58 Bird - Lore
or less inaccessible locations. in trees or on clil‘fs, or by frequenting some isolated island not inhabited by predatory animals.
Habit frequently influences the character of the situation in which the nest is placed. Thus it is customary for arboreal birds to nest in trees, and for terrestrial ones to nest on the ground. There are, how- ever, exceptions to this rule. For example, Herons, Spoon- bills and Ibises are terrestrial. in feeding habits at least, but their nests are usually placed in bushes or trees, Here the helpless con, dition of the young at birth requires a wen-formed nest built in a more or less inaccessible situation. Again, the Nighthawk is, in feeding habit, a bird of the air. but the eggs are laid on the ground, the priecocial young apparently not requiring the shelter of a nest. With the Ducks that nest in holes in trees. sometimes forty feet or more from the ground, the reason for departure from the type of site chosen by the larger number of their family is less evident.
It is to be expected that the character of a bird’s haunts should be reflected in its nesting site: and. as a result, we have some most interest— ing variations in site among birds of the same family but of difierent haunts. Hawks, for example, are usually wood- inhabiting, and the ideal Hawk's-nest is placed in a tree; but the Marsh Hawk builds its nest on the ground, in its marshy haunts. So the Burrowing Owl. of the prairies. nests in holes in the ground; while the wood-haunting members of its family usually select holes in trees. Consequently it follows that, when there is marked variation in the char» acter of a bird's haunts, there is apt to he a correspond-
Inflaerm' 0f Habit
I iifluente 0/ Haunt
Variation . . . . . , . . ing variation in the nature of its nesting Site. The Red— 111 Haunt . . . . . .
l S.’ Winged Blackbirds livmg in reedy marshes weave their nests d”( I t’
to the reed-stems, while those birds of the adjoining alder swamps place their nests in alder bushes. Mourning Doves nest in trees in the east, on the ground in the treeless parts of the west. To one who has been accustomed to see Night Herons‘ nests in swamp maples, sometimes seventy feet from the ground. it is not a little surprising to find the same species building a nest at water»level among the reeds. as it does on the great ‘quill~reed‘ marshes of the west.
While many species show little or no variation in the character of their nesting sites, others place their nests in many and widely different situations even under the same conditions, Robins, for example, aside from nesting in trees at varying heights, place their nests on window-sills. in arbors, summer-houses, or barns, on fence»rails. etc: and in cases of this kind it is of importance to learn whether these birds which depart from the prevailing type succeed in rearing their young.
On Gardiner‘s Island, I}. 1.. where there are no predatory animals.
I’m-iaiionr in Sin
