Trevor McIntyre faces off against a male southern elephant seal. His job was to distract aggressive males with a broomstick while his colleagues checked on other seals or glued tracking devices to their heads. (Credit: Phathutshedzo M. Radzilani)

(Inside Science) — The first time Paul Krausman jumped out of a helicopter and wrestled a deer to the ground was in 1978. Another researcher had shot a net over the deer moments before, but the animal was not sedated, and it fought hard until Kraus