Tw. Custer et Wl. Hohman, TRACE-ELEMENTS IN CANVASBACKS (AYTHYA-VALISINERIA) WINTERING IN LOUISIANA, USA, 1987-1988, Environmental pollution, 84(3), 1994, pp. 253-259
We determined trace element concentrations in livers of canvasbacks (A
ythya valisineria) collected at Catahoula Lake and the Mississippi Riv
er Delta, Louisiana during, the winter of 1987-88. Forty percent of ca
nvasbacks wintering at Lake Catahoula had elevated concentrations of l
ead (>6.7 mug g-1 dry weight) in the liver; 33% had concentrations con
sistent with lead intoxication (>26.7 mug g-1). Based on the number of
canvasbacks that winter at Lake Catahoula and the frequency of lead e
xposure there, more than 5% of the continental population of canvasbac
ks may be exposed to lead at Lake Catahoula alone. Lead concentrations
in livers differed among months and were higher in males than females
, but were not different in adults and immatures. Concentrations of se
lenium and mercury in livers of females differed among months but not
by age or location. Cadmium concentrations in livers differed by age,
location and month of collection, but not by sex. Frequencies and conc
entrations of trace elements not commonly associated with adverse effe
cts on avian species (aluminum, arsenic, copper, iron, magnesium, mang
anese, nickel, silver, vanadium and zinc) are presented. Except for th
e elevated concentrations of lead at Catahoula Lake, all trace element
s were at background concentrations.