Immobilization of polar bears (Ursus maritimus, Phipps) with ketamine hydrochloride and xylazine hydrochloride.

Free ranging polar bears (Ursus maritimus) were immobilized using a concentrated solution of 200 mg ketamine HCl and 200 mg xylazine HCl per ml. A mean dosage of 6.8 mg (n = 21) of each drug/kg body weight was successful in immobilizing polar bears older than one year and 2.8 mg (n = 6) of each drug/kg body weight was effective for cubs of the year (COY). Mean induction time for bears other than COY was 13.2 min. Mean induction time for COY was 2 min. Bears were tractable for a minimum of 30 min. Male and female polar bears responded similarly to the drugs. Immobilization was characterized by slow deep breathing, relaxed muscles, no excess salivation and no convulsions. The combination of ketamine HCl and xylazine HCl appears to be a useful alternative to drugs previously used for immobilizing polar bears,