TRACE-ELEMENT CONCENTRATIONS IN 2 SUBPOPULATIONS OF LESSER SNOW GEESEFROM WRANGEL ISLAND, RUSSIA

Lesser snow geese (Anser c. caerulescens) from the Wrangel Island, Rus sia breeding colony spend the winter in two widely separated areas: th e northern subpopulation in southern British Columbia and northern Was hington and the southern subpopulation in the Central Valley of Califo rnia. We examined 19 trace elements in the eggs and livers of geese fr om these two subpopulations to examine whether geese from the differen t wintering areas have similar trace element I,burdens. Eggs collected at the breeding colony from geese of the southern subpopulation had s lightly higher levels of manganese, an element that can cause neurolog ical damage and behavioral changes in chicks, than geese of the northe rn subpopulation. Livers from adult geese collected on the two winteri ng areas showed significant differences in trace elements including co pper, iron, magnesium, molybdenum, and tint. Copper concentrations in the livers of geese from the southern subpopulation were much higher t han those from the northern subpopulation ((x) over bar=116 vs. 46 ppm ; dry weight). Elevated levels of copper may induce anemia in birds. T he differences in trace element concentrations of these two subpopulat ions may be related to farming practices in their wintering areas. Gee se from the northern subpopulation feed in pastures and coastal marshe s and migrate along the coast, but geese from the southern subpopulati on feed predominantly in rice fields and migrate over farm land. Coppe r and manganese are major components of fertilizers and fungicides com monly applied during rice cultivation.