Grizzlies and Ungulates
Large ungulates, when present, enrich the grizzly environment by contributing additional variety to the diet. Caribou dying from old age or disease are a sporadic source of carrion, as are the partially devoured caribou kills made by wolves. Although grizzlies are not slow, they are not fast enough to capture a healthy caribou that is beyond the age of early calfhood. However, a nominal number of very young calves do fall prey to bears (Fig. 43).
Each spring McKinley National Park caribou herds, numbering about 8,000 in 1962, after spending the winter along the north boundary of the park and northward toward Lake Minchumina, migrate through the park to Windy Creek country on the south side of the Alaska Range. After feeding for a few weeks in the Windy Creek area, they recross the Alaska Range, most of them traveling westward to the Thorofare River and beyond (Fig. 44).
Calving takes place between 15 May and 15 June, chiefly during the period that the caribou are moving toward the south side of the range. The time of migration and the route may vary from one year to another, so that the height of the calving season may occur in different localities in different years. In 1939, for instance, most of the calves were born near Wonder Lake. By the time the herds had reached Polychrome Pass and Teklanika River, most calves were old enough to be no longer vulnerable to a grizzly attack. The next 2 years, calving took place far to the east, much of it between the Teklanika and Savage rivers, giving the bears in that area an opportunity to capture young calves. In 1965 many young calves were present between Sable Pass and Toklat River. Hence, the bear inhabitants in this section of the park were thoroughly calf-conscious for a period in late May and early June.
I should add that I noted no special movement of bears into a calving area for the purpose of preying on calves. If the calving took place in one area consistently and was concentrated more than it is, one could conjecture that some bears develop a movement pattern that takes them to a calving ground for the annual calving period. Bears ranging during any calving season where caribou are scarce or absent probably are not aware of missing anything, and subsist on other springtime fare.
Grizzlies in calving country are aware of the potential vulnerability of calves, and may be seen chasing bands of caribou on the chance that a calf too young to escape will falter and fall behind. Caribou bands generally are chased indiscriminately, perhaps often without the bear knowing whether a calf is present. Bears hunt on a percentage basis. If the season is right, fortune strikes sooner or later and a young calf is overtaken.
Newborn calves gain rapidly in strength and within a few days of birth are strong and fleet enough to escape the grizzly. As the calving season wanes, hunting success drops. The meat-hungry bears may continue to chase caribou for a time after the season for weak calves has passed, but a series of failures soon discourages them. Once they recognize that chasing caribou is no longer profitable, they resign themselves to the inevitable, forget about calves, and for the rest of the summer pay little heed to caribou.
Below I describe some of the behavior and hunting incidents involving grizzlies and caribou, chiefly during the calving period.
Alert to Calf Possibilities
On 6 June 1961 a mother and her blond yearling cub moved down a slope of Igloo Mountain. She must have been hungry for meat because she was especially interested in caribou encountered as she moved down the slope. When she saw three caribou bulls feeding in tall willow brush some distance below her, she stopped and watched for 4 minutes. After moving down a little farther, she again stopped to watch the bulls, now only about 60 yards away. The bulls discovered the bears and trotted away. A little later she caught the scent of caribou, stopped, raised her muzzle to test the air, then proceeded at a fast walk. The yearling cub, seemingly aware that his mother was bent on a hunting project, remained behind resting on his stomach with nose between paws, watching the mother advance. After traveling forward a hundred yards, the mother stopped, raised her muzzle to scent the breeze, then stood erect on hind legs to look around. Soon a large bull caribou 25 yards away became aware of her and trotted away briskly. The bull did not interest her. The cub seemed to decide that the incident was finished and galloped down the slope to join his mother. Both moved forward, the cub in the lead. The mother then reached forward and pushed the cub aside with a paw and loped into a hollow grown over in tall willow brush where she and the cub became hidden from my view. Another bull caribou emerged from the hollow, stood looking into the hollow, and seemed uncertain of the position of the bears. In a minute he noted the proximity and galloped away. The bears were able to make a close approach because the breeze favored them. Lower on the slope, two more bulls were similarly flushed out of a draw. The mother bear seemed especially hopeful that an opportunity for capturing a calf would develop but there were no cows or calves on the slope. She then turned to feeding on roots and grass.
The behavior of caribou varies on different occasions. One day caribou may be complacent when near bears, and on another occasion they may be especially timid. On 3 June 1955 I discovered a band of 30 caribou hurrying away from a bear standing 300 yards to their rear. Possibly the bear had been chasing them and they were continuing their flight, taking no chances. A band of 100 caribou was hurrying away from another bear who was walking toward them far to their rear. Perhaps they too had been chased. Later on the same day I saw a small band galloping away from a bear, but the bear was making no threat to pursue. All these groups consisted chiefly of cows and calves so they had cause to be prudent.
On 20 May 1961 three migrating caribou cows showed more than usual concern on seeing a mother bear and yearling. The cows stopped 300 yards from the bears, watched briefly, then changed their course so as to pass far to one side of the bears. None of the cows had a calf so their extreme wariness seemed unnecessary. Their concern may have been associated with the seasoncalving time for one or more of the cows may have been imminent, causing behavior appropriate to the presence of a vulnerable calf in bear country.
Only Slight Reaction to Grizzlies
On 26 May 1961 a blond bear on an old river bar took a course parallel to and about 150 yards from a herd of 250 caribou, among which were many calves. The caribou seemed to take little note of the bear; only two or three cows seemed at all concerned. The long line of caribou drifted slowly, almost imperceptibly, a little to one side of the bear's line of travel. I expected the bear to make a try for a calf but instead he moved a short distance beyond the herd and, during the hour that I watched, dug roots.
The following day, on the same river bar, I saw what appeared to be the same bear approaching another large herd of caribou. A short distance from the herd he stopped and fed for 25 minutes in one spot, probably on the remains of a calf. He then walked parallel to the herd and not far from it. Several caribou that were lying down stood up to watch the bear, but most of the herd paid little attention to him and continued grazing. I noted several calves near the far end of the herd and thought the bear might make a try for one, but instead he chased and captured a ground squirrel, then fed briefly on roots before moving slowly up and over a low hill. The bear was apparently not very hungry for meat. Of course, he did capture a ground squirrel, but no bear can resist chasing a fleeing squirrel. Feeding on roots on these two occasions suggests that bears prefer a mixed diet.
On the morning of 6 July 1948 over 200 caribou were resting in a sedge meadow near the Toklat River. Beyond the caribou, near the base of a slope, I discovered a mated pair of bears also resting. During the course of the next few hours, the bears crossed the meadow three times at the spot where the caribou rested and fed. On each occasion the caribou merely moved aside enough to form a lane for the passage of the bears. A few times the female veered slightly toward the caribou, just enough to cause a slight widening of the corridor. The caribou seemed especially serene, perhaps due in part to the fact that the calf-hunting season had been over for several weeks. Furthermore, the bears were concentrating on mating (the herd of caribou probably had been accustomed to the maneuvering of the male and female).
On 4 July 1963, in the same area, a herd of about 300 caribou moved slowly to a snowfield up the slope when a bear passed. The caribou needed little stimulus to make this movement because the flies were beginning to bother them; they were already on the verge of retreating to the snow.
It often appears that caribou in a herd are less wary than when alone or in a small group. In a large herd responsibilities do not rest to so great an extent on each individual. (In a string of pack horses it is the horse in the lead that is alert and watchful. Put him farther back in the string and he becomes a follower.)
Futile Chases During Calving Season
During the calving season, there are many futile chases either because there are no calves in the fleeing herd or because the calves are old enough to escape easily.
On 12 June 1948 an optimistic bear spent 50 minutes chasing a group of caribou without results (Murie 1951).
On 1 June 1955 I saw a band of 30 cows and calves trotting easily along Polychrome Flats. Far in the rear, so far behind that it appeared to be a separate incident, was a mother bear galloping after the departing caribou. Over to one side were six caribou standing gazing at the passing bear. The grizzly finally quit the hopeless chase and backtracked toward two yearling cubs left three-quarters of a mile behind her on a gravel bar where, I assume, the chase had started.
On 28 June 1956 a grizzly galloped his fastest in the wake of about 20 caribou that quickly left him far behind.
On 23 July 1963 a bear was seen traveling quite near about 250 caribou. When the bear ambled a little toward the herd, there was a slow movement away by those animals nearest the bear. He could not resist chasing the herd which hurried up the nearby slope. Then the herd parted and came down the slope on either side of the bear. The bear reversed his direction but soon realized the chase was hopeless.
In the evening of 4 July 1949 four of us climbed a steep slope along the Toklat River to classify a large band of ewes and lambs. On an open grassy slope directly below, we saw about 200 caribou. A few near the edge of the woods attracted our attention by their running, and behind them we saw a mother grizzly and a 2-year-old cub emerge from the woods. The mother led the way, walking stolidly into the open. The caribou fled to either side as she progressed. When they came to the middle of the meadow, the cub could restrain himself no longer and galloped pell-mell down the slope after the caribou. In a twinkle they had disappeared into the wood and the cub was alone and out of sight of everything, including his mother. He stood on hind legs and walked seven or eight steps trying to see her; she sat erect on her haunches looking for the cub, but apparently less concerned than he. He probably was a little disconcerted to find himself alone. He started back the way he had come, was soon in view of his mother, and travel with her across the grassy slope was resumed.
A Very Young Caribou Calf Captured
On the morning of 24 May 1961 I watched three cows and a calf caribou trotting westward on Polychrome Flats. They were headed in the opposite direction from the eastward, spring migration. Looking for a possible explanation, far to their rear I saw a lone bear following at a steady gait and putting his nose to the ground repeatedly as though following a trail. I am not sure that he had seen the four caribou.
A little later a herd of 13 cows and 4 calves passed a little to one side of him, and he loped after them. Soon five of the cows without calves swerved sharply and the bear cut across after them, apparently unaware that no calves were present. In his experience a calf could be present in any group and he followed his customary routine of chasing the nearest group without trying to determine if a calf were present. The five cows made another sharp turn and stood watching the bear approach. He disregarded them and continued forward toward a cow and calf not discovered previously, standing a few hundred yards away. On seeing the oncoming bear, the cow, followed by the calf, trotted away slowly. Evidently the calf was very young, for after traveling a short distance it lay down and the bear soon reached it. The mother ran in an arc and joined the five cows that had been watching the bear pass by, and the group moved eastward again. I expect the mother later returned to the scene. The bear fed on the calf for 40 minutes, then walked 100 yards away and disappeared in the rain and fog that had moved in.
Within 2 miles of this bear there were two other bears playing (probably 3- or 4-year-olds) as they traveled toward a slope; two more young bears about the same age were digging roots; one lone bear was traveling and another feeding on a carcass. However, only the one incident was observed during the morning, although many caribou were moving through the area where these seven bears were active.
Often one finds a worried mother caribou attending a bear that is feeding on her calf. She may remain nearby for a day or longer. On 2 June 1962 a mated pair of bears was feeding on a calf on tundra, near the East Fork River. Two caribou cows were circling and watching the bears helplessly. The second cow probably was a "sympathetic" companion who had joined the distressed mother. I have seen this behavior in other instances among caribou and once I saw a cow moose join another cow moose whose calf was in distress.
Food Preferred to "Love"
On the morning of 31 May 1963 I saw a large, dark male following at least half a mile behind a female, so far behind that she was out of sight, forcing him to follow her trail. He was patient and moved along slowly. She was on the prowl, no doubt hungry. After traveling eastward some distance, she turned south toward a band of about 90 caribou scattered and feeding on foothills one-half mile away. When she neared the caribou, she broke into a gallop. The caribou fled, hurrying off in a compact group. Quite soon the female bear stopped and apparently captured a calf that was too young to escape. She fed on the calf until the male, still moving deliberately, was about 200 yards away. She watched him approach then picked up the carcass and galloped up the slope with it dangling from her jaws, and disappeared behind hills. In time the plodding male, following her trail, also went out of view. The female obviously was not ready for mating.
Family Discovers Calf
On 8 June 1964 I saw a mother and yearling that I had watched frequently the year before, moving in an irregular course. She made a half-hearted, short dash at a lone caribou and then continued her irregular course, the yearling sometimes trailing 100 yards behind. I watched them for 1-1/2 hours hoping to get pictures of the cub showing its size. They settled down to digging roots on a slope for 15 minutes, then moved out of view over the top. A few moments later a caribou cow emerged from the spot where the bears had disappeared. It was using a fast, swinging trot, and obviously was startled by the bears. I climbed to where I could see the other side of the slope and saw the two bears feeding on a calf. There had been no chase, for the bears were feeding near the point where they had disappeared. The calf either was too young to escape or had been stillborn. The cub fed for half an hour and then rested against the side of the mother who kept pulling off little pieces and chewing them thoroughly. She fed for an hour before walking over to a snowpatch for a few bites of snow. The bears lay down out of sight of the calf remains. An hour and a half later, when the mother caribou moved up close to the carcass, the mother bear took a few steps to where it could see the mother caribou, looked briefly, yawned three times, walked back over the rise, and lay down again.
Three days later, while hiking up on Primrose Ridge, three of us came upon a caribou cow that also ran off with long, swinging strides, so effortless she seemed to be floating. When we passed that way later she paced away from the area as before. We searched and found her dead, newborn calf, perhaps stillborn. Our experience was similar to the bears'. If our sense of smell had been keener we would have found the calf when we first saw the cow.
A Bit of Inference
On the morning of 9 June 1964 I watched a bear in the distance walking steadily eastward until he came downwind from a group of seven resting caribou. Catching their scent, he made a right angle turn and lengthened and quickened his stride. He continued walking toward the caribou for 200 yards, and when he was about 75 yards away, they stood up and swung away to the west. The bear galloped toward the beds they had left, perhaps hoping that a calf had been left behind. He gave the spot a rather perfunctory sniffing and resumed his original eastward course. The caribou stopped, turned, and trotted after the bear, and when to one side of him stopped to watch him.
Old Male Attracted by Tumultuous Stream Crossing
One afternoon in early July 1947, several hundred caribou were resting on the gravel bars of Thorofare River. I approached and took movies as they splashed across the main channel of the river. Many of the calves lost their footing in the swift, glacial stream and had to swim. There was prolonged turmoil as scores of caribou crossed the stream and climbed a steep bank to the extensive green benches beyond. Then I noticed a big, male grizzly that was grazing on the opposite side of the river and had become aware of the commotion and excitement. Apparently, he concluded that this was an opportunity for food. He may have thought that the caribou were being attacked and one might be killed rather than expecting to catch a calf himself, for the calf-hunting season had been over for several weeks. He galloped ponderously down the slope off the green bench on which he had been feeding and continued across the gravel bar. I retreated, but he seemed unaware of my presence. By the time he reached the stream the last of the caribou were crossing. He plunged into the rapid current and pawed his way up the steep bank that had been made wet and slippery by the dripping herd. The caribou were all out of reach as their swinging gait carried them gracefully over the rolling tundra. The bear surveyed the situation, then grazed in a lush green hollow.
In May and June 1965, the drifted snow and late spring delayed the eastward migration of caribou so that between Sable Pass and the Toklat River caribou were present in larger numbers than usual during the height of the calving season. The grizzlies in the area were well aware of the calves so for a period the opportunity to witness grizzlycaribou behavior, as well as some wolf activity, was plentiful, and resulted in the following observations.
The Caribou Calf Season in 1965
I spent the first day of June 1965 in the Polychrome Pass area. A bear was first seen at the head of one of the branches of East Fork River. For about 10 minutes he fed in one spot, apparently on part of a carcass, then wandered southward. Twice he stopped to roll. There were no caribou ahead of him, so I moved on (Fig. 45).
Farther along I saw a lone bear traveling down to the Polychrome Flats, where small groups of caribou were feeding or traveling, and pass to one side of five caribou. They were unaware of each other because of the direction of the wind. He continued forward and when he was within 200 yards of a herd of 14 cows and 1 calf, he loped easily toward them. The caribou galloped away and dropped off the bench to a gravel bar, where eight of the cows swung off to one side and stopped to watch the bear as he galloped after the other six cows with one calf. The calf must have been quite young because it soon fell behind the fleeing cows. When the bear saw the calf fall behind, he put on extra speed and soon captured it. It had circled sharply and given the bear an additional advantage. He carried the calf 50 yards across the gravel bar, onto the dwarf birch-covered bench and started feasting. I moved on to look for two wolves, and when I returned an hour later, the bear was lying near the remains of the calf waiting for digestion to make room for more. He raised his head at intervals to look aroundhis only concern was another bear.
The mother of the captured calf returned and was maneuvering anxiously 100 or 200 yards from the bear when a second cow joined her and they moved about together. One-half mile away a lone cow with a calf approached and passed about 100 yards from the bear, unaware of her precarious location. The bear was sleeping off its big meal, and neither it nor a wolf resting nearby was much interested in calf scents.
About noon I discovered a lone bear to the west, chasing a group of five cows and three calves. It was a long chase but the calves were still holding their own fairly well after about half a mile. The chase passed several hundred yards south of the resting bear, then turned and came down the gravel bar toward the spot where the resting bear had made a capture earlier in the day. It had been a long run for the calves, and they were scarcely holding their own, about 100 yards ahead of the pursuing bear. The resting bear either heard or scented the chase to the east, for he stood up, galloped to the edge of the brushy flat, dropped down 10 or 15 feet to the gravel bar, and angled out to intercept the pursuing bear. Both were partly hidden by the bank when they met, but apparently there was a slight altercation. The one pursuing the caribou was the aggressor and the "local" bear galloped farther out on the river bar to escape. Before being overtaken, however, he stopped, and the two stood "glowering" about 15 feet apart. After a brief about face, the pursuing bear retreated to the west at a gallop and found the remains of the dead calf belonging to the other bear. It grasped the carcass in its jaws, started galloping, dropped the meat, and continued galloping toward the spot a mile away where I first saw it chasing caribou.
Far ahead I saw another bear watching the oncoming one. Its size could not be determined immediately, but as the galloping bear drew nearer it obviously was the well-known, dark mother hurrying back to her 2-year-old cub who had been left behind when its mother had chased caribou. As the mother neared him, the cub seemed uncertain of her identity and galloped a short distance away before coming forward to meet her. The mother, although hungry, was so concerned over her cub that she had dropped the carcass of the calf and hurried back to it. The altercation with the other bear on the river bar may have heightened her solicitude.
After joining her cub, the mother walked back toward the calf carcass, and the cub followed closely. When they reached the carrion, the two bears fed for 2 hours and then a nursing took place, after which the mother resumed feeding on the carcass and the cub rested on its side.
I stopped watching at 2:50 p.m. When I returned at 4 p.m., a herd of about 500 caribou was feeding on an old river bar far up toward the head of the west branch of the East Fork River. About a quarter of a mile beyond the caribou, the mother bear and her 2-year-old cub were traveling parallel to this spread-out herd, the cub romping ahead of his mother. They had traveled over 2 miles from where I had left them a little over an hour earlier. Occasionally, they stopped to dig a few roots. In the next 2 hours they moved around the herd in a long arc. A group of 20 caribou, including one calf, that the bears encountered moved off to one side. The cow with the calf was most circumspect for she moved out in front of the others. The bears went part way up a slope and lay down. After 10 minutes, the mother walked 20 yards, rolled over on her back, and the cub nursed. It was 6 p.m., and at 7 p.m. when I left the bears were still resting.
While these observations were under way, other dramatic activities were in progress. At 4:30 p.m. another lone bear, with nose close to the ground, moved about in circles over a sedge meadow. He moved into some gently undulating ground where I caught occasional glimpses of him as he continued working to unravel a trail. A lone caribou was flushed out and the bear galloped toward her but stopped where she was first seen, circled as before, but soon moved out of view. Fifteen minutes later he was working the sedge meadow again, but was soon back where the cow had been flushed out, and this time encountered a cow with a very young calf. A chase of 300 yards ensued, and the calf was captured easily. The bear had trailed persistently for 1 hour and 15 minutes, covering an area less than one-half mile in diameter. This persistent trailing to find a calf was seen rarely.
In the stretch of country between East Fork River and Toklat River, about 900 caribou, one bear family, and four lone bears were seen during the day.
On 2 June 1965 at 6:10 a.m. in the Polychrome Pass area where I had watched caribou and bears the previous day, I discovered a bear carrying a calf up a steep snow bank to the bench above the river bar. Apparently, the calf had just been captured because 14 caribou were trotting away from the scene, and a lone cow was maneuvering anxiously near the bear.
About 2 miles from this bear, another lone one was seen first striding along and then stopping to feed on a carcass. He may have known about this carrion and was returning to it.
Later, at 8:45 a.m., the mother and 2-year-old cub seen the previous day were discovered chasing rather half-heartedly a small band of caribou, and the mother soon gave up. As they traveled, they encountered four or five small bands of caribou but did not chase any. After about an hour, they veered to one side and fed for 10 minutes on a carcass they had discovered, then continued on their way.
At 6 a.m. on 3 June 1965 my attention was drawn to 15 caribou below us, galloping eastward on Polychrome Flats. They obviously were fleeing from a wolf or bear. Scanning the country behind them I discovered a grizzly 300 yards away, galloping in pursuit. Presently, he stopped and for about 10 minutes meandered about with nose to the ground over a patch of tundra 200 yards in diameter. In one spot he seemed to find a morsel that detained him for a couple of minutes. Finally, he dropped this project and walked out over the tundra, occasionally nipping at dwarf birch and willow tips.
When he came to a snowfield on a slope, he followed a bear trail to the top of the drift, then reversed his direction and followed the trail to the bottom, stepping in the tracks of the trail all the way up and back, not missing a single one. A lone cow caribou, lying in the tundra a little over 100 yards downwind from the bear, was watchful but the bear was unaware of her. She probably had a young calf nearby.
After lying in the snowfield for a short time, the bear walked steadily across the tundra for three-quarters of a mile. He galloped toward six caribou 200 yards ahead of him. They sped away and he turned aside toward four others who circled and then watched him from 75 yards away. There were no calves in either band. The bear wandered off and when I left at about 8 a.m., he was digging roots. Scattered, traveling caribou moved to either side of the bear as they passed by.
I saw three other lone bears during the morning. I watched one feed on crowberries on an old river bar. Another, that was traveling across a gravel bar near the head of a river, startled seven or eight caribou that trotted in a tight circle and stopped to watch him go by. A third bear was seen in foothills, feeding on crowberries.
In mid-afternoon I discovered the dark mother and her 2-year-old cub on a snowfield east of the East Fork River. They were moving east along a draw when they became aware of a herd of 30 or more caribou on the slopes about 300 yards above them. The mother started loping up the slope toward the caribou, the cub following 30 or 40 yards behind. The caribou hurried and were quickly out of view and far away. The bears continued loping up the rather steep slope for perhaps a quarter of a mile before the mother stopped. The cub caught up to her, and, enjoying the chase, loped ahead. The mother followed for a short distance then stopped, and both bears climbed out of view into a deep draw on the other side of a ridge. Soon I saw another group of caribou climbing a slope and surmised they had been startled by the bears. In their hunting the mother and 2-year-old had moved 3 miles beyond their usual range but the following day were back in their old haunts.
During the day, I had seen four lone bears on Polychrome Flats, and two families and two lone bears on Sable Pass. About 600 caribou had been seen in the area.
On 4 June about 1,300 caribou, in groups of various sizes, were distributed widely in the Polychrome Pass area. Four wolves spent the day resting on a gravel bar. During the day, five lone bears and a mother and cub were observed but their activity was so scattered that I missed some.
The dark mother and her 2-year-old cub, seen over the previous few days, were again on hand to exploit calf-hunting opportunities. I saw the family at 8:30 a.m. traveling on a gravel bar. As the mother became aware of six caribou cows, she and the cub loped toward them. There were no calves and the bears soon abandoned the chase. They walked across a gravel bar, climbed a bank, and, a short distance out on the dwarf birch flats, stopped to feed on a calf carcass. A concerned cow circled nearby, apparently the mother of the dead calf. The bears fed for 15 minutes, moved off to feed on crowberries for 5 minutes, and returned to the calf carcass where the mother bear rested and the cub chewed on remnants for one-half hour, after which the cub nursed. They both fed again at the carcass, apparently cleaning up the remains, before departing to rest on a snow bank for 1-1/2 hours. At 11:25 a.m. these bears became aware of a lone bear sniffing about where the calf carcass had been. They galloped to the top of a gentle rise to watch the lone bear who, finding nothing to eat, continued on his way. The mother apparently recognized the bear as one too small to worry about because she moved back to the snowfield before it left and nursed the cub again. They rested until 12:30 p.m. and then walked south a mile, watched a band of 15 caribou pass by, and fed on crowberries. In an hour they were back sniffing the spot where the calf carcass had been and then continued traveling.
On a flat of dwarf birch they came upon a herd of 40 caribou including 5 or 6 calves resting. The caribou sped away, but soon stopped to watch the bears loping toward them. Two of the cows with calves watched the mother bear until she was quite near. The mother bear must have been aware of the presence of calves for she increased her speed. One of the fleeing calves, for whom the dwarf birch brush made motion especially difficult, could not keep up with the others. When it reached a grassy lane, it managed to stay ahead of the bear but was captured when it turned aside. The 2-year-old cub was left far behind and had some difficulty finding its mother. When he located her, he approached cautiously and stopped often to stand erect on hind legs to look. The mother never once looked up to assure the cub, but fed hungrily. They both fed for three-quarters of an hour, then walked to a snowfield where the mother quenched her thirst with seven or eight mouthsful of snow. She loped easily toward a cow and calf that were passing but only followed a short distance. After a session of play, the bears returned to the carcass to feed and rest, then moved to a small stream where the mother drank and then returned to the carcass. When I left at 5:30 p.m., the mother was resting and the cub feeding. Later in the evening, I did not see the bears; apparently they were resting out of my view. The mother had captured one calf during the day, and possibly two.
At 7 a.m. the same day we saw a lone bear digging roots on a bar toward the head of East Fork River. A little later this bear started traveling and by 11 a.m. had moved 5 or 6 miles in a large loop and chasedall without success10 groups of caribou ranging in number from 3 or 4 to 150. During this time he did not feed.
Another lone bear seen early in the morning chased 200 caribou that doubled back around him and settled down on a river bar to feed and rest. Later he was seen chasing five bands of caribou, one after the other, without any luck. All these chases were similarthe caribou sped away rapidly, leaving the bear hopelessly behind.
Three other lone bears were seen briefly as they rested, traveled, or fed on crowberries and roots.
It was apparent that the bears were having more difficulty capturing the calves who were now becoming old enough to escape easily.
About noon on 5 June 1965 a lone bear was observed walking steadily toward a herd of about 150 caribou. When 200 yards from them, his walk changed to a slow lope. The caribou were not alarmed, for as he came close they moved off a short distance to either side and stood watching, thus forming an aisle for his progress. After loping easily through the middle of the herd, he spotted two cows each with a calf at the edge of the herd and shifted to high speed. One of the calves soon fell behind the other three caribou and was soon overtaken. After feeding on the carcass for an hour, the bear started walking in the direction from which he had come, toward foothills 2 miles away. En route he encountered a group of 20 caribou, loped after them until they turned to one side, and then resumed walking as before. Reaching the foothills, he climbed far up a slope and lay down on a rocky outcrop. This long retreat from the carcass to the cliffs suggested unusual caution. This behavior was like that of bears with cubs in spring.
On 6 June at 2:45 p.m. I discovered a blond mother and her blond yearling near the head of the west branch of East Fork River. They were traveling west and climbed one of a series of parallel ridges that come off the Alaska Range and terminate on the south side of Polychrome Pass. In the next 3 hours they climbed and descended four of the parallel ridges and climbed the fifth, traveling steadily except for one stop of 15 minutes to dig roots. Along the way they encountered several caribou. Forty caribou resting to one side of their path were startled and ran down the slope to one side, but the mother bear paid no attention to them. Coming over one ridge she frightened a herd of 30 caribou, made 3 or 4 jumps toward them, and resumed her travel. Near the top of the fourth ridge she encountered six cows and a calf and chased them to the bottom of the slope. Near the top of the fifth ridge, about 50 caribou were feeding in a basin. As the bear swung to the left, toward the caribou, I shifted from field glasses to telescope. During the few moments this took, she dispersed the caribou, and through the telescope I watched her walk up the far slope of the basin and stop to feed on a carcass. She was so far away that details could not be seen. A worried cow came over the top of the ridge and stood watching the bears feeding, apparently on her calf which had been too young to try to escape or had died earlier. The bears fed for about 25 minutes and then rested nearby.
The following morning, 7 June, I saw the mother and blond yearling a mile from where they had been feeding on a calf the previous evening. The mother of the calf was still near where the carcass had been. Soon after I saw the bears, they turned and loped 200 yards to feed for 10 minutes on a carcass, probably the remains of a calf. The family then traveled across the dwarf birch flats, startling a lone cow who pranced ahead of them with tail erect and twice sky-hopping. The bears ignored her. At 7:30 p.m. the bears galloped at right angles to their course toward two cows who circled and trotted up close to the bears, then trotted off with tails erect. The bears sniffed around where the cows had been but found nothing. Farther on, five more caribou watched the bears who seemed to have found the remains of a carcass for they fed for 35 minutes. One hundred and seventy-five caribou were scattered about on the flats.
On the afternoon of 7 June 1965 a lone bear loped after 15 cows and 6 calves that quickly left the bear far behind. Soon afterward this bear encountered a lone caribou and chased her briefly. Later in the day we saw a lone bear chase three cows for a short distance. A few chases occurred during the day but there were no captures. During the following days that the bears were observed, a few chases occurred, but no kills. Most of the calves were apparently strong enough to escape the bears and, as the 1965 calf-hunting season was over, they had to wait until next year before again hunting calves (Fig. 46).
Every spring the drama of grizzly bears supplementing their vegetarian diet with young caribou occurs in the tundra. This is an old relationship, one of the natural ecological activities still existing in McKinley National Park. Those grizzlies living on the migration route that caribou use during the calving season capture a nominal number of young animals, but even in years when grizzlies find exceptionally good caribou hunting, their activities have little impact on the caribou population.
A mother moose with one or two calves is formidable, even to a grizzly. During the last half of May and early June (the calving period) the grizzly, and also the black bear, consider a moose calf potential food. However, the mother moose is not easily daunted and can often discourage a bear by her belligerent presence. Individual behavior varies in both moose and bears when confrontations occur. I expect that a large male grizzly is less easily deterred than is a smaller bear (Fig. 47).
The mother moose may slip away prudently with her calf when it is a few days old to avoid a bear she has discovered in the neighborhood. There is, of course, the possibility of a bear finding an unguarded calf and capturing it before being discovered by the mother. In Wyoming in mid-June Conley (1956) saw "a black bear carrying a squealing calf moose in his mouth. Almost immediately a cow moose appeared and attacked the bear. She jumped on the bear's back, striking him with her front hooves. The bear dropped the calf and turned to fight the moose." Conley shot the bear, ending the incident. A little later the cow and calf could not be found. The bear was 6 feet 9 inches in length and weighed 350 pounds. The moose had inflicted a deep gash in the bear's shoulder with her hooves.
The belligerence of the cow moose is illustrated by an interesting observation made by Altmann (1956) about a band of horses seen in June swimming to an island in the Snake River (Wyoming) to feed.
The respect that grizzlies and moose have for each other tends to keep them apart after the calving period. I have no record of a grizzly killing an adult moose in the park, but in Wyoming others have reported bears killing adult moose in the spring, floundering in deep, packed snow through which their long legs break and slide downward at unpredictable angles that cause them difficulty. A short, vigorous struggle of this kind might soon exhaust a moose weakened by a long, hard winter, but ordinarily such snow conditions are not known in McKinley National Park.
The effect of bear predation on moose populations is difficult to determine, but moose in McKinley National Park have prospered in spite of a large grizzly population. Predation on moose calves is sporadic because calving takes place over a vast acreage, and even a bear trying to kill a calf seems infrequent. Some bears are busy with their root digging and seem unaware of the potential.
The following incidents that I have observed in McKinley National Park illustrate the behavior that may occur when grizzly meets moose.
Cow Moose Keeps Bear at Bay
Elsewhere (Murie 1961) I have described the behavior of a moose guarding her two calves, and how she kept a large grizzly at bay successfully.
Bear Captures Calf
In June 1962 a bus driver saw a bear chasing a cow and calf along Igloo Creek and watched the bear capture the calf and drag it into the brush. The cow continued running, not realizing that her calf had been captured. No other details were observed because the bus continued on its way. This incident was complicated by the appearance of the bus on the scene and the retreat of the cow.
Large Bear Kills a Calf
On about 1 June 1961 a park workman saw a bear that he thought was a big male kill a calf. His car almost ran into a cow moose with two calves and a bear chasing one of them. He backed away from the animals and the conflict moved toward him as he continued to back away for "about a mile." The cow struck at the bear with front feet, and the bear stood on hind legs to strike the moose with a paw, but apparently no contact was made. The bear finally succeeded in killing one calf and carried it into the brush near the road.
Cow Moose Retreats From a Large Male Grizzly
On 21 May 1961 I saw a cow moose with two newborn calves and, 60 yards away, her unwanted yearling. They were in a willow depression near the base of a steep incline on Polychrome Pass. It seemed an ideal nook, away from travel routes, in which to be sequestered with the calves until they gained strength.
On 26 May a lone, 3-year-old grizzly moved down the steep talus slope above the moose. The noise of rolling rocks alerted the mother. When the bear saw the moose, it turned at right angles and, with what seemed a cautious and watchful attitude, followed a contour above. When he had passed the moose, he broke into a gallop and descended the slope at some distance to one side of the moose. His anxiety caused him to continue galloping for half a mile after reaching the flats at the base of the slope. When the yearling moose saw the bear, it took fright and hurried down the slope to the flats, moving out on the tundra. The cow and her twins moved only about 30 yards down the slope. Apparently this mother had estimated correctly the size of the bear for she did not seem frightened or even apprehensive.
Three days later, on 29 May, the mother moose and her twin calves were in the same retreat. Out on the tundra a large male grizzly was on the move, no doubt in search of a receptive female. He disappeared from view on the river bar below me. When I saw him again, he had climbed the slope and was on the edge of the little basin where the moose family was staying. As I watched the bear moving forward, only 40 yards from where the family had been resting, it appeared that a serious altercation would take place. But about that time both the bear and I noticed the cow and two tiny calves climbing the long steep talus slope leading up to the road. The cow apparently had moved off as soon as the bear came to the edge of the basin, or perhaps a little before. Because of the willow growth and the lay of the land, it is possible that she had seen the bear when she started to leave, but she also may have scented him and started to leave before he was in sight. The yearling moose was not present. The talus and large rocks and the steepness of the slope made climbing difficult for the cow and calves. The bear started climbing after them but they had a good start and were able to reach the road while he was climbing slowly, far below. The family moved down the road away from my car; when the bear reached the road, he came toward me instead of following the moose, and on seeing me climbed to the skyline above and disappeared.
The reaction of the moose to the big male was far different from her behavior at seeing the small bear a few days earlier. In the second incident she seemed to know that a large bear was approaching and retreated discreetly with her calves.
Male Grizzly Feeds on a Young Calf
On 25 May 1962 I watched a 3- or 4-year-old bear near the top of a pass between Igloo Creek and Big Creek. He crossed several low ridges and followed one leading toward a cow moose, who stood immobile except for cocking her ears occasionally toward something on the ground nearby, no doubt one or two very young calves. The bear stopped abruptly about 75 yards from the cow, stood watching her briefly, then retraced his steps, recrossing the ridges over which he had come. A little later I saw a calf beside the cow. A yearling moose appeared from the direction the bear had gone and trotted to a point 150 yards from the cow moose who, no doubt, was its mother. The cow climbed toward the yearling with ears held down threateningly and angrily, and when she was near, she ran and struck at it with front hooves as it retreated. Later, after she had returned to the calf, she again chased the yearling who did not wish to leave its mother.
About one week later (2 June) I saw a large, male grizzly lying where I had seen the cow moose with her calf. The cow was moving about anxiously in the vicinity, coming to within 40 or 50 yards of the bear, who would raise his head slightly each time she approached. This situation continued from 5 p.m. to 10 p.m. Once the bear walked down to the creek for a drink but returned to his resting spot. The cow, when I left, was almost on Igloo Creek, one-third mile from the bear. The yearling was at first present but later disappeared.
The following morning at 5:20 a.m. the bear was still lying where I had seen him the previous evening. Soon he stood up and yawned, and moved down to the creek and out of sight. The cow moose was 200 or 300 yards from him. At 3:30 p.m. she was on Igloo Creek and at 4:15 she was lying down. At 7:15 p.m. she was in almost the same place. The big bear had no doubt disposed of her calf. The small bear had not dared approach, but apparently the big male had moved forward, and the cow had retreated.
Male Grizzly Undaunted
On 17 May 1961 I spent a few hours watching a pair of mated bears along the East Fork River. When first seen the bears were lying down on the open tundra. During the next couple of hours mating maneuvers took place between them. The male also spent some time following a trail, then again turned his attention to the female.
About noon he stopped bothering her. He raised his muzzle, catching an attractive scent. He climbed a bluff at the edge of the river bar and entered a shallow, brushy depression where he fed, obviously on a carcass because he fed in one spot and I could see that he was tugging at something. I think he had followed earlier the scent left by a fox or wolverine carrying away part of the carcass. Now at last he was at the source. A cow moose now appeared, hackles up as she approached the hollow where the male was feeding, but after a brief look at the bear she trotted away for a quarter of a mile. She repeated this performance twice more, and after the last time, moved up the river for one-half mile. The bear took little note of her and after her last retreat, he apparently had finished the remains, for he moved down to the river bar. Later the cow returned to the hollow, circled it, and finding the bear gone, entered the hollow, where she moved about, nosing it thoroughly. After 15 minutes, she left, but returned three more times to investigate, no doubt hoping to find her calf. Once when she approached, a fox ran out of the hollow. The female bear remained out on the river bar digging roots; apparently she was unaware of the carcass, perhaps being too far out on the river bar to catch any scent. The cow moose was seen 2 days later as she walked a half mile to the hollow where her calf had been eaten. This episode showed that a large, male grizzly could hold his ground in the presence of an angry cow moose.
Cow and Her Yearling Move Away From a Bear
On 18 May 1961 I saw a fairly large grizzly gallop easily across the tundra and enter an extensive patch of willows. A cow and her yearling came out of the willows near where the bear had entered. They trotted away, apparently not frightened but disliking the proximity of the bear, especially in view of his hurried arrival. As I moved nearer, I saw the bear near the edge of the willows feeding on a caribou calf. I did not observe enough to ascertain the circumstances concerning the calf's death, but it seems certain that the cow moose had no calf because she still was tolerating her yearling and gave no indication that she was leaving a calf. Even when no spring calf is involved, it seems that cow moose tend to avoid bears.
Cow and Calf Leave Vicinity of Bear Family
On 19 July 1963 a mother bear and her two 2-year-old cubs were moving north near the base of Cathedral Mountain. A cow moose followed by a calf trotted away about 300 yards ahead of the bears. The moose had left a rendezvous in the willows not far from where the mother bear was waiting for her cubs to leave a fox den. The three bears shifted into a slow lope and trailed the moose. Four sheep that were farther up the slope saw the bears and climbed a little higher, probably not worried so much by the presence of the bears as by their loping gait. The moose disappeared over a rise and the three bears turned, after traveling about 300 yards, and crossed Igloo Creek. The mother bear did not seem too anxious to overtake the moose. The moose only seemed to serve as an excuse for a playful romp, a sort of make-believe chase.
Cow and Calf in Late Summer, Unafraid of Small Bear
On 30 August 1959 I saw a cow moose with a calf on a dense willowaspen slope below me. Before she and her calf trotted a few yards and went out of my sight she was watching intently something above her. A few moments later I saw a whitish object in the aspens, a cream-colored grizzly, about 4 years old, with brown face and dark legs. Soon the cow moose and her calf returned to where they had been, and after watching the bear a few minutes, browsed in the willows. A little later she and the calf lay down. The bear continued to feed on the slope above her. The moose may have noted its small size and regained her composure, or she may have recognized the bear as one she had seen often and did not fear.
Belligerent Moose Attacks Bear
On 14 May 1961 I stopped near Hogan Creek to watch a medium-sized bear walking west across a hillside of scattered spruces. Ahead of the bear I caught a glimpse of a cow moose, walking toward the bear. Her ears were cocked forward; I guessed she was bent on intercepting the bear, and I was right because a little later I saw the bear making a dodging, scrambling effort to escape, the angry cow galloping close upon his heels and about to strike him with every jump. The bear made a sharp turn as he disappeared from my view and the cow followed, but did not turn quite as sharply. I did not see the bear again, but the cow returned, trotting briskly down a ridge to the road and into the tall willow brush. Once she stopped with ears cocked as though looking for the bear. Soon she climbed the slope, obviously still agitated. A short time after disappearing into the spruces, she reappeared on the open tundra, walking slowly, followed by a tiny calf still unsteady on its feet.
Cow Moose Chases Grizzly
On 1 June 1961 at 11:30 a.m. I stopped to watch a medium-sized bear, a female or young male, as it stood on an open knoll gazing down at a small patch of tall willow brush in a depression. Five minutes later the bear walked down the slope and entered the willow patch. A few moments later a cow moose rushed out from the willows on the lower side and the bear emerged from the point where he had entered. This behavior suggested that the bear had startled the moose, and the noise made by the moose in dashing out of the willows had startled the bear. The bear lay down on the slope, and the moose maneuvered slowly on her side of the willows with ears cocked toward the bear.
Later, the bear walked to the edge of the willow patch and lay down where the willows were less dense. The cow walked slowly toward the bear and as she neared him made a determined dash, causing him to retreat rapidly up the slope. The moose then walked into the heart of the willow patch, where for a time I occasionally could see her as she reached high to browse on willow twigs. An hour later the situation had not changed except that the moose could no longer be seen; apparently it was lying down. The bear moved 200 yards up the slope and lay down for over 2 hours. After that, he fed on the new growth of grass (Calamagrostis). When I left the area at 5:30 p.m., the bear was feeding on roots. A few days later I examined the willow patch for traces of calf remains but found none.
A Yearling and Its Mother Flee from Three Moose
On 9 September 1961 on Sable Pass I watched a dark mother bear and her yearling cub feeding on berries on the far side of a creek bottom where tall willow herbs grew. I heard a grunt in the willow patch and the two bears heard it also. They stopped feeding to watch, part of the time standing erect on hind legs. Soon a cow, calf, and a young bull moose emerged from the heavy growth of willows and moved a little closer to the bears, obviously unaware of them. The cub was getting nervous, moved to the far side of its mother, then retreated 10 yards, and stood erect to watch the moose. Suddenly, the cub was overcome with fear and fled, and the mother followed finding it difficult to keep up with her cub. After galloping a quarter of a mile, the mother bear halted and the cub, still ahead of her, stopped also, but he still was very anxious. The mother probably would have moved aside a short distance if the cub had not dashed away.
Bear Family Avoids Bull Moose
On 7 September 1962 I watched a bull moose thrashing vigorously at willow brush with his antlers. A mother bear and her two yearlings, who were foraging in a ravine 75 yards below the bull and unaware of his presence, heard the noise and became wary. After listening for a moment, the mother bear led the way down the slope at a steady walk and crossed a little creek a quarter of a mile away before resuming her foraging (Fig. 48).
Bull Moose Frightens Two Yearling Cubs
On 25 September 1963, when bulls were searching for cows, I saw a mother grizzly and her two cubs cross Igloo Creek and climb onto a bench. The mother in feeding soon went over a rise, but the cubs remained in view, feeding on berries. Soon I saw a bull moose walking rapidly on the creek bottom toward the bears. He climbed the slope and came close to the cubs, who, on seeing him, hurried away in the direction their mother had taken. The bull apparently had seen or heard the cubs in the distance and mistaken them for cows. Realizing his mistake, he moved slowly along a contour, grunting intermittently.
Cow Chases Two Bears
On 3 June 1964 a cow moose was standing on a low pass just south of Cathedral Mountain, gazing fixedly toward the Teklanika River. Nothing was in sight so it appeared that she had a scent of something that disturbed her. For 5 minutes she stood watching before she resumed browsing. A few moments later, two bears came over a rise from the direction she had been watching and pursued a course which would take them to one side of her. They appeared to be 2-year-old cubs that I had seen with a female 3 days earlier. As they approached, they stood erect on hind legs three times to look around. They behaved as though they were looking for something, perhaps their mother. They saw the cow moose when they were about 100 yards to one side of her, and loped exuberantly forward. I guessed that they thought the bulky form in the willows was their mother. The cow moose saw them coming and charged. The larger of the two bears veered northward, with the cow moose in pursuit. The cow struck at the bear with a forefoot, but the blow fell just short of his rear. The cow then stopped and, seeing the second bear circling, dashed after it, causing it to flee in the opposite direction. She halted only when she came to a snowfield. The first bear was now circling back to join his companion and the moose chased him again, almost overtaking him before she stopped. After the bears disappeared over the nearby slopes, the moose returned to where she had been, and a small calf appeared out of the brush to nurse. (I learned later that there were two calves.) The cow unhesitatingly had charged two grizzlies. Would she have been as fearless if the bears had been larger, and would a large bear have run away? Possibly a large male would have stood his ground, but in the face of a charge he may have been at a psychological disadvantage and retreated; in addition, the cow might have been less bold if a large male bear had been present.
Cow Moose Chases Lone Bear
On 5 June 1965 about 7 a.m. I saw a cow moose on the edge of an extensive patch of willow brush, and about 100 yards from her a blond, medium-sized bear lying on his stomach, head on paws, watching the cow. Two days before, I had seen the cow at this location with a small calf, and one day before I had seen him a mile from where he now lay.
The cow watched the bear for a few minutes then walked along the edge of the willows. She appeared to be checking on her calf. She turned and walked toward the watching bear, her ears cocked toward him. He saw her approaching and retreated at a walk, and when she started trotting after him, he galloped down the gentle slope. She chased after him, stopping two or three times, and the bear stopped also. After each stop, she would gallop toward him. This continued for a quarter of a mile before she quit the chase and returned to the starting point. The bear continued traveling toward a band of caribou, which he chased briefly. I left the moose standing where I had first seen her that morning. When I returned a few hours later, she was standing in the open as before. Soon she walked eastward, away from the willow patch, and continued for about a mile; then she turned and came back, trotting part of the time. On her return she entered an isolated willow thicket and rested for 2 hours. There was no calf with her, and I suspect that she had lost it, because the following day I saw her leave the area and travel westward for a mile, apparently leaving the area. Perhaps the bear had come upon her calf while she was feeding a short distance away, and killed it. But the calf may have died at birth or been killed by another bear or a wolf, and the young bear may have wanted to feed on what remained of the carcass (Fig. 49).
Moose Chases Grizzly and Wolf
On 27 May, my first day out in the park in 1967, from the road near Hogan Creek, I saw a cow moose and her two recently born calves resting high on a gentle, treeless slope of Primrose Ridge. Near the base of the ridge, a short distance above the road, the carcass of a bull moose was attracting grizzlies and other meat eaters. A grizzly mother and her two 2-year-old cubs were resting on a snow patch 150 yards above the carcass on which they had gorged.
While I watched from a vantage point, two photographers began climbing toward the bears, but before they came in sight, the mother bear retreated up the slope at a slow, deliberate walk, and the two large cubs followed. The photographers soon returned to the road.
The cow moose became aware of the approaching bears when they were a quarter of a mile down the slope. Standing like a statue, big ears cocked forward, she watched. The bears appeared to be unaware of her dark form silhouetted above them, but the mother bear swung slightly to the left as she neared the moose, enough to bypass a hundred yards to one side. Not until then did the bears show any indication of awareness. They stopped, turned their heads for a momentary look, then continued on their way and lay down 300 or 400 yards from the moose, who also soon relaxed and lay down. I learned from the photographers that they had seen this moose with her calves in the same spot the previous day and had watched her chase the three bears as they came near her.
The following morning at 4:45 a.m. I discovered the mother bear and her two cubs high on Primrose Ridge, walking down the slope and passing 75 yards to one side of the cow moose, while she stood watching them. The bears were walking rapidly as though hungry and in a hurry to arrive at the carcass. At 5:10 a.m. the bear family approached the carcass and remained there for about 2-1/2 hours, then moved and lay down on the far side of the creek.
At 9 o'clock the mother bear nursed her cubs and at 10:50 a.m. the family walked up the slope of Primrose Ridge again, at first following the draw they were in where the winter snow lay deep. In half an hour the bears had reached the spot where the cow moose and her two calves had sojourned for at least 2 days. The moose had left the spot soon after the bear family had passed by in the early morning and had gone 400 yards with her calves before stopping. Later, she went over the horizon, how far I did not know. The bears examined the spot where the moose had been briefly and then followed the moose trail at a brisk walk. Soon the bears started loping, the trail apparently making them eager, but before the bears reached the skyline, the cow moose appeared charging the bears, who fanned out and galloped away to avoid hooves. The cow stopped for a moment, then charged again, chasing the bears in a semicircle to some cliffs behind which they disappeared. The cow returned to the spot where she had appeared on the skyline and stood alert, watching in another direction.
Later, I saw a grey wolf approach at a trot within 25 yards of the cow. When she took a few threatening steps, the wolf retreated 10 yards. This was repeated five timesonly a slight movement was sufficient to cause the wolf to retreat. The wolf then lay down 40 yards away, but in 5 minutes it trotted off. I left the scene at 2 p.m., but later in the afternoon it was reported that the moose chased the bears and the wolf again.
My observations on grizzlymoose relationships indicate that a cow moose can and will protect her young against bear attack, at least if the bear is not too big. There is some indication that a full-sized, male grizzly may be difficult for the moose to chase away.
It is obvious that the grizzly occasionally captures a calf and that the grizzly is a balancing factor affecting numbers of moose.
GrizzlyDall Sheep Relationships
The sheep hills are an integral part of the grizzly's home. He uses the slopes for much of his ground-squirrel hunting, root-digging, berrying, denning, and traveling. Because they use the hills jointly, he and the sheep are well acquainted. Each has evaluated the physical prowess of the other and weighed it against his own. The grizzly's knowledge makes it unnecessary for him to squander time and effort in a futile pursuit of sheep if he lacks the advantage, which he generally does. Sheep also are able to judge well the degree of their vulnerability when meeting grizzlies, and so are spared becoming unduly apprehensive. Serious encounters are uncommon. Only occasionally does a grizzly have the opportunity to capture a lamb, and even more rarely, an adult. Because the grizzly is a potential enemy and the sheep potential prey, each plays a part in the life of the other (Fig. 50).
The sheep enter the bear's diet chiefly as carrion. The extensive wanderings of grizzlies in early spring no doubt take them occasionally to the remains of a winter kill sufficiently intact to furnish some food.
Although bears, and sheep to some extent, feed on berries, competition is insignificant because in most years enough berries are available for all unless a drastic berry failure occurs, and then there is little for anyone. On one occasion I did see what might be termed some direct local competition for berries, when 131 migrating sheep crossing the Toklat River stopped in one of the grizzlies' favorite buffaloberry patches and fed extensively.
Sheep Alert to Presence of Grizzly
The behavior of sheep may call one's attention occasionally to the presence of a bear, for when a bear is sighted sheep often stop feeding and watch. If he is distant, they may resume feeding; if nearby, they may watch until he has passed or make a precautionary move up the slope and then resume feeding. A running bear causes more concern than a feeding bear, which is likely to receive only perfunctory attention. On 6 September 1963 I saw 70 ewes and lambs move up into cliffs when they saw a mother bear followed by a spring cub galloping and hunting ground squirrels on a contour far below them. On other occasions I have observed sheep reacting similarly upon seeing a bear loping away from a man.
I frequently have observed sheep close to bears without showing much concern. In 1953, four of us climbed Sable Mountain to look for White tailed Ptarmigan, to observe the fall coloring of herbaceous cinquefoil and other herbs, and to enjoy this unspoiled, wild country. We saw four sheep following a ridge in our direction, and, thinking it would be interesting to watch them pass close by, we remained hidden behind a light, rocky prominence. While we waited, a grizzly appeared over a side ridge from the opposite direction, traveling our way. When the grizzly and the sheep were opposite each other, a little above us, the grizzly changed course slightly, veering toward the sheep which moved to one side and a little higher on the ridge, watching while the grizzly continued traveling, passing between us and the sheep. The sheep appeared to feel no danger, and the bear apparently sized up their situation in the same way.
On 25 May 1955 I watched a female and two 2-year-old bears climb a slope near Savage Canyon. When they neared a band of 33 rams, the mother made a short run toward them. The rams fled upward about 100 yards, then walked slowly a little farther, and stood watching the family pass over the ridge a short distance from them. In rough country the sheep are aware of their security.
On 24 May 1963 I watched a ewe and lamb move across a rather gentle slope on Cathedral Mountain and then discover that they were below a mother bear and two 2-year-olds who were busy digging roots. The ewe recognized her position as vulnerable and galloped rapidly across the contour below the bears and up the slope to the other side. Here, although still not far from the bears, she felt safe.
The following day I saw on the same contour a young ram approach the three bears who were digging on the same gentle slope. He stopped to watch the bears when about 75 yards from them, then turned and moved slowly up the slope to one side, soon confident in his safety, for rugged cliffs were nearby.
Migrating Sheep and Grizzlies
When sheep, in migration, pass across long, gentle stretches of terrain such as valleys and river bars, they are vulnerable if they are discovered by a wolf, and probably are somewhat vulnerable to attack by bears. There have been three or four incidents described to me in which migrating sheep in the Toklat River area were hard-pressed to escape a bear. On one occasion a bear cut a ewe off from the main band and nearly overtook her as she crossed a spring snowfield. Fortunately for the ewe, she managed to cross the snow and gain nearby slopes where she had the advantage (Fig. 51).
On 8 June 1961 I expected to see an exciting incident when I observed two ewes, each with a lamb, crossing the wide Toklat River bar on their way to Divide Mountain. They were headed straight for a big male grizzly and his mate who were on the bar digging roots. But the sheep veered to one side of the bears, which they could not see because of scattered willow brush, and crossed without incident. If they had met the bears, it is possible they would have had some difficulty escaping.
Behavior cannot always be predicted. On 22 September 1961 I watched a young bear, perhaps a 3-year-old, traveling down the Toklat River bar near the forks. As he proceeded, he approached a group of about 60 ewes and lambs that had scattered widely over the river bar, feeding as they crossed. Although some of the sheep were watching the bear, when he was 200 yards away they did not take flight as I expected. The bear must have seen the sheep, though from his actions I was not sure that he had. Possibly this young bear was not perceptive enough to realize that the sheep were vulnerable, and so paid no more attention to them than if they were in cliffs. He went about his business as though they did not exist, turned aside to sniff a squirrel hole, and a little later made a right-angle turn; in a few minutes he was lying on his back scratching himself. The lack of concern that the sheep showed was harder to explain. They walked down the bar away from the bear and continued for 200 or 300 yards before stopping to feed again, but I expected more concern. If the bear had given chase, I think the sheep could have crossed the bar to safety but they did not seem to take their usual precaution to insure maintaining control over the situation with room to spare.
Bear Captures Newborn Lamb
On 21 May 1949 along Igloo Creek a group of men were working on the road and saw four ewes and a newborn lamb in a draw almost at the bottom of the creek. One of the men approached the sheep to take a picture. When he was ready to take the picture, a bear galloped down the slope toward the sheep and the photographer. The photographer escaped with long strides across a snowdrift, but the newborn lamb, after a chase of a few yards, was captured quickly and devoured. The photographer thought the bear was charging him and was diverted by the sheep at the last moment; the spectators believed that the photographer was incidental and that the bear had the sheep in mind all the way down the slope.
On the following morning when I came upon the scene, the bear was some distance up the same slope digging roots. The mother sheep was lying near the spot where she had lost her lamb. In about 20 minutes the bear walked slowly down the slope toward the ewe, who now stood up and picked her way along a low rim bordering Igloo Creek. The grizzly followed her trail and stopped now and then to paw out a chunk of sod to get at peavine roots. His interest in the ewe persisted, with good reason. The ewe's rear was bloody, and about 8 inches of afterbirth still dangled. No doubt a little blood was in her trail, enough to encourage the bear. Shortly before the bear arrived at the fox's den where the ewe was now lying, she stood up and picked her way down the rocks at the point of the ridge. The bear came to the point directly above her, so close it seemed he might have rushed her successfully, but he came slowly down one side, and by that time the ewe had crossed a sidestream by clambering through deep snow. She was soon on a long ridge leading up Igloo Mountain, and the bear, after following for some distance on the ridge, gave up and returned to digging roots.
The evidence indicates that this incident developed from special circumstances. Normally, the lamb would have been born high in the cliffs where it would have been well protected. The prolonged retention of the afterbirth suggests an abnormal birth, and a weak lamb perhaps, causing the ewe to drop the lamb in the unprotected spot near the stream.
A Fortuitous Incident
On 27 May 1950, I just missed seeing a grizzly capture a lamb. I stopped to classify a group of ewes and lambs resting on a sharp, grassy spur ridge on the south slope of Igloo Mountain. A short distance below this group, two additional ewes and a lamb were grazing. After classifying the sheep, I drove down the road and stopped for a look at the other side of the ridge to see whether any sheep were resting beyond my first view of them. While I watched, the group I had classified galloped into view and crossed a shallow ravine. This seemed rather unusual, for I had seen nothing to alarm them. I thought they might be frolicking. I drove back up the road, saw the two ewes and lamb still grazing, and decided they had been frolicking. About 5 minutes after I left the scene, a road worker came by, heard a mother sheep bleating, and saw a bear feeding on a lamb out on the open slope. The bear had escaped my observation and also that of the three undisturbed, grazing sheep. The uneven conformation and sharp contours of the slope below the ridge apparently made it possible for the bear to approach within a few yards of the sheep without being seen by them, and the lay of the land had kept the bear out of my view. I saw the mother sheep near the scene the following day, and on the next day saw her traveling in high cliffs, occasionally stopping to look down at the ridge where her lamb had been lost.
Trailing Lamb Captured
On 7 June 1963 a large group of ewes and lambs was feeding near the north end of Cathedral Mountain. I spent about 2 hours photographing them as they crossed two spur ridges. When I came back over the second spur, I saw a mother grizzly with two spring cubs on the adjoining ridge where I had first started photographing. Only a narrow, shallow draw was between us, so I angled down the slope to get out of her way. When I looked again, she was galloping at top speed down the slope directly toward me. I was dumbfounded, but fortunately she was not after me, but soon overtook a very young lamb. A ewe, a yearling, and this lamb had crossed Igloo Creek earlier, and naturalist Verde Watson had seen them closeup. He said the lamb seemed quite young and weak because it lagged behind the ewe and yearling. When the bear started the chase, the lamb tried to angle up the slope but then, perhaps because of weakness, turned and ran directly down the shallow draw where the bear captured it quickly. The bear fed for about 10 minutes at the spot where the capture was made, and then carried the carcass 15 yards up the slope and finished it (Fig. 52).
The following morning she left her bed soon after 5 o'clock and dug roots nearby for half an hour. She then climbed over the top of the ridge and went out of sight into a basin. From this basin emerged a canyon where I earlier had seen the big herd of ewes and lambs, scattered widely as they fed. To watch what happened when the bears arrived, I returned to the herd of sheep. Soon, a dozen lambs up the slope apparently saw the bear, for they watched in her direction and then started moving away slowly. Some ewes lower down behaved as though they too had discovered the bears. Then I saw the mother bear galloping rapidly on a contour toward some sheep bunched up ahead of her at a slightly higher elevation. The bear rounded a shoulder, galloped up the steep slope a short distance, then stopped to look around. She seemed aware that opportunities for capturing a lamb might exist. Turning, she galloped up the slope a short distance toward the main group, then stopped, realizing it was hopeless. The sheep soon returned to normal activity as the mother bear moved to one side and dug roots. This bear, because of its good luck the previous day, probably was more optimistic than usual.
He "Had It Made" and Didn't Know It
On 27 August 1963 I watched a band of 73 ewes and lambs feeding on a low, gentle slope of Sable Mountain. I noted that one of the lambs had difficulty lying down and walked stiffly. It was obviously ailing. Soon, I saw some of the sheep that had been feeding to the east of the main group run up the slope and stop to look eastward. Across a narrow draw, about on the same level as some of the sheep, I saw a dark grizzly walking steadily along a contour in the direction of the sheep. I estimated that he was 3 or 4 years old. Because of a short, new coat he seemed especially rangy. As he emerged from the draw, the sheep that had seen him angled westward and higher up the slope. When the bear was about 300 yards from the main herd and the sick lamb, now lying 30 yards below the others, he stopped to investigate some squirrel holes, but he soon moved forward again. When the main herd saw the bear, they galloped en masse westward and upward. The bear, upon seeing the general flight, loped forward. He was slightly above the sick lamb and perhaps 150 yards from it. The lamb got to its feet and, spurred by fright, galloped away rapidly, at first on the contour, then, being weak, turned down the slope. In full flight he collapsed and lay in an inert heap. Upon seeing the lamb collapse, the bear stopped and seemed puzzled. After watching for perhaps a minute, he did not hurry to the lamb, but turned slowly as though questioning what he should do, then loped back over his trail to where I first saw him, and walked steadily down the hill out of my view. Apparently, he was an inexperienced bear overwhelmed by the flight of the many sheep and the unusual and dramatic behavior of the sick lamb. He played it safe and retreated. It was a case of the elimination of the weak except that the inexperienced bear failed to play his role.
Bear Captures Yearling Sheep
About noon on 23 May 1964 I saw a fairly large blond bear arrive at a snow-free strip on the crest of a ridge. Tracks behind the bear showed that he had been traveling on a contour across snowfields that lay between low parallel ridges leading down to Igloo Creek. The bear had stopped to look around before starting to walk down the ridge he was on. Soon he stopped again and gazed steadily at an angle toward the creek below. Following the direction of his gaze, I saw a cow moose 250 yards from him, moving along the edge of the bench. Below the bench the slope dropped off some 30 yards to the creek bed, which was still covered with winter snow and ice. Following 50 yards behind the moose was a yearling sheepan unusual combination. Their tracks in the snow showed that they had moved down the ridge, starting from an area near the spot where the bear was standing. The moose moved diagonally down the slope; the yearling sheep traveled along the bench, toward the moose. Evidently, they had both seen the bear coming along the contour and had retreated to avoid him. A ewe was still up on the ridge out of sight of the bear and only a short distance leeward from him, and neither was aware of the other.
The bear now loped easily down the slope toward the moose and the sheep, who were moving along the bench and out of my view. (I did not go forward at once for fear of intruding on the situation.) Apparently, the bear was approaching them at this easy lope to investigate rather than with an immediate expectation of a capture. Halfway down the slope the bear stopped briefly to look, then continued as before, loping through the deep snow, until he too was out of my view. In a few minutes I had moved forward far enough for a good view. The moose had disappeared down the valley. I saw the bear dragging the yearling off the creek bottom and up the steep slope. As the bear moved up the slope, the carcass dragged to one side or the other and sometimes between his front legs.
Apparently, as the sheep started down a cliffy portion of the slope, it collapsed, rolled, and dropped off a perpendicular part of the cliff. Patches of hair clung to the brush where the sheep rolled down the slope. A bloody depression in the snow showed where the sheep struck the creek bottom and the bear, coming down to one side, killed the sheep. If the sheep had been in good health, it probably would not have retreated to the creek, or it would have been able to cross the creek and escape up the far slope.
When the bear reached the top of the bench, he dropped the carcass and walked a few steps to the edge of the bench to survey the creek bottom. Returning to the carcass he began to dine. first biting mouthfuls of hair from the hide to get at a hind quarter. Much of the time he sat on his haunches as he fed.
After eating for 45 minutes, he started pawing debris and sod toward the carcass and over it, using slow, deliberate strokes with one forepaw at a time. Two magpies discovered these activities and came as close as they dared for tidbits. In an hour the carcass was well covered with a mound of debris and the bear was lying beside his treasure. I left and returned a few hours later (6 p.m.) to find him lying on top of the cache which had been heaped up higher during my absence.
The following day, the 24th, a storm and drifting snow prevented me from returning to look for the bear. On the 25th I did not see the bear but saw his tracks and fresh droppings containing sheep remains.
On the afternoon of the 26th I found the bear picking away at the sheep skeleton, feeding lackadaisically for an hour. Two magpies, old friends by now, paid him a brief visit. The bear walked slowly away for 20 yards and lay down for 3 hours. During these 3 hours he rested in a variety of positions, reclining on back, stomach, and both sides, with variations of each. For a time, on his back, he rested like a female nursing young, with head raised so as to see nursing cubs if there had been any.
Toward the end he became restless, changing his position often. As he departed, he ate a few mouthsful of snow, and looked around as though wondering what he should do. Then he waded 100 yards or more northward through snow, made a wide arc, retraced his steps in the arc, and walked hurriedly to a bare spot on a ridge where two magpies were picking at a bone. He chewed on some scattered pieces on the bare spot, then out in the snow he uncovered what appeared to be the carcass of a calf moose. Suddenly he became alert, stepped forward a short distance, stopped, and peered into a canyon (out of my view) for 5 minutes. Possibly the mother of the calf was in the canyon. He fed for 1-1/2 hours, pulling small pieces of meat and tendons from the bones.
The next day (27 May) I saw the bear approach the sheep carcass from above, wading in deep snow. When in view of the cache, he stood watching for 4 minutes, probably to learn if another bear was in the locality.
At the cache he lay on his stomach and fed, pulling meat and sinew from the bones. Each tough little morsel was given 30 or 35 vigorous chews. After a time, he was pulling tidbits from pieces of hide. He pawed at the debris he had used to cover the carcass as he searched for pieces too insignificant to notice in earlier days of plenty. After 1 hour and 10 minutes, he lay down on the debris. During the next hour, the bear moved off twice to eat snow. After another half hour of resting, he yawned three or four times with tongue stretched out and forefeet forward. He sat for 8 minutes testing the air. It was a warm, sunny, quiet day. After departing he soon returned to the cache, contemplated it, and yawned some more. Soon he was chewing bones and pulling loose tough sinews, chewing each bite 70 or more timesthe remnants were becoming tougher. He covered the remains with debris and lay down. The yearling carcass had been a point of interest for 5 days.
Evidence Indicated a Bear Captured Newborn Lamb
On 30 May 1961 a ewe gave birth to a lamb on a gentle slope at Polychrome Pass. In my notes for that day I wrote that the lamb was on the gentle slope and would be easy prey for a bear or wolf. On my way home I saw a dark bear about half a mile from the mother and lamb. It was climbing a ridge, headed in their general direction. I wondered if the bear would wander in sight of the ewe and lamb, but the country was somewhat broken and the chances seemed good that the bear would not come upon the sheep.
I returned to the sheep in the morning and saw the ewe feeding about 60 yards from the spot where I had last seen her and her lamb. Two hundred yards higher up on the ridge was the bear I had seen the day before. The bear was resting but soon moved over the ridge out of view. The ewe walked steadily to the point where the bear had disappeared and stayed there an hour. Later, she returned to the birth site. The following day the ewe was still in the area, searching for her lamb. Circumstantial evidence indicated that the bear had eaten the lamb.
Unusual Capture of an Older Sheep
On 23 July 1964 a photographer who had been in the sheep hills during the day told me about an unusual incident. The father of the photographer watched from a distance while the boy stalked some sheep for a picture. A bear that earlier had been seen moving up the slope suddenly came upon one of the sheep that the boy was photographing, and pounced on it. The bear had not stalked the sheep but came upon it accidentally. The sheep had 5-inch horns, either a ewe or a young ram.
My observations indicate that a grizzly occasionally captures a weak sheep or a very young lamb. Most captures seem to result from chance encounters, in the same way that sheep carrion occasionally enters the bear's diet. Sheep, even lambs, are not actively sought as caribou calves sometimes are.
Last Updated: 06-Dec-2007