A college professor writes me as follows:--
"Watching this morning a robin attempting to carry off a string, one end of which was caught in a tree, I was much impressed by his utter lack of sense. He could not realize that the string was fast, or that it must be loosened before it could be carried off, and in his efforts to get it all in his bill he wound it about a neighboring limb. If as little sense were displayed in using other material for nests, there would be no robins' nests. It impressed me more than ever with the important part played by instinct."
Who ever saw any of our common birds display any sense or judgment in the handling of strings? Strings are comparatively a new thing with birds; they are not a natural product, and as a matter of course birds blunder in handling them. The oriole uses them the most successfully, often attaching her pensile nest to the branch by their aid. But she uses them in a blind, childish way, winding them round and round the branch, often getting them looped over a twig or hopelessly tangled, and now and then hanging herself with them, as is the case with other birds. I have seen a sparrow, a cedar-bird, and a robin each hung by a string it was using in the building of its nest. Last spring, in Spokane, a boy brought me a desiccated robin, whose feet were held together by a long thread hopelessly snarled. The boy had found it hanging to a tree.
I have seen in a bird magazine a photograph of an oriole's nest that had a string carried around a branch apparently a foot or more away, and then brought back and the end woven into the nest. It was given as a sample of a well-guyed nest, the discoverer no doubt looking upon it as proof of an oriole's forethought in providing against winds and storms. I have seen an oriole's nest with a string carried around a leaf, and another with a long looped string hanging free. All such cases simply show that the bird was not master of her material; she bungled; the trailing string caught over the leaf or branch, and she drew both ends in and fastened them regardless of what had happened. The incident only shows how blindly instinct works.
Twice I have seen cedar-birds, in their quest for nesting-material, trying to carry away the strings that orioles had attached to branches. According to our sentimental "School of Nature Study," the birds should have untied and unsnarled the strings in a human way, but they did not; they simply tugged at them, bringing their weight to bear, and tried to fly away with the loose end.