NATIONAL PARK SERVICE Fauna of the National Parks of the United States No. 4 Ecology of the Coyote in the Yellowstone

ON NOVEMBER 13, 1937, on upper Oxbow Creek, a number of soaring ravens attracted my attention to a dead cow elk lying on an open slope. From a prominence I could see some coyotes as well as several magpies, at the carcass. Lying contentedly on a knoll 150 yards away was a coyote which had apparently had its fill, for it was relaxed on its side and showed no interest in its surroundings. One coyote was at the elk and chased away another which approached to feed. Soon a fourth came to the place on the run. As it approached it put its head down and arched its back. The coyote at the carcass fled; it seemed to recognize the newcomer as its superior. Two coyotes trotted over a rise out of sight.

Although it was a dull, grey day I moved up nearer in order to try for some pictures. As I was approaching the carrion a coyote appeared on the skyline about one-third of a mile behind me. It trotted briskly toward the carcass, passing about 60 yards to one side of where I was crouched. I circled the dead elk and came up to within 75 yards of it, shielded from the coyotes by a few fir trees. There were now five coyotes, standing shoulder to shoulder, tugging at the meat. The ravens had seen me from afar and had left, but eight or nine magpies were there. Magpies on the carcass were sometimes thrown off balance by the tugging of the coyotes. One by one, four of the coyotes left the carrion and trotted away. Each of the four, upon leaving the carcass, vigorously rubbed its throat and muzzle, and sometimes its chest, on the grass to clean the fur. In this way, the blood and dirt were thoroughly wiped off. The fifth coyote remained several minutes after the others had left. When finishing, it also wiped its muzzle and then howled half-heartedly.

When all the coyotes had gone, I hunched up against a niche in some bare rocks 50 yards from the carcass. There was no cover near at hand. In a few minutes a coyote came over the slope behind, and, upon sighting me from a distance of 15 yards, galloped out in the flat. It made a large half circle around the carcass, moved back to a knoll 100 yards away, and lay down. The magpies in the meantime were busy gorging themselves and carrying away quantities of scraps to cache in the scattered neighboring groves.

In a few minutes another coyote appeared and approached the carcass, weaving back and forth several times before coming to it. This coyote seemed hungry, feeding rapidly and jerking at the carcass vigorously. The magpies were perched all about it, only 2 or 3 feet away. Once the coyote made a dash at the magpies, apparently to chase them away. Sometimes it received a start when a magpie alighted only a couple of feet from its head. It was finally attracted by the noise of my camera shutter and trotted up to within 10 yards of me before it recognized what I was and galloped away.

I walked nearer the carcass to photograph the magpies and crouched about 20 yards from it to wait for the magpies to reassemble. I had barely taken a position when another coyote came into the area and trotted directly to the carrion without noticing me. However, it apparently got my scent for it dashed away. I had been at the carcass for 3 hours and estimated that during this time it had been visited by 10 different coyotes.

On November 13, 1938, at 8 a. m., I found a dead bull elk in the sage about 75 yards from the road near Blacktail Creek. I later learned that the elk had been killed by a truck on the evening of November 11. At the carcass were 5 coyotes, 12 ravens, and 10 magpies. At 4 p. m. there were 6 coyotes, who, with one exception, left shortly after. This one tugged at the flesh in the usual manner, sometimes bracing all four legs, but more often only the front legs. It occurred to me that the hyena, which feeds chiefly on carrion, may have developed its fore legs and shoulders at the expense of the hind quarters by a feeding habit at carrion in which it used mainly the front legs.

On the morning of November 14, there were 3 coyotes at the dead elk, 3 others within 50 yards of it, and 6 more scattered out over the sagebrush either going or coming. No doubt the presence of a carcass becomes widely known, causing more and more coyotes to assemble. One of the three at the carcass seemed especially pugnacious, at intervals driving off the other two animals, and dashing after the magpies, of which there were a dozen hopping and flitting over the body. After being driven away several times one of the coyotes moved off, but the other was finally tolerated and wedged itself between the hip bones in its efforts to get at some uncleaned portion of the skeleton, which was fast becoming bare of flesh. Later another coyote approached in the characteristic challenging attitude with back arched and jaws wide open. It galloped and trotted in this attitude for about one-quarter of a mile. Without hesitation it attacked the first coyote it encountered, which was the pugnacious one. There was a momentary sparring with jaws as both humped up, but the newcomer bumped his shoulder against the other and forced it to retreat, then dashed after some magpies, and, after strutting once around the elk remains, began to feed. Soon a light-colored coyote boldly approached and attacked. There was resistance, but after some snarling and scuffling the one at the carcass moved off a few feet. His back remained arched and he returned to feed undisturbed. The third coyote was still feeding between the hip bones. Some ribs and leg bones had been carried off 50 or 60 yards to a spot where several minor quarrels and some bluffing took place, similar to that occurring at the carcass. Ravens sat in the snow at varying distances from the carrion, which they had left on my approach. Once a raven tried to fly off with a rib in its bill. Three or four times a coyote approached a raven that was feeding and, when the raven flew, examined the spot where it had been.

Four coyotes ran off together across the sage and over the ice of a small pond. The large one in the lead was attacked several times by the one behind it so that it had to stop and face about to protect itself. This nipping seemed to be done in play.

Some of the coyotes rested in the sagebrush between 50 and 400 yards from the carrion. Once eight coyotes trotted off, three of them bunched in the lead, the others straggling behind at various intervals. Some of them spent a little time hunting mice. During the morning there were several brief fights, one in which a coyote rolled over on its back and was bitten somewhat around the throat.

In the afternoon I approached within 35 yards of three coyotes at the carcass in order to take pictures. They were so occupied that I was able to move gradually into full view and take a number of pictures. They paid little attention to the noisy camera shutter. One of the coyotes saw me, but after running off a short distance and seeing the others remaining, it returned and lay down 60 yards away. The coyotes were active through the day, coming and going to the carcass continually.

Where the coyotes are depending mainly on carrion for food and there is not sufficient to go around, it is very probable that there is an elimination of the weak and a survival of the fittest. The weak can only eat after the strong have feasted, and if the strong devour what there is, the weak would of course go hungry and become weaker.

Figure 4— The coyote in the center is trying to bluff the newcomer at the right, but without much success. This challenging attitude is frequently assumed by coyotes while at a carcass.
Blacktail Deer Creek, November 14, 1938.

CACHING

THE coyote often caches surplus food. This may vary in amount from a whole deer quarter to a piece of deer meat an inch or two in diameter such as was found cached one-third of a mile from a carcass on lower Blacktail Deer Creek on November 20, 1937. On February 15, 1937, coyotes were observed hiding large pieces of a deer, and once a coyote was observed moving away from an elk carcass with a leg bone. Often it has been observed that deer have been "cleaned up" in a single night. Although much of a deer may be eaten on the spot, it is likely that a large part has usually been carried away. In northern Minnesota I have frequently found snowshoe hares stored under the snow by coyotes.

COYOTE-RAVEN RELATIONSHIPS

IN WINTER, when a considerable part of the diet both of the raven and the coyote consists of carrion, their similar interests draw these two species together. They are interested in each other's actions; the raven watches the coyote and the coyote watches the raven. If one has found a source of food he is sure to be joined sooner or later by the other. The coyote-raven relationship is an example of a loose symbiosis.

At a carcass, the raven, because of its wider view when in the air or on top of a tree, frequently warns the coyote of approaching danger or other intrusions. The coyote is usually occupied tugging at the carcass while the ravens are scattered about, some at the carcass, others soaring or sitting in nearby trees, so it is difficult for anything to escape their notice. The coyote takes their warning and becomes alert, but it may only look around briefly, and, seeing no danger, continue to feed. Some incidents may serve to show how closely ravens and coyotes observe one another when food is involved.

On May 12, 1937, in Pelican Meadows I watched a coyote hunting on a snowdrift. After a short period of intent watching it pounced. This was followed by a little digging in the snow and some more quick pounces. A raven flying overhead turned its course and lit on the snow 10 yards from the coyote. Here it remained patiently waiting for about 5 minutes while the coyote dug some more. The latter then took a few alert steps, only to return again to the same spot. When the coyote wandered off, the raven walked to where the coyote had been digging and gave the spot a thorough investigation.

On the morning of January 15, 1938, I saw a coyote trotting along the base of Mount Everts. on the margin of a wide flat. Near the opposite side of the flat a raven was standing on a snowdrift. When the coyote had trotted to a point opposite the raven and about 200 yards away it turned its course directly toward the raven on the snowdrift. The bird by that time had been joined by a second one which had alighted to feed on a tiny food morsel it had been carrying. When the coyote was somewhat less than 10 yards from the feeding raven it made a quick dash for the bird. The raven easily escaped and lit again a few yards to one side. The coyote sniffed the spot where the raven had been feeding and then made another dash for it. These tactics were continued for some time. It appeared that the coyote chased the raven in order to pick up some fragment of food that might be left behind because of the sudden departure. The coyote made six or seven dashes at the bird before it flew off about 250 yards. After peering at the departed bird, and seeming to hesitate whether or not to follow, the coyote trotted after it. When the coyote had covered half the distance the raven circled back over the coyote, which looked up at it as it wheeled 15 or 20 feet overhead.

The raven lit on the snow again to feed on its food morsel and the coyote trotted along as if to pass it, but suddenly turned to make another quick charge. These rushes, as before, were repeated five or six times. Once the coyote leaped high in the air toward the raven and rolled over twice when it hit the snow. The raven finally flew away along the river and coyote disappeared in a draw. It appeared that both animals were enjoying the fun, for the raven could easily have flown away to escape if it were annoyed, and it would seem that the coyote, which was probably well fed by the abundant carrion, would not have been so persistent unless he were enjoying the play.

In the winter of 1937—38 on the Federal Elk Refuge in Jackson Hole one of the men reported a coyote playing with a mouse. A raven was attending the coyote and would try to get the little creature when the coyote left it out of reach. Before the raven could get the mouse the coyote would retrieve it. This game continued for some time.

At the Mammoth dump on March 29, 1938, a raven and a magpie were perched a few yards from a coyote which was chewing vigorously on some food. The moment the coyote left, both birds and a second magpie flew at once to the spot and quickly picked up the crumbs. The crumbs left by the coyote were no doubt easier to eat than was most of the garbage. The alertness and watchfulness of the birds indicated that feeding on the small morsels left by them was a common practice.

On February 15, 1938, I witnessed an incident which showed that the ravens could be quite vexatious. A short distance above the mouth of Bear Creek several ravens were circling low and lighting on the ground, across the Yellowstone River from me. Through my binoculars I made out two coyotes tugging at a carcass lying on a bench sloping away from the river. About 15 ravens, the number varying because of continuous arrivals and departures, were near the carcass. Some were in the air, some perched in the nearby trees, and some on the ground by the carrion. Magpies, as usual, were also assembled and hopping about barely out of reach of the coyotes. Frequently during the hour that I watched, the coyotes made rushes at the magpies and ravens, not, it seemed, in any attempt to catch the birds, for they never followed through with their attack, but rather to drive them away. For about 20 minutes the coyotes continued feeding. I was on the bank of the river opposite the carrion and from this point it was just out of my view, and so, at times, were the coyotes feeding on it. One of the coyotes seemed small, with a scraggly light-colored coat. He had a lame left front foot which was used lightly and sometimes not at all. This lame member of the group presently started up the slope carrying the front leg and shoulder bone of a fawn deer with most of the hide attached. When he had gone up the slope about 10 yards a large dark coyote followed with a rush, causing him to drop his burden and retreat for a few yards. The dark animal, with back sharply arched, head held low, and lips drawn back from his teeth, returned to the carcass. The lame one cautiously retrieved the deer quarter and moved up into a small grove of Douglas firs. Six or seven ravens followed him as he went, circling a few feet above. In a few minutes the lame coyote emerged from the grove where he had cached the carrion. He looked back up the hill toward the grove where some ravens were lighting in the trees, apparently having some misgivings about the security of his cache. He then carried a second large piece of the meat into the grove and was followed by the dark coyote which was carrying a quarter with most of the meat removed but with much of the hide still clinging loosely. The dark coyote disappeared in the grove, but later crossed an opening higher up the slope, still carrying what remained of the deer quarter. He dropped his load on the snow and stood looking alternately at his burden and at the circling ravens which had been following closely. He was not so naive about making his cache as was the lame one, who did not seem to realize that potentially all the ravens in the region knew the location of his store. The dark one seemed much dismayed. He probed his nose into the snow, picked up the bones, looked up at the ravens, and walked into another grove. The ravens followed, perching on the trees along his route. The coyote moved a long way up the slope to still another grove where he again stood watching the ravens, seeming completely perplexed. When he moved into the woods I left the scene for I had been watching for more than an hour with the temperature about 30° below zero. As I left I caught a glimpse of a third coyote at the carcass. The caching of the remains shows why carcasses at times so quickly disappear.

Figure 7— Coyote and Raven at Play.
Sketched from Life by O. J. Murie

COYOTE-MAGPIE RELATIONSHIPS

ALONG with the raven, the magpie is closely associated with the coyote during the winter months. In the same manner, the magpies were observed to warn coyotes of danger.

At times it seems that there must exist a compact between magpies and coyotes, for often these birds at a carcass hop about only a few feet from the coyotes. Magpies are very alert and cannot be readily captured by coyotes, who no doubt learn that their efforts along that line are rather futile and after a time stop trying. I have seen a coyote chase magpies away from a carcass, apparently with no effort to harm them. However, occasionally a magpie is eaten, for feathers were once found at a dead buffalo and magpie remains have been found in at least one stomach of a coyote that appeared to have been feeding on carrion.

Figure 5— A magpie (indicated by arrow) is feeding only a couple of feet from the head of a coyote.
Blacktail Deer Creek, November 14, 1938.

Figure 6— Magpies and a coyote feeding on an elk carcass. The flying magpie (indicated by arrow) is returning from a trip to the woods to cache a morsel.
Blacktail Deer Creek, November 14, 1938.

FAMILY HUNTING GROUND

IN 1937 Gibbon Meadows was apparently the hunting ground of a coyote family. These animals were frequently seen hunting in the meadow and had spent much time resting and playing among the small scattered groves of trees along the edge of the meadow. There were many freshly worn trails in the grass, numerous beds, and several places where coyotes had been digging around the roots of trees. Many droppings occurred in the open as well as among the trees. A total of 162 droppings were found in the place on September 3 and 4. The pups had climbed logs and upturned roots of fallen trees in their play. One of the pups was seen on September 4 at the rendezvous. Grasshoppers occurred here in varying amounts up to 100 percent in 95 of the droppings, which suggests that the pups eat more grasshoppers than the adults.

SOCIABILITY

COYOTES move alone or in small groups. If two or three are together, any one of them is likely to go off on a lone excursion. Often several coyotes are assembled at a carcass or in the same meadow hunting mice, but any one of these may have wandered to the area alone and is likely to depart alone. On meeting, two coyotes may trot toward each other, may even touch noses, and, after hunting about near each other, move apart. In winter small groups of coyotes often travel together; as many as six have been seen in a group. Usually these bands seemed to consist of family parties. On March 25, 1938, I watched six coyotes which were resting together and apparently on friendly terms. Two seemed to be adults, but of course identification was not certain. As will be related under coyote-deer relationships, four of these coyotes had passed close to some deer and after stopping near them for a short time had wandered off out of sight. They reappeared on the slope near the top of the ridge at 11:30 A. M. The group, apparently an adult and three pups, after howling together, lay down on the snow, the pups flat on their sides with necks arched far back, the old one occasionally looking casually to either side. After a while all four looked up the slope on which a large coyote and a pup appeared. The latter came down the slope and stopped on a bench about 60 yards above the others. The big one, an adult, took a position on a flat rock and lay on his stomach, his legs stretched forward and paws hanging over the edge of the rock. He seemed to be watching over the four below him sleeping in the bright sunshine. The pup stretched out on its side in the snow a few yards away. The old one with the three pups walked over to one of them and nosed it. The pup lay quiet except that it pushed its nose toward the old one, who then walked up the slope, passing within 3 or 4 feet of the big coyote on the rock. It approached the single pup, which rolled over on its back with both front legs doubled up. The old one smelled of the pup's stomach, then it too stretched out flat on the snow. Presently the animal on the rock faced the old one and the pup, and lay on its side. All six coyotes were now lying flat; none were watching. After 45 minutes had elapsed all but one of the pups trotted away; this one slept 15 minutes longer. It was aroused by some deer a short distance from it, which jumped away when they saw me approaching the coyote in my stalk for a picture. The coyote looked toward me, where I crouched in plain sight on the open snow slope, but did not rise until it heard the click of the camera. Then it jumped up and trotted toward me, veering to one side so that it passed me at a distance of 35 yards. It circled behind me at this distance until it got my scent, then, cautious and not very much alarmed, trotted off in the direction the others had taken.

An observation, related by Almer Nelson, in charge of the Federal Elk Refuge on the outskirts of Jackson, Wyo., illustrates well, it seems to me, the spirit of comradeship in the coyote. At daybreak, in the middle of the winter, Nelson looked out of his window and saw six coyotes scattered over the fields hunting for mice. While he watched, the coyotes in their hunting gradually moved toward a center until they were all assembled. Here they sat in an irregular circle and howled in chorus. The clamor soon came to an end and the coyotes dispersed over the fields, each going on its way, to return again in the evening.

PLAY

COYOTES are playful like dogs. Along the Yellowstone River below Crevice Creek, tracks showed that coyotes were wont to play on an open bench. Several times I passed the area after a fresh snow, and each time it appeared that coyotes had been dashing about on it. In the trails I occasionally saw sticks which the coyotes had been chewing. Once I saw a coyote coming toward me along the trail carrying a sprig of sagebrush. At intervals he tossed the branch into the air and caught it.

SWIMMING

Coyotes were occasionally seen crossing small streams, such as the Lamar and Gardiner Rivers. In midwinter Ranger Gammill saw an undisturbed coyote swim the Yellowstone River above the mouth of Blacktail Deer Creek. Upon emerging from the water a coyote will generally shake itself and frisk around to remove the water from its coat and get warm. Apparently on occasion coyotes do not hesitate to enter water and even cross deep, swift-flowing rivers.

LIMITATIONS ON TRAVEL

IN the North, sled dogs frequently get sore feet, so that it is often necessary to equip them with moccasins. A crust through which dogs break, or coarsely crystallized snow, may wear raw spots on the sides of the toes, so as to cause them great discomfort. If conditions are bad a dog team may be considerably crippled. Some dogs are more subject to injury from unfavorable snow conditions than others, but all are susceptible.

It is probable that the coyote is less subject to sore feet than most domestic dogs, but many signs were observed that coyotes are also subject to this affliction. Two or three coyotes were seen which had a slight, almost imperceptible, limp characteristic of snow-injured feet. On a number of occasions little specks of blood were found in coyote tracks. These were especially prevalent during one period when a light crust, which had formed on the snow, was too weak to bear the weight of the coyote, and the animal broke through the surface from 1-1/2 to 4 inches. At this time the snow had taken a coarse crystalline form which aggravated the effects of the weak crust. Such snow conditions probably handicap the coyote sufficiently to reduce its movements.

TOLERANCE OF HUMANS

COYOTES often become quite tame when protected, just as they become exceedingly wary and wild when hunted. Occasionally an exceedingly tame and friendly coyote is found in a litter of pups. During the winter of 1936—37 a coyote became so tame at Mammoth that it was frequently fed and as a result of close association with it at least one person was bitten. This animal was finally shot because of its undue familiarity—another example of the unfortunate consequences sometimes resulting from feeding and taming wild animals that are large enough to injure a person.

During the winter of 1936—37, when the coyotes were hard pressed for food, two or three frequently came to the ranger's residence at Tower Falls to feed on garbage and to get food morsels tossed to them. One of these coyotes became so tame that it would come to the cabin when the ranger whistled. The following summer a tame coyote, apparently the one which had been fed during the winter, was seen several times at Tower Falls. By throwing pieces of cheese to it we were once able to bring it within 6 or 7 yards of us.

Dr. Frank Oastler told me that he found a coyote in Hayden Valley which was so tame that it would almost feed from his hand. I met a coyote in Hayden Valley the following summer that came trotting up within 15 yards of me. After I had returned to the car for a camera he became more wary.

Sawyer, in Yellowstone Nature Notes (November 1924, p. 3), reports a coyote pup coming up within 40 or 50 yards of him while he was tying a horse at the Canyon barn. The pup apparently returned several times, for Sawyer writes: "A few days later this companionable coyote called at the Canyon Ranger Station, whereupon his intercourse with man came to an end."

Since the cessation of control in the park, coyotes in general have become less wary and are therefore probably more in evidence along the roads. This is a factor that must be taken into consideration in comparing the present size of the coyote population with what it was when control was practiced.