HEALTH-STATUS OF YOUNG ALASKA STELLER SEA LION PUPS (EUMETOPIAS-JUBATUS) AS INDICATED BY BLOOD-CHEMISTRY AND HEMATOLOGY

Blood chemistry and hematology were examined in 238 Steller sea lion p ups (Eumetopias jubatus) to assess the health status of pups < 1 month of age. Failure of juvenile recruitment (possibly due to nutritionall y or physiologically compromised pups) into breeding populations has b een proposed as a cause of recent declines of this endangered species in Alaska. To identify potential correlations with areas of high popul ation decline, blood chemistry data were considered for three areas: e astern Aleutian Islands (low rates of population decline to stable pop ulations), Gulf of Alaska (high rates of decline), and Southeast Alask a (stable to increasing population). Southeast Alaska pups showed elev ated ketone body concentrations (beta-hydroxybutyrate, (beta-HBA)) and depressed glucose levels when compared with animals from the Aleutian Islands and lower blood urea nitrogen (BUN) and glucose levels than p ups in the Gulf of Alaska. Over 40% of the pups from Southeast Alaska had elevated beta-HBA concentrations suggesting they underwent longer periods of fasting than seen in pups from other areas. Hematocrit (Hct ), hemoglobin concentration (Hb) and water content of the blood exhibi ted typical mammalian relationships. In summary, blood chemistry and h ematology data showed no indication that Steller sea lion pups < 1 mon th old from areas of population decline were nutritionally compromised . (C) 1998 Elsevier Science Inc. All rights reserved.