At left you can see some of the equipment used to administer the immobilization drugs for handling a cougar for collaring. We are using a combination of ketamine (2mg/kg) and medetomidine (0.075mg/kg) with an antogonist of atipamezole (0.3mg/kg) as recommended by "Handbook of Wildlife Chemical Immobilization International Edition". The drugs are delivered via a pneumatic dart that causes minimal trauma to tissue during injection. The dart contains two chambers, front and back. The front chamber contains the chemicals for immobilization, while the back chamber contains pressurized air. As the dart needle is inserted into a large muscle (usually the back of the thigh) a silicon sleeve is pushed aft on the needle, allowing the pressurized air to inject the ketamine/medetomidine combination into the tissue. The dart on the far left is a practice dart for perfecting your marksmanship.