Heretofore, mention has been made only of the nests of birds built with much labor and usually constructed in trees or bushes. A very large number of species, however, lay their eggs on the ground with little or no attempt to gather around or beneath them any special nesting material. The Killdeer’s eggs are simply deposited in a slight hole scratched in the earth, usually in an open field or on a rocky hillside. The only lining is a few grass blades or smooth pebbles. To protect them from enemies the birds depend much upon the peculiar marking of the eggs, which makes them look like the ground on which they lie, and this seems to be a sufficient safeguard for the eggs and offspring of the species. The Nighthawk lays her two eggs on the bare ground in a field or open woods; and the Whippoor-will’s nest is on the fallen leaves of a thicket at any spot which the bird happens to select.
The Gulls so common along our coast and about the larger lakes make substantial nests, as a rule but not always. I have found them on the islands along the coast of Maine containing not a dozen blades of grass, a seemingly scant protection against the danger of rolling away to destruction.
On the sandy islands of the Atlantic Coast, from Long Island southward, many species of Terns make nests by simply burrowing a slight depression in the sand among the sea-shells. Some of the sea birds of the far North, as, for example, the Murres and Auks, often lay their eggs on the shelving cliffs exposed to the sweep of the ocean gales. These are shaped as if designed by nature to prevent them rolling off the rocks. They are very large at one end and toward the other taper sharply. When the wind blows they simply swing around in circles.
Although we sometimes speak of the bird’s nest as its home, such really is not the case, for the nest of the wild bird is simply the cradle for the young. When the little ones have flown it is seldom that either they or their parents ever return to its shelter.