Hybrid whales are uncommon in the wild, but they do exist. These offspring are some of the most rare cetaceans in the world given the unusual nature of cross-breeding species. Two whales species that have been known to breed with each other are the blue whale and fin whale. Norwegians called these animals “Bastards” To give you an idea of the rarity of these hybrids, only five individual blue-fin whale hybrids have been documented since the mid-20th century. Each whale was caught and killed, however, one of the hybrids is an individual that has been spotted returning each year to Skjálfandi Bay, Iceland from 2012-2016.
While hybrids of other whales have been rumored, the only other documented hybrids also involve rorquals. In 2010 a hybrid between a common minke whale (Balaenoptera acutorostrata) and Antarctic minke whale (Balaenoptera bonaerensis) was confirmed by genetic tests. In a photograph was taken of an individual that was believed to be a hybrid bowhead whale (Balaena mysticetus) and North Pacific right whale (Eubalaena japonica), but genetic tests were never conducted to confirm.