NATIONAL PARK SERVICE The Grizzlies of Mount McKinley

Grizzly—Golden Eagle Relationships

Any bear on the landscape is worthy of at least a brief inspection by an eagle or other animal interested in carrion, for the bear may be at a carcass. I have watched eagles perched on a slope near a bear at a carcass, patiently waiting and hoping for a chance to eat. And I have often watched an eagle circling over a bear, alighting nearby or diving low over him, with no apparent purpose except idle curiosity or casual play. Like a typical neighbor, he is interested in what the neighbors are up to.

On 9 July 1948 I stopped on Sable Pass and, while scanning the country looking for migrating caribou, saw an eagle perched on the point of a yellow bluff. One hundred yards away a bear was making a considerable excavation in his efforts to capture a ground squirrel. After another 10 minutes of digging, the ground squirrel emerged from one of the excavated burrows and was captured after the bear had made four or five jumps after it. As soon as the squirrel was captured, the eagle sailed low over the bear and alit 100 yards up the slope. After eating the squirrel, the bear rambled toward the eagle who took flight with the aid of a few hops when the approaching bear was only about 10 yards away.

The bear walked south until he came to another set of ground squirrel holes. The eagle alit on the slope not far off, the bear dug out a squirrel, and the eagle flew low over him and alit on the slope beyond. Again the bear walked toward the eagle, flushed it, then moved on and excavated a third ground squirrel while the eagle watched from a nearby hummock. The eagle continued following the activities of the bear in this manner and watched him capture six squirrels in six excavations. After this rather phenomenal success at squirrel hunting, the bear turned to grazing on grass and herbs in a green hollow. The eagle had been accompanying the bear for 1-1/2 hours while I watched. He made no attempt to capture any of the squirrels. Why did he stay with the bear? One could imagine that the eagle was comparing the bear's laborious technique in capturing ground squirrels with his own effortless method of gliding low over the country, appearing suddenly over one sharp ridge after another, and sooner or later surprising a squirrel too far from a burrow to escape. (In McKinley National Park the chief food of the eagle is ground squirrel.) (Fig. 59).

Fig. 59. Both golden eagles and grizzlies hunt ground squirrels and are attracted to carrion. There is enough for both.

On 5 September 1964 I watched a grizzly on Sable Pass digging out a ground squirrel. He was so concerned over the possibility of the squirrel escaping from one of the other exits that he was afraid to dig. He would put his paws in position to pull loose a chunk of sod, then look around to see if the squirrel were escaping, return to digging, but before proceeding, look around a second and even a third time. Three eagles hovered on set wings in a strong wind high over the bear. Later, one of the eagles perched about 25 yards from the bear and another alit about 200 yards up the slope. The third eagle was alternately swooping low over the bear and hovering a short distance above him. After 20 minutes, the bear caught the squirrel deep in the hole and ate it daintily in five or six pieces. The hovering eagle, if he swooped at the right moment, might have captured an escaping ground squirrel, but such an opportunity would be rare because a squirrel trying to escape from a set of holes is usually captured quickly by the bear. However, a photographer in the park reported seeing an eagle capture an escaping ground squirrel after perching near a bear digging for it.

The Golden Eagle and the grizzly hunt ground squirrels and both are attracted to carrion. There is enough for both. Esthetically, their activities add much to the spirit of this wilderness.

Grizzly—Magpie Relationships

Magpies and grizzlies often meet at carrion, a banquet table attractive to all sorts of characters. There is no conflict between these two; the bear takes his share and the magpie is pleased to salvage crumbs that the grizzly considers insignificant.

Occasionally, a magpie is on the scene when a bear excavates a ground squirrel. He sits or hops about while the bear feeds delicately on the squirrel, a small piece at a time. When the bear leaves, the magpie investigates, hopeful that a taste is left. The bear, as he leaves, may see the magpie approach the feeding spot and hurry back to be sure nothing was missed. The always optimistic magpie considers the bear worthy of at least a casual check as he patrols his foraging domain. Sometimes the magpie seems to tease bears for casual amusement. One day, two magpies alit over and over again near two spring cubs, close enough so that a cub twice chased one of the birds. On another occasion I saw a grizzly chase a magpie that had landed where the bear had been resting a few minutes earlier.

In farming country we find birds, such as blackbirds and gulls, following the plow to feed on larvae, worms, and insects that have been exposed. This activity has its counterpart in the wilderness. In McKinley National Park I often have observed magpies keeping bears company while they dug roots and examining minutely the freshly turned sod. One day in September, for instance, a mother bear and her two yearlings did considerable digging on a long slope, each bear off by itself, creating scattered black patches of overturned sod here and there. They were attended by four magpies who were searching the turned-over sod, apparently for insect life. Two hours after the bears had left, the magpies were still foraging industriously in the diggings with such silent concentration that one would think they had just made the discovery. The relationship between these two species chiefly benefits the magpies, but I like to imagine that the birds add a little interest to a bear's life.

Grizzly—Raven Relationships

Occasionally a raven has been seen attending a bear digging roots. As the raven forages in the freshly turned sod, he may be feeding only a few feet away from the bear. Ravens occasionally join bears at carrion, as do the Short-billed Gulls.

Like magpies, ravens are a diversion for bears, may be chased half heartedly at carrion, but usually are ignored.

Grizzly—Insect Relationships

In the high country, bears do not seem to be affected by insects. However, on 15 July 1947, in the woods along the Toklat River where I was watching for wolves, a grizzly's rest was disturbed considerably. I discovered the bear lying in a caribou trail about 40 yards from me. It was a big male that had been climbing a slope and flopped in the trail the moment the lie-down notion struck him. He lay sprawled on his stomach. At intervals he raised his head a few inches and shook it. The mosquitoes were abundant and apparently were bothering him. After a time he became restless, moved down the slope out of my view, and reappeared in some tall willow brush on the edge of the bar. After scratching on a dead snag, he moved across the bar, taking each channel at a gallop, with much splashing and spray. Perhaps other instances when bears seek water are related to pesky insects, but this is usually not evident.