| heavy metals and selenium in grebe eggs from agassiz national wildlife refuge in northern minnesota. | metal levels in eggs can often be used as an indicator of exposure and of potential effects. in previous work at agassiz national wildlife refuge, northwestern minnesota, the levels of several heavy metals were shown to be significantly higher in the eggs of eared grebes (podiceps nigricollis) compared to those in the eggs of franklin's gulls (larus pipixcan), black-crowned night-herons (nycticorax nycticorax) and double-crested cormorants (phalacrocorax auritus, except for mercury). in the pres ... | 2005 | 16418918 |
| selenium and metal concentrations in waterbird eggs and chicks at agassiz national wildlife refuge, minnesota. | exceptionally high cadmium (cd) and chromium (cr) concentrations were reported in eggs, feathers, or livers of selected waterbird species nesting at agassiz national wildlife refuge (agassiz) in 1994. ten- to 15-day-old franklin's gull (larus pipixcan), black-crowned night-heron (nycticorax nycticorax), and eared grebe (podiceps nigricollis) chicks were collected in 1998, 1999, and 2001 at agassiz and analyzed for selenium (se) and metals including cd and cr. freshly laid eggs were collected in ... | 2007 | 17464443 |
| element patterns in feathers of nestling black-crowned night-herons, nycticorax nycticorax l., from four colonies in delaware, maryland, and minnesota. | the pattern of elements in nestling black-crowned night-heron feathers from a rural minnesota colony differed from colonies in industrialized regions of maryland and delaware. except for chromium, however, the differences did not reflect the elements associated with waters and sediments of the maryland and delaware colonies. therefore, elements in water and sediment do not necessarily bioaccumulate in night-heron feathers in relation to potential exposure. although trace element patterns in feat ... | 2008 | 18496631 |