Bear Project
I uttered the habitual salutation as I began the trek down from my isolated research cabin to the banks of Southeast Alaskaís Chilkoot River. Although I saw no evidence of recent bear activity through the light of my headlamp, I had no intention of startling a 700-pound sow with cubs in the predawn of that cold, rainy September day. At 5:00 AM, I was the only human being walking along the river.
As I approached my observation post, I heard splashing nearby. Straining my eyes in the darkness, I struggled to find the source of the commotion. Through my binoculars, I could just a make out the silhouette of a subadult grizzly devouring salmon carcasses on the riverís far bank, 60 meters away. At that distance, I was in no danger. Suddenly I froze. A large, dark form shot into my field of view, no more than 10 meters away. Even in the dark, I immediately recognized the shape of a large female brown bear. As I slowly and quietly backed away, two cubs ran up the bank and onto the road where I was standing. I managed to move behind the trunk of a spruce tree. My trembling fingers clutched the cannister of bear spray fastened to my beltóa last resort in case of a grizzly charge. The bears were obviously aware of my presence, but upwind, and in the dark, they were unable to locate my exact position. After over a minute of intense sniffing and scanning, the large sow eventually decided to saunter off downriver. The cubs bounded off behind her, and I breathed a heavy sigh of relief. I had emerged unscathed and transformed after my closest grizzly encounter while working on the Chilkoot Brown Bear Project.
Chilkoot Study Area
Inquisitive Subadult Bear
: Studying the Chilkoot Bears
The Chilkoot River flows about one mile out of Chilkoot Lake and into Lutak Sound, 10 miles north of Haines, Alaska. Every year, four different species of salmon (pink, sockeye, chum and coho) return to the river to spawn. The largest run occurs in September, when over 100,000 pinks and sockeyes (see note below) enter the icy waters to breed. The abundance of salmon attracts many predators to the Chilkoot each fall, including bald eagles and grizzly bears. Hundreds of fishermen and tourists also follow the salmon upstream to capitalize on the extraordinary angling and wildlife-viewing opportunities. This unique situation, a wild Alaskan River with easy road access, raises multiple conservation issues centered on the preservation of Chilkootís grizzly bears.
Taking advantage of the ideal setting, the Brown Bear Project focuses on bear foraging ecology and habitat use patterns in relation to the riverís human activity. For two months beginning in mid-August, the research team observed and recorded bear and human behavior along the river corridor. We were stationed at designated points along the river for three-hour shifts at sunrise and sunset (mixed with the occasional midday observation). Though spectators avoided the river on cold, rainy days, adverse weather conditions did not deter the bears or the researchers. We logged many hours huddled in freezing rain, inspired by the rapture of field biology and our majestic surroundings. The observation posts were concealed and did not obstruct bear access routes to the river. As a result, both tourists and bruins were rarely aware of our presence. Using video cameras, binoculars, and tape recorders, we documented human and bear activity throughout the three-hour periods.
From August to October, we viewed 16 different bears (not counting cubs) foraging along the Chilkoot River. Each of these bears was either an adult female (some with litters of up to four cubs) or a subadult (age 2-3 years). The large males presumably stayed deeper in the mountains, farther from the threats posed by hunters and civilization.
During the project, I became very familiar with all the individual bears and their idiosyncrasies. The grizzlies displayed a variety of different fishing techniques. While many of the subadults ran, jumped, and futilely flailed at fish in the swiftly moving water, the older bears had clearly refined their skills. One mother preferred snorkeling for salmon, another opted to wait patiently before plunging on unfortunate passersby, and another had mastered a herding technique, chasing fish into pools with no outlets. The cubs enthusiastically attempted to imitate their mothersí tactics, but experienced little success. They often left the water and frolicked on the riverbanks, anxiously awaiting the delivery of their next meal.
As the season progressed, the bears began to consume fish carcasses at a higher rate. Live fish offer a richer energy content but, with hibernation looming, bears desperate to pack on the pounds seemed to prefer quantity instead of quality. Individual bears developed certain routines that made their spatial and temporal habitat use patterns very predictable. One adult female emerged from the same spot in the forest at exactly the same time (virtually down to the minute) for five consecutive days, constantly fishing the same segment of the river. With many bears in a relatively small area (up to seven bears were sometimes visible along a 100 meter stretch of river), confrontations and chases between grizzlies unwilling to share fishing spots often occurred. Sows with cubs dominated the riverís feeding hierarchy, and smaller subadults were frequently forced to retreat. All the bears faced one common obstacle, however: human disturbances.
NOTE: Fish counts are conducted at the Weir, a man-made structure composed of a series of closely-spaced bars designed to block fish movement upstream while permitting the free flow of water. A few bars are lifted several times a day, creating a small opening through which fish can pass. Fish & Game Officials count the salmon as they swim by. After spawning, the salmon die and their bodies float downstream. Bears often congregate at the Weir early in the morning to pick the fish carcasses off the bars.
Fishing Along the Chilkoot
Subadult Feeding on Carcasses
: The Impacts of Human Activity
Evidence indicates that human activity greatly influences brown bear activity. Bears were most active in the extreme early morning and late evening, corresponding to the minimum in angler and vehicle densities. Bears in more remote locations, such as Alaskaís Katmai National Park, prefer to fish during the daylight hours when live fish capture rates are much higher. The Chilkoot grizzlies, however, choose to forage in the dark to eliminate human disturbances. With humans in the vicinity, the bears experienced decreased fishing success and often resorted to eating fish carcasses while maintaining constant vigilance. In some instances, vehicle traffic along the road was so heavy that bears were denied access to the river.
Sows with cubs generally showed less tolerance for humans, possibly due to the recent shootings of several young bears that some members of the local community perceived as threats. In most cases, these cubs discovered garbage that had not been properly disposed, and they began to associate humans with food. Food-conditioned bears are reluctant to exploit the valuable salmon resource of the river, electing to scavenge trash cans and fishermenís coolers in search of an easier meal. As people from around the world flock to the Chilkoot River each fall to witness the amazing bear-feeding spectacle, the number and intensity of bear-human interactions will continue to grow. Men and bears are capable of coexistence, but the volatile situation along the Chilkoot demonstrates that proper management techniques are necessary to ensure a relationship beneficial to both species. We must give the animals some space in order to encourage and appreciate their natural behavior.
As my experience with the Chilkoot brown bears confirms, the common perception of grizzlies as menacing monsters and man-killers is completely unwarranted. While the bears certainly offer an imposing, commanding presence, they are generally benign, intelligent creatures that should be revered, not feared. The Chilkoot River System provides an excellent case study for wildlife management techniques around Alaskaís salmon streams. If we can understand the effects of human habitat use and recreation in this river ecosystem, we can begin to develop strategies for protecting bears in other areas.
Special thanks to Lori and Anthony Crupi, founder and
director of the Chilkoot Brown Bear Project.
About the author:
Lincoln Larson is a recent graduate of Duke University (Durham,
North Carolina) and an aspiring field biologist.