In the Philippines the local people gather the juice of the coconut inflorescence in bamboo tubes placed in the crowns of the palms. This juice ferments quickly and provides a refreshing, mildly intoxicating drink. A little parrot of the Philippines, the hanging parakeet, has a taste for this drink, comes and drinks from the containers, sometimes becomes drunk, falls in, and drowns.
The California woodpecker ordinarily differs from many birds because it does not lead a hand-to-mouth existence but stores food. These woodpeckers feed extensively on acorns, and one way they store them is by drilling holes in the bark of a tree and fitting an acorn into each hole. The whole trunk of a tree thus may be pitted with stored acorns. When the acorn crop fails and the nuts are scarce the woodpecker goes through the same storage activities but, being unable to find sufficient acorns, it stores pebbles instead. These pebbles are, of course, quite useless to the woodpecker, and this is an interesting example of an instinct "gone wrong."
Sometimes these woodpeckers have another method of storing their acorns. This is by dropping them into cavities in tree trunks, but when stored in such a way there seems to be no way for the birds to reach them. Here again we have a blind impulse to store acting in such a way that the bird gains nothing by the act.
The raven is ordinarily and quite correctly considered one of the most intelligent of birds, but a raven I kept in captivity and fed small fish attempted to store some of them by pushing them through a knothole in the back of its cage. The fish fell about fifteen inches below the knothole, where the raven could not possibly reach them. After pushing each fish through the raven peered through the knothole though it could not see the fish. Here again we have the instinctive storing act carried out in such a way that it produced no benefit to the bird.
The late George Latimer Bates, noted ornithologist, studying the birds of West Africa, found a most surprising thing in connection with one of the honey-guides. As a group, these birds are noted for the habit of attracting the attention of human beings and leading them to bee trees, presumably so that they will break down the bee tree for the honey, and the birds can feed on the scraps left over. Bates found that the West African species is parasitic on other birds in its nesting habits and its young have been found in the nesting hole of a little barbet. This barbet was a much smaller bird than the honey-guide and the entrance to the nest hole was so small that Bates doubted that the honey-guide would have been able to get in to lay its egg. He suggested that the egg may have been laid elsewhere and deposited in the nest by the parent's bill. It is difficult to understand how the young honey-guide would be able to get out, for when fully fledged it would have been far too large to squeeze through the entrance that admitted the tiny body of its foster parents, the barbets. This is an almost incredible story and if true looks like a case of maladaptation.
FEATHERED BABY SITTERS AND CO-OP NURSERY NESTS [Ref]
Co-operative nurseries, where a few parents look after the young while the rest of the adults, temporarily freed of the care of their offspring, can go about their other affairs, appear in the bird world.
The wild turkey of our Eastern United States commonly steals away singly to lay its eggs and incubate them in its nest on the ground. But occasionally it happens, Audubon writes, that several hen turkeys associate together and lay their eggs in one nest, and raise their young together. With the turkey apparently there is little division of labor, as Audubon writes of finding three hens sitting on forty-two eggs, but he says that one of the hens is always on the watch at the nest so that natural enemies have no chance to rob it.
A GREGARIOUS BIRD What is of only occasional occurrence in one species may be the regular course of events in another, and in the ani we find it customary for a number of birds to nest together. The anis are moderate-sized cuckoos living in the tropical Americas. The smooth-billed ani is perhaps the best known, for Dr. D. E. Davis, when studying at Harvard for his doctor's degree, made a special trip to Cuba to study them in the field. The smooth-billed ani goes in flocks the year round. Usually there are about seven birds in the flock, but there may be as many as twenty-four. The nest is a bulky structure of twigs and fresh leaves. When nest building starts usually one bird is most active, but as many as five birds were seen carrying in sticks at one time. When the nest of sticks and leaves is finished several females may lay their eggs in it. But apparently only one bird incubates at a time, and the male takes his turn at incubating. When the young hatch, after about thirteen days, most of the adults in the colony help feed the young.