Since 2005, bottlenose dolphins have killed at least 44 porpoises off the California coast. For the first time a research team documents details of three attacks and the necropsy of a victim. Almost all the dolphins involved were males.Big surprise there!
Fatal competition between the species seems unlikely, because their diets don’t overlap much, California researchers report in an upcoming Marine Mammal Science. Rough dolphin play or fighting practice still might be a factor, although attacks suspiciously tend to occur at the peak of the breeding season.See? Mating season, a little roughhousing, and the next thing you know, raging porpicide.
Of course humans mate year round.