The best habitat model for American Robins
suggested that detections increased with increasing total shrub cover, decreasing numbers of stem classes one and two, and increasing buckthorn fruit abundance (Table 2).
GS = grasshopper sparrow, EM = eastern meadowlark, BO = bobolink, SS = song sparrow, FS = field sparrow, MA = mallard, RO = American robin
, RW = red-winged blackbird, BT = brown thrasher and WF = willow flycatcher (bars = SE).
On average, American Robins
weighed 77 g throughout the year in Pennsylvania and 86 and 84 g for males and females, respectively, during winter in Ithaca, New York (Sallabanks and James 1999).
Although the relative frequency of northern cardinals and American robins
was approximately the same at Tompkins County sites, northern cardinals were 7.
Some twitchers had travelled hundreds of miles to catch a glimpse of the American robin
, which had been roosting at an industrial estate for two months.
Both American Robins
and Cedar Waxwings have been well studied in their breeding range and during their reproductive period (see Hamilton 1943; Knupp et al.
Dawn and dusk singing of male American Robins
in relation to female behavior.
A seasonal shift from American robins
to other avian species was noted with Cx.
A host may use tactile stimuli detected during incubation to identify a foreign egg by size (Rothstein 1982), as suggested for Rufous Horneros (Furnarius rufus) and American Robins
(Rothstein 1982, Mason and Rothstein 1986).
Poor sensitivity occurred in most raptors, Mourning Doves (Zenaida macroura), Fish Crows (Corvus ossifragus), and American Robins
These results agree with those obtained for other species of passerines inhabiting different environments (Wang and Weathers 2009), and with early field observations of Hermit Thrushes (Stanwood 1910) and American Robins
1) reporting the competence of American robins
as reservoir hosts for Lyme disease spirochetes.