| lead toxicosis and trace element levels in wild birds and mammals at a firearms training facility. | in may 1999, lead poisoning was diagnosed in a yellow-rumped warbler (dendroica coronata) and a gray squirrel (sciurus carolinensis) found at the federal law enforcement training center (fletc), glynn county, ga, based on detection of 6.2 and 90.0 ppm wet weight (ww) lead in the liver of the warbler and squirrel, respectively. from october 21--26, 1999, 72 wild animals (37 mammals and 35 birds), comprised of 22 different species, were collected from a 24-ha area surrounding the fletc outdoor fir ... | 2001 | 11462145 |
| testosterone and prolactin in two songbirds that differ in paternal care: the blue-headed vireo and the red-eyed vireo. | we investigated the hypothesis that species differences in paternal care in birds may result from differences in concentrations of circulating testosterone (t) and prolactin (prl). concentrations of plasma t and prl were compared in breeding blue-headed vireos (vireo solitarius) and red-eyed vireos (vireo olivaceus), passerine congeners with biparental and maternal incubation, respectively. in male blue-headed vireos, plasma t remained low from prenesting to fledgling stages; whereas in male red ... | 2003 | 14644638 |
| exogenous testosterone inhibits several forms of male parental behavior and stimulates song in a monogamous songbird: the blue-headed vireo (vireo solitarius). | natural variation in circulating testosterone is thought to play a role in creating inter- and intraspecific variation in paternal care in birds. experimental elevation of plasma testosterone in males has reduced rates of male care in many species. however, a small number of studies suggest that male care is not inhibited by testosterone when there appears to be strong selection for male care. both genetic monogamy and male incubation are thought to be the result of selection for biparental care ... | 2004 | 15555511 |