Perrin's beaked whale
Perrin's beaked whale, as with most beaked whales, is virtually unknown. It was described from several stranded individuals that were initially identified as Hector's beaked whales but subsequent genetic tests showed them to be a separate species in 2005. The only existing information on this species has been gleaned from five strandings and two possible sightings at sea.
The Perrin's beaked whale has a small, thick body with a deep tailstock. It has a small head, the melon forming a small bulge, with a short rostrum. The dorsal fin is small and triangular, set about 2/3 of the way back the body. The adult male has a single pair of large triangular teeth at the tip of the lower jaw which extend slightly above the upper jaw. It is dark grey dorsally fading to white ventrally. Only adult males would be readily identified at sea due to their external appearance.
With just two unconfirmed sightings of Perrin's beaked whales, very little information exists on their behaviour in the wild. It is presumed their behaviour is similar to other beaked whales, and scarring suggests competition among males for mates. There is evidence that this species prefers deeper waters (i.e. >1000m) and examination of stomach contents of stranded individuals indicates a diet of mainly squid.
All recorded strandings have occurred around southern and central California, suggesting that the Perrin's beaked whale is endemic to this area of the Pacific Ocean. It is probable that this species suffers from similar threats to the other beaked whales, including noise pollution, bycatch, marine debris, and climate change. The worldwide population is unknown, and it is listed as Data Deficient by the IUCN.