When he needs sticks for his nest, he searches out a tree and breaks off the dead branches by his weight. If the stick be stubborn, he rises far above it and drops like a cannon ball, gripping it in his claws and snapping it short off at the same instant by the force of his blow. Twice I have been guided to where Ismaques and his mate were collecting material by reports like pistol shots ringing through the wood, as the great birds fell upon the dead branches and snapped them off. Once, when he came down too hard, I saw him fall almost to the ground, flapping lustily, before he found his wings and sailed away with his four-foot stick triumphantly.
There is another curious bit of bird lore that I discovered here in the autumn, when, much later than usual, I came back through the lake. Ismaques, when he goes away for the long winter at the South, does not leave his house to the mercy of the winter storms until he has first repaired it. Large fresh sticks are wedged in firmly across the top of the nest; doubtful ones are pulled out and carefully replaced, and the whole structure made shipshape for stormy weather. This careful repair, together with the fact that the nest is always well soaked in oil, which preserves it from the rain, saves a deal of trouble for Ismaques. He builds for life and knows, when he goes away in the fall, that, barring untoward accidents, his house will be waiting for him with the quiet welcome of old associations when he comes back in the spring. Whether this is a habit of all ospreys, or only of the two on Big Squatuk Lake--who were very wise birds in other ways--I am unable to say.
What becomes of the young birds is also, to me, a mystery. The home ties are very strong, and the little ones stay with the parents much longer than most other birds do; but when the spring comes you will see only the old birds at the home nest. The young come back to the same general neighborhood, I think; but where the lake is small they never build nor trespass on the same waters. As with the kingfishers and sheldrakes, each pair of birds seem to have their own pond or portion; but by what old law of the waters they find and stake their claim is yet to be discovered.