No, not a Navy Seal but a 100kg (~220lbs) fur seal tried to have sex with a 15kg (~33lbs) king penguin. Absolutely bizarre. For 45 minutes, the seal "alternated between resting on the penguin, and thrusting its pelvis, trying to insert itself, unsuccessfully." Apparently, it seems the seal was young and inexperienced. There is a possibility it had been rejected elsewhere ... so the only option it had was ... a penguin!