As with all beaked whales (Ziphiidae) there is very little data on M. bidens. This species was the first of the beaked whales to be described. It was described by John Sowerby in 1804.
A young animal, that was kept in a dolphinarium for a few hours, was recorded using high frequency sound pulses to echolocate.
Communication Channels: acoustic
Perception Channels: visual ; tactile ; acoustic ; echolocation ; chemical
There is very little data on Sowerby's beaked whales. As a result there is little information on population sizes, current or historic, to determine conservation status. This species is rarely seen in the open ocean, most records are from strandings.
US Federal List: no special status
CITES: appendix ii
State of Michigan List: no special status
IUCN Red List of Threatened Species: data deficient
Sowerby's beaked whales are occasionally caught in fishing gear, damaging nets in the process. Arguably this is more traumatic for the whales than fishing crews.
Sowerby's beaked whales were once infrequently harvested by Norwegian whalers. They are no longer hunted actively.
Positive Impacts: food
Little is known about the role of Sowerby's beaked whales in the northern Atlantic ecosystem. They are undoubtedly predators of marine organisms.
The diet of Sowerby's beaked whales consists mostly of squid, octopus, and fish. A necropsy of one individual showed stomach contents that included bottom-dwelling and deep water fish.
Animal Foods: fish; mollusks
Primary Diet: carnivore (Piscivore , Molluscivore )
Sowerby's beaked whales are found in temperate to sub arctic waters in the eastern and western North Atlantic. They are found around the British Isles and are known to occur from Newfoundland to Massachusetts. Sowerby's beaked whales occur as far north as Labrador in the west and in the Norwegian Sea in the east, southern limit is thought to be somewhere between 33ºN and 41ºN.
Biogeographic Regions: nearctic (Native ); palearctic (Native ); atlantic ocean (Native )
Sowerby's beaked whales are found in cool to warm temperate offshore waters of the North Atlantic Ocean. They are usually observed in open water and most often seen in areas were depths range from 198 to 1524 m.
Range depth: 198 to 1524 m.
Habitat Regions: temperate ; saltwater or marine
Aquatic Biomes: pelagic
The is no data on the lifespan in M. bidens.
Mesoplodon bidens is bluish grey to slate grey in color, with a lighter underside, grey and white spots may be present on the body with limited scaring. Mesoplodon bidens have a long slender beak that contains a pair of teeth midway up the lower jaw. They have a long think body, long flippers for the Mesoplodon family, and no notch in the fluke. The dorsal fin is quite small with a rounded tip and may appear falcate. Young M. bidens have a light blusih grey to white underside, more prominant than in adults.
Range mass: 1000 to 1300 kg.
Range length: 5 to 5.5 m.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
There is no information about predation on Sowerby's beaked whales. Once they reach their adult size it is likely that they are protected from much predation. Killer whales and large sharks may target Sowerby's beaked whales.
Nothing is known about the mating systems of M. bidens.
Little in known about general reproductive behavior of M. bidens. Mating is thought to occur in late winter, with births late in spring and gestation lasting about 12 months. Young are about 2.4 to 2.7 meters in length and weigh about 185 kg.
Breeding interval: Breeding interval is not known for Sowerby's beaked whales.
Breeding season: Mating is thought to occur in late winter.
Average number of offspring: 1.
Average gestation period: 12 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Sowerby's beaked whale females provide milk for their young and protect them. There is no other available information on parental investment.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
