A New Drug Combination for Cougars

The Kalispell tribe is successfully using a new drug combination for mountain lions and Bart George, wildlife biologist for the Kalispell Tribe Wildlife Program tells the story.

The Project

Bart George and Curt Golden with drugged mountain lionThe Kalispel Tribe Wildlife Program in cooperation with the Washington State Department of Fish and Wildlife Law Enforcement and the Steven’s County Sheriff’s Office is conducting research on cougar behavior and modification through the use of hazing/aversive conditioning.

The program has been developing a new drug combination using BAM and ketamine for cougars (puma concolor) on a project in Northeast Washington State. The project requires cougars to be collared, then tracked/hazed over the course of five weeks, then re-captured and the collars removed. Since the project began in late 2019, we have captured then re-captured 29 individuals, representing 62 actual capture events (three cats were trapped and used as control cats, then recaptured and added to the project).

Captures are performed with trained tracking dogs that trail the cougar and bring it to bay, typically in a tree. Once “treed” the dogs are removed from the immediate location and the cougar is darted using a Dan-inject CO2 rifle, 1.5ml dart, and a 1.5X30 mm collared needle. Darts are delivered to the hind quarter and a catch net is deployed below the tree to help arrest a fall.

The Problems with BAM in Cougars

We have experimented with dosages over the course of the project and initially used 1.5ml BAM per 100lbs (~45kg) body weight. We noticed long induction times (~12 minutes) and lighter anesthesia with the straight BAM.  The cats were also more easily aroused from visual stimulation before being covered or if the headcover slipped off. Other wildlife programs also have noticed longer induction periods, light anesthesia, and sudden arousals. These qualities compromise the animal, make it harder to process and radio-collar, and present a risk to human safety.

A New Drug Combination

Drugged mountain lion with head coverAt the suggestion of our veterinarian, we lowered our BAM dose to 1ml per 100lbs body weight and added 0.3ml of uncompounded ketamine (100mg/ml). This new drug combination has resulted in shortened induction times (~5-8 minutes) and deeper anesthesia occurring around 15 minutes. Small volume injections also allow for most cats to be darted with lighter weight 1.5 ml darts, reducing the energy and potential for injury from delivery. The added ketamine has decreased the cougars’ likelihood of falling by increasing muscle rigidity and helping the cat ‘hang’ in the tree. This dosage provides approximately 45-50 minutes of work time to process the animal.

We wait approximately 50 minutes for the ketamine to fully metabolize before administering the antagonist for the BAM. The dosage for the antagonizing drugs are 2ml atipamezole per 1ml BAM, and a standard 0.5 ml naltrexone for any dosage reversal. This injection is administered intramuscular in the hindquarter that did not receive the dart injection.

Another significant advantage to the BAM/ket combination for cougars is the smooth reversal and recovery. Average time from antagonist injection to “head up” is 4:15, and once the head is up the cougar is on its feet and typically jogging away. There is no prolonged recovery period in which the cougar could be at danger of falling, drowning etc.

About the Author

Bart George Kalispell Tribe biologist with mountain lionBart George is a wildlife biologist for the Kalispel Tribe of Indians, headquartered in Northeast Washington. He keeps hounds for cougar capture and has 15 years of experience pursuing/handling big cats in the Inland Northwest.

Learn more about wildlife immobilizing drug combinations and cougar capture and handling in the online course, “The Foundations of Wildlife Chemical Capture”.