In the following April after the ice in the pond had broken up, the beavers came out of their winter home and brought with them six young beaver puppies. The father beaver with the white head now went away on his summer exploration trip. We later learned that it was the habit of all male beavers to wander far from home during the summer months. The mother remained at the pond and took care of her six young ones; but with them she moved into the burrow in the bank where we had first seen the old male beaver go to hide.
Many times during the summer we saw the young beavers sunning themselves on the bank or playing in the water near the shore. The mother was always somewhere near, and invariably sounded a warning by pounding the water with her broad tail, whereupon the youngsters would scamper for cover and each would precede his dive by slapping the water with his little ladle-like tail, in feeble imitation of the mother.
One day in June a hawk swooped down, grabbed one of the young beavers and carried him away. Later, a pekan, sometimes called a fisher, killed another one. Apparently the mother scared him off. We found the dead baby beaver, and tracks in the mud gave us the name of his murderer.
Early in July of that summer, while on a fishing trip to Wolf Pond, six miles to the east, Bige and I met our white-headed beaver friend. A slap on the water and a shower of spray informed us that we were recognized. It also spoiled our fishing for at least half an hour.
Toward the end of the same month we met him at the mouth of West Bay Brook on Cedar Lake. This was nine miles west of his home and fully fifteen miles from Wolf Pond, where we last saw him.
In the third week in August we again saw our beaver with a white cap. This time on Pine Brook where he was assisting two other beavers (possibly a brother and sister of his,) in building a dam across the brook. We were fortunate in being able to conceal ourselves, and for a time watched operations. Apparently, our friend was bossing the job and directing the operations of the other two. It seemed that his ability as an engineer was recognized in beaver world, and he therefore had been called in to supervise a difficult undertaking. Thereafter we called him the Chief Engineer, and he many times proved his right to the title.
In September the Chief Engineer returned to his home at Cherry Pond, and there followed a season of great activity among the beavers. Some of their work we were privileged to see in progress, all of it we saw after completion. The young beavers were now about one third the size of their parents, but they all worked.
First, the entire family visited the outlet of the pond, where the Chief demonstrated to the others that with the rocky stream bed and the accumulated drift-wood, a dam would be unnecessary to maintain water in the pond at its present level. Next the house must be enlarged to make room for a family of six instead of two, as in the previous winter. When completed, the house was elliptical in shape, twenty-two feet across its base in the short diameter and thirty feet in its longer dimension. It was also increased in height to eight feet. The peeled sticks piled up under the ice during the previous winter were now utilized in making additions to the house with other sticks and brush brought from the woods.
The interior of the house was enlarged to more than twice its former size by cutting away and dragging out through the tunnels, surplus materials. In doing this, several pillars were left standing for supports to the enlarged ceiling.
Three additional tunnels were dug, making five channels for entrance and exit. Those terminating in shallow water were continued as ditches to deeper water.
The storage warehouse also was made larger and deeper, not only to provide mortar for enlarging the building, but because more food must be stored for six mouths than was required for two. A very high grade of what is called "instinct" in animals must be required to calculate and determine just how much food to store for a winter's supply for a family of a given size. It has been asserted by those who think they know, that in this matter a beaver never makes a mistake. That he also stores an extra amount of food for an unusually long and severe winter. So far as I have observed, they seem to come through the winter in good physical condition.
A picture, which I have longed to secure on a film, but which, so far, I have only been able to fix on the retina of an eye, represents a young beaver about the size of a kitten, not fully grown, in an upright position, holding in his two hands and against his breast a gob of mud, while he laboriously and clumsily struggles up the steep side of his house, on the roof of which he is about to deposit his burden. In the water, towing a young log or a bushy branch, he is much more at home and more graceful in his movements.
The following spring there came out of our beaver house, the Chief Engineer, his wife, four yearlings and a new family of five babies. The "old man" now went off on his annual exploring trip, but he took with him the four older children, while the mother and the babies remained behind. As usual, the house was deserted during the summer months. We now noted several burrows under the bank at widely separate places along shore. Sometimes the beaver would be seen entering one of these holes and again another.
It is interesting and easy, to study the habits of wild creatures, and to note how uniform are their methods and practices. It is not so easy to determine reasons for their peculiar way of doing things. It is of course permissible to speculate, but one might be expected to furnish proof, when an assertion is made. For example, it has been stated by at least two writers, that beaver desert their homes in summer so that the vermin which infest their huts may die off from starvation during the absence of their fur coated hosts.
My own guess, if I were to hazard one, would be that since a beaver house must generally be placed in an exposed position, its owners find that with the sun beating down on its roof during June, July and August, the poorly ventilated interior becomes too hot for comfort. On the other hand, I have noted that the burrows in which they live in summer, are usually found under some overhanging tree, in a cool spot where the sun never penetrates.
During our wanderings through the woods that summer, Bige and I came upon a family of beavers at Mud Pond. These were doubtless also emigrants from the original Raquette Lake colony. Great improvements were in progress. An abandoned and broken down lumber dam at the outlet, which had not been used for lumber operations for many years, was being rebuilt by the beavers, and the Chief Engineer was on hand assisting and directing operations.
On a subsequent visit, we saw the completed dam which raised the waters of the pond about three feet. An area more than a mile long and a quarter mile wide was now flooded. A swamp at the upper end was entirely covered and afforded water transportation from a large grove of poplar trees, which without the dam could not have been reached. Five years later, on the shores of this pond, the beavers had completely cleared of trees more than ten acres of ground. At this time four beaver houses were observed on the shore and on islands in Mud Pond.
When three years old, the children of the Chief Engineer left the parental homestead, mated with relatives in other colonies and set up house building and house keeping on their own account. Some of them, doubtless, located many miles away, others we know built dams and houses on streams emptying into Cherry Pond.
One summer Bige and I were trout fishing on West Bay Brook. We worked up stream about four miles from its mouth, and encountered seven beaver dams and as many houses. At one of these dams we found the white capped Chief working with some younger beavers. Our guess was, that some of these were his own offspring to whom he was giving instruction in engineering practice.
A year later, on Fishing Brook, twenty miles to the north-east, and fully fifty miles from the original colony on the Raquette tributary, we found several beaver colonies. They also settled on Minnow Brook. On Salmon River, from its mouth to Salmon Pond (which it drains), a distance of six miles, there is now a beaver dam every half mile. At one of these dams, a few years ago, we found the Chief Engineer at work. The dam was placed where the current was swift, and a big rock in mid stream was utilized as a pier, against which the two sections of the dam were braced. Such an adaptation of available means to accomplish a difficult engineering feat is surely something more than merely instinct.