Elephant Seals Throat Bite

The stakes on this beach are extreme. Northern elephant seals have one of the most lopsided mating systems known in any mammal: fewer than a third of the resident bulls mate at all in a given season, and the dominant harem holders take almost everything. Work at the Año Nuevo colony put the top males' share above 98 percent of matings. A bull who holds his ground through a fight like this one may father dozens of pups, while the animal he drives off fathers none.

Even so, most contests never come to this. Researchers playing recorded calls back to bulls found that the animals memorize each other's individual voices, recognizing the rhythm and timbre of a particular rival's clap-like threat, and an animal who has already lost to a specific neighbor usually withdraws at the sound of him. The blood in the San Simeon shallows is real, but two-ton collisions like this one happen when the ranking between two bulls is still unsettled.