we do like cowbirds
and cuckoos, which lay their eggs in nests which other birds have built, and cheer no traveller with their chattering and unmusical notes.
This month's cover image,  Plate 99 from Birds of America (printed in stages during 1827-1838) by American ornithologist, naturalist, and painter John James Audubon (1785-1851), shows a pair of oft-vilified brown-headed cowbirds
In North America, this behavior is most frequently observed in Yellow Warblers (Setophaga petechia), which have been recorded building nests with up to six stories in response to parasitism by Brown-headed Cowbirds
(Molothrus ater, Bent 1953, Lowther et al.
are generalist brood parasites, with 101 species victimized, and 44 species documented raising cowbird
young, despite limited and uneven research coverage throughout the species' range (Friedmann, 1929; Carter, 1986; Sealy et al.
A previous suggestion of a brood parasite's benefit, reported nearly 50 years ago from giant cowbirds
parasitizing oropendola nests in Panama, hasn't stood up to later research, says cuckoo researcher Juan Soler of the Arid Zones Experimental Station in Spain.
Pigeons, starlings, sparrows, cowbirds
, grackles and other species find tree filled downtown and urban areas predator free.
With the Alpena Bird Society near bankruptcy as it stumbles into its Centennial year, and its members interested only in gawking at birds, Hospitality Queen Karen decides that the senseless killing of cowbirds
in Joss Canyon, Alpena's last remaining wild land, must stop.
While other studies in the central United States have reported relatively high abundances of brown-headed cowbirds
(Cully and Winter 2000, Powell 2008, Rahmig et al.
There are at least two pairs of cardinals and their offspring among the regulars, along with yellow and purple finches (they turn brown for winter) as well as a rose-breasted grosbeak, red-bellied and downy woodpeckers, cowbirds
, grackles, robins and blue jays.
The birds are shown up-close in flight and interacting with other animals down below: barnacle geese fighting off polar bears that are invading their nests, pelicans plunging into huge shoals of sardine and anchovies and cowbirds
shadowing bison herds to feed on the insects disturbed by their hooves.
Although rates of brood parasitism by brown-headed cowbirds
(Molothrus ater) are high in some warbler species (Ortega, 1998), there are relatively few published accounts with yellow-throated warblers as the host.
Like modern cowbirds
, this species probably fed on seeds and insects large mammals exposed, Oswald said.