Some Blood Values of Wild Polar Bears

Abstract

Twenty-one adult and 12 immature polar bears (Ursus maritimus), captured between September and December 1975, were examined as to baseline values in haemoglobin, haematocrit, erythrocyte number, leucocyte number, mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration, blood urea nitrogen, total protein, cholesterol, bilirubin, sodium, potassium, chloride, magnesium, calcium, phosphorus, glucose, serum glutamic-pyruvic transaminase, serum glutamic-oxalacetic transaminase, alkaline phosphatase, and lactic dehydrogenase. Variations were: higher alkaline phosphatase and calcium levels in cubs than in adults, and an overall increase in blood glucose from October to November. Convulsions in field drugged bears were associated with low levels of conjugated bilirubin. Significantly higher levels of serum glutamic-oxalacetic transaminase and lactic dehydrogenase were found in bears that had been snared rather than captured in culvert traps. There was also a marked increase in leucocyte numbers in the snared bears. J. WILDL. MANAGE. 47(3):520-526 Haematology and blood chemistry of wildlife species can provide information on the physiological state of a population (LeResche et al. 1974, Seal et al. 1975). However, before such data can be interpreted and applied the normal ranges of values are required. Such studies have been undertaken by Halloran and Pearson (1972) on brown bears (Ursus arctos) but there are few published studies of polar bear blood. The haematology of several captive polar bears has been described by Seal et al. (1967) and the serum electrolytes of wild bears have been reported by Manery et al. (1966). This paper describes the physical and chemical blood properties of samples from 33 wild polar bears from the Canadian subarctic. The authors would like to thank the following people for their help and support during this study: R. Best, D. Cross, J. Gallivan, E. Hall, N. Hicks, B. Jahn, H. Pedersen, D. Robertson, I. Stirling, J. Watson and especially M. Hammill who collected most of the blood samples described herein. Blood values were established with the help of Dr. J. H. Lumsden, Department of Pathology, University of Guelph. We are indebted for financial assistance to the World Wildlife Fund (Canada), the Richard Ivey Foundation, the Canadian National Sportsmen's Shows, and the National Research Council of Canada. MATERIALS AND METHODS Blood samples were collected from 21 adult polar bears (8 female, 13 male) and 12 cubs (5 female, 7 male) at Fort Churchill, Manitoba, during October and November, 1975. Bears were captured using culvert traps or foot-snares. Immobilization was accomplished with phencyclidine HCI (Sernylan@, Wyeth Laboratories, Philadelphia) at 0.5 mg/kg. Drugs were delivered in a syringe dart propelled by a Cap-Chur rifle (Palmer Chemical Co.) or a jab stick. Blood was drawn from the femoral vein or artery into three different vials (Vacutainer@, Beckton-Dickinson) containing heparin, EDTA, or no additive (NA). There were no apparent differences between values from the two sources, and consequently results from arterial and venous samples were pooled. Blood in the heparin 1 Present address: Norsk Polarinstitutt, Rolfstangveien 12, Postboks 158, 1330 Oslo, Lufthavn, Nor-