Yellow-rumped Warbler - Behavior

Behavior

These birds one of North America's most abundant neotropical migrants. They are primarily insectivorous. The species is perhaps the most versatile foragers of all warblers. Beyond gleaning from leaves like other New World warblers, they often flit, flycatcher-like, out from their perches in short loops, to catch flying insects. Other places Yellow-rumped Warblers have been spotted foraging include picking at insects on washed-up seaweed at the beach, skimming insects from the surface of rivers and the ocean, picking them out of spiderwebs, and grabbing them off piles of manure. Common foods include caterpillars and other larvae, leaf beetles, bark beetles, weevils, ants, scale insects, aphids, grasshoppers, caddisflies, craneflies, and gnats, as well as spiders. They also eat spruce budworm, a serious forest pest, during outbreaks.

When bugs are scarce, the Myrtle Warbler also enjoys eating fruit, and the wax-myrtle berries which gave it its name. It is the only warbler able to digest such waxy material. The ability to use these fruits allows it to winter farther north than other warblers, sometimes as far north as Newfoundland. Other commonly eaten fruits include juniper berries, poison ivy, poison oak, greenbrier, grapes, Virginia creeper and dogwood. They eat wild seeds such as from beach grasses and goldenrod, and they may come to feeders, where they'll take sunflower seeds, raisins, peanut butter, and suet. On their wintering grounds in Mexico they've been seen sipping the sweet honeydew liquid excreted by aphids. Male Yellow-rumped Warblers typically tend to forage higher in the trees than females do. While foraging with other warbler species, they sometimes aggressively displace other species, including Pine Warblers and Blackburnian Warblers.

They nest in coniferous and mixed woodlands, and lay 4–5 eggs. Females build the nest, sometimes using material the male carries to her. The nest is a cup of twigs, pine needles, grasses, and rootlets. She may also use moose, horse, and deer hair, moss, and lichens. She lines this cup with fine hair and feathers, sometimes woven into the nest in such a way that they curl up and over the eggs. The nest takes about 10 days to build. Nests are located on the horizontal branch of a conifer, anywhere from 1.2 to 15 m (3.9 to 49 ft) high. Tree species include hemlock, spruce, white cedar, pine, Douglas-fir, and larch or tamarack. They may build their nests far out on a main branch or tuck it close to the trunk in a secure fork of two or more branches. Occasionally nest are built in a deciduous tree such as a maple, oak or birch. The eggs are incubated for 12 to 13 days. Nestlings are helpless and naked at hatching but grow quickly. The young are brooded for 10 to 14 days, at which point they can fledge.

The Yellow-rumped has a trill-like song of 4–7 syllables (tyew-tyew-tyew-tyew,tew-tew-tew) and an occasional check or chip call note.

Read more about this topic:  Yellow-rumped Warbler

Famous quotes containing the word behavior:

    The modern world needs people with a complex identity who are intellectually autonomous and prepared to cope with uncertainty; who are able to tolerate ambiguity and not be driven by fear into a rigid, single-solution approach to problems, who are rational, foresightful and who look for facts; who can draw inferences and can control their behavior in the light of foreseen consequences, who are altruistic and enjoy doing for others, and who understand social forces and trends.
    Robert Havighurst (20th century)

    The ease with which problems are understood and solved on paper, in books and magazine articles, is never matched by the reality of the mother’s experience. . . . Her child’s behavior often does not follow the storybook version. Her own feelings don’t match the way she has been told she ought to feel. . . . There is something wrong with either her child or her, she thinks. Either way, she accepts the blame and guilt.
    Elaine Heffner (20th century)

    One cannot demand of a scholar that he show himself a scholar everywhere in society, but the whole tenor of his behavior must none the less betray the thinker, he must always be instructive, his way of judging a thing must even in the smallest matters be such that people can see what it will amount to when, quietly and self-collected, he puts this power to scholarly use.
    —G.C. (Georg Christoph)