[Illustration]
There are occasionally discovered behavior patterns of birds that are
so unusual as to make one stop and wonder. They are unusual for birds
generally, but in a species here and there they are the regular thing.
Such is the placing of a shed snakeskin in their nests by some birds.
A bird like the English sparrow, or the road runner, which uses a
variety of material coarse or fine, would be expected to use shed
snakeskins occasionally, as it came across them. But there are a number
of species that seem to use snakeskins regularly in their nests.
It would seem that the birds deliberately sought out the skins for
this purpose, as though they were as much a part of the nest as the
mud in the bottom of a robin's nest or the fresh green grass heads
ornamenting the entrance to some weaverbirds' nests.
SOME HABITS BAFFLING I have long since given up thinking that every
aspect of a bird's life must serve a useful purpose. Indeed I have
already pointed out some definite maladaptations. But usually every
type of behavior has a logical origin. By considering its occurrence in
various species and against the background of the bird's everyday life
some correlations usually can be found.
The list of birds habitually using snakeskins in their nests is short,
as follows:
1. Great-crested flycatcher--belonging to the New World flycatchers,
breeding in Eastern North America and nesting in holes.
2. Arizona crested flycatcher--a relative of the great-crested variety,
with similar habits.
3. Blue grosbeak--an American member of the sparrow family, making an
open nest in bushes.
4. Black-crested titmouse--a member of the chickadee family, living in
Western North America and nesting in holes.
5. Bank mynah--a starling, living in southern Asia and nesting in holes
in banks.
6. Rifle bird--an Australian bird of paradise, making a cup-shaped nest
in trees.