But the canal is one of this animal's most interesting undertakings. It is strictly a freight canal for bringing in food-logs, and is dug out across level ground toward the standing timber.
Canals are commonly three or four hundred feet long, about three feet wide and two feet deep. There was a small but good example at Yancey's in 1897; it was only seventy feet long. The longest I ever saw was in the Adirondacks, N. Y.; it was six hundred and fifty-four feet in length following the curves, two or three feet wide and about two feet deep.
Three other Beaver structures should be noticed. One, the dock or plunge hole, which is a deep place by a sharply raised bank, both made with careful manual labour. Next, the sunning place, generally an ant-hill on which the Beaver lies to enjoy a sun-bath, while the ants pick the creepers out of his fur. Third, the mud-pie. This is a little patty of mud mixed with a squeeze of the castor or body-scent glands. It answers the purpose of a register, letting all who call know that so and so has recently been here.
The chief food of the Beaver, at least its favourite food, is aspen, also called quaking asp or poplar; where there are no poplars there are no Beavers.
THE DAM
Usually the Beavers start a dam on some stream, right opposite a good grove of poplars. When these are all cut down and the bark used for food, the Beaver makes a second dam on the same stream, always with a view to having deep water for safety, close by poplars for food. In this way I found the Beavers at Yancey's in 1897 had constructed thirteen dams in succession. But when I examined the ground again in 1912, the dams were broken, the ponds all dry. Why? The answer is very simple. The Beavers had used up all the food. Instead of the little aspen groves there were now nothing but stumps, and the Beavers had moved elsewhere.
Beaver using his Tail as a Trowel
Similarly in 1897 the largest Beaver pond in the Park was at Obsidian Cliff. I should say the dam there was over four hundred yards long. But now it is broken and the pond is drained. And the reason as before—the Beavers used all the food and moved on. Of course the dam is soon broken when the hardworking ones are not there in their eternal vigilance to keep it tight.
There are many good Beaver ponds near Yancey's now and probably made by the same colonies of Beavers as those I studied there.
Last September I found a fine lots of dams and dammers on the southeast side of Yellowstone Lake where you may go on a camera hunt with certainty of getting Beaver pictures. Yes, in broad daylight.
Let me correct here some popular errors about the Beaver:
It does not use its tail as a trowel.
It does not use big logs in building a dam.
It does not and cannot drive stakes.
It cannot throw a tree in any given way.
It finishes the lodge outside with sticks, not mud.
THE OTTER AND HIS SLIDE
Every one of us that ever was a small boy and rejoiced in belly-bumping down some icy hill, on a sled of glorious red, should have a brotherly sympathy for the Otter.
While in a large sense this beautiful animal belongs to the Weasel family, it has so far progressed that it is one of the merriest, best-natured, unsanguinary creatures that ever caught their prey alive. This may be largely owing to the fact that it has taken entirely to a fish diet; for without any certain knowledge of the reason, we observe that fisherfolk are gentler than hunterfolk, and the Otter among his Weasel kin affords a good illustration of this.
We find the animals going through much the same stages as we do. First, the struggle for food, then for mates, and later, when they have no cause to worry about either, they seek for entertainment. Quite a number of our animals have invented amusements. Usually these are mere games of tag, catch, or tussle, but some have gone farther and have a regular institution, with a set place to meet, and apparatus provided. This is the highest form of all, and one of the best illustrations of it is found in the jovial Otter. Coasting is an established game with this animal; and probably every individual of the species frequents some Otter slide. This is any convenient steep hill or bank, sloping down into deep water, prepared by much use, and worn into a smooth shoot that becomes especially serviceable when snow or ice are there to act as lightning lubricants. And here the Otters will meet, old and young, male and female, without any thought but the joy of fun together, and shoot down one after the other, swiftly, and swifter still, as the hill grows smooth with use, and plump into the water and out again; and chase each other with little animal gasps of glee, each striving to make the shoot more often and more quickly than the others. And all of this charming scene, this group and their merry game, is unquestionably for the simple social joy of being together in an exercise which gives to them the delicious, exhilarating sensation of speeding through space without either violence or effort. In fact, for the very same reason that you and I went coasting when we were boys.
Do not fail to get one of the guides to show you the Otter slides as you travel about the lake. Some of them are good and some are poor. The very best are seen after the snow has come, but still you can see them with your own eyes, and if you are very lucky and very patient you may be rewarded by the sight of these merry creatures indulging in a game which closely parallels so many of our own.
IV
Horns and Hoofs and Legs of Speed
THE BOUNDING BLACKTAIL
When Lewis and Clark reached the Big Sioux River in Dakota, on their famous journey up the Missouri, one hundred and ten years ago, they met, on the very edge and beginning of its range, the Mule Deer, and added the new species to their collection.
It is the characteristic Deer of the rough country from Mexico to British Columbia, and from California to Manitoba; and is one of the kinds most easily observed in the Yellowstone Sanctuary.
Driving from Gardiner, passing under the Great Tower of Eagle Rock on which an Osprey has nested year after year as far back as the records go, and wheeling into the open space in front of the Mammoth Hot Springs Hotel, one is almost sure to come on a family of Deer wandering across the lawn, or posing among the shrubbery, with all the artless grace of the truly wild creature. These are the representatives of several hundred that collect in fall on and about this lawn, but are now scattered for the summer season over the adjoining hills, to come again, no doubt in increased numbers, when the first deep snow shall warn them to seek their winter range.
Like the other animals, these are natives of the region and truly wild, but so educated by long letting alone that it is easy to approach within a few yards.
The camera hunter should not fail to use this opportunity, not only because they are wild and beautiful things, but because he can have the films developed at the hotel over night, and so find out how his camera is behaving in this new light and surroundings.