Mesoplodon europaeus is known only from strandings, so the known distribution may be affected by ocean currents and efforts in North America to retrieve stranded animals. Recorded from as far north as New York and as far south as Trinidad, Mesoplodon europaeus is probably the most abundant member of its genus in the Gulf of Mexico. Records from the eastern side of the Atlantic are more spotty, ranging from Ireland to Guinea Bissau in Africa. A relationship has been suggested between water temperature and prey species distribution, thus affecting the distribution of different Mesoplodon species.

(McLeod, 2000a; Robineau and Vely, 1993)

Biogeographic Regions: atlantic ocean (Native )

occurs (regularly, as a native taxon) in multiple nations

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Known from strandings in the Atlantic, where warm temperate and subtropical waters seem to be favored; may be closely associated with the Gulf Stream; known from strandings in Ireland, Canary Islands, western Africa, on Ascension Island (south of the equator), and the east coast of North America, from New York to Florida and Texas, the Caribbean region, and Trinidad (Leatherwood and Reeves 1983; IUCN 1991; Mead and Brownell, in Wilson and Reeder 1993).

The coloration of Mesoplodon europaeus is black or dark grey on the back fading to a lighter gray on the sides and belly. For a cetacean, the head is small with respect to total body size. The tails of ziphiids (beaked whales) are unusual among cetaceans in having no notch in the center of the fluke. Some stranded specimens, particularly adult males, have many scars on their bodies, presumably from sharks and fighting between males.

Nearly all ziphiids have a greatly reduced number of teeth, and Mesoplodon europaeus has only two in the lower jaw. These two teeth are are visible outside the mouth as small “tusks” near the front of the rostrum. Conchoderma, stalked barnacles, often attach themselves to these teeth. Tusk shape varies between species and it has been proposed that these difference evolved in order to aid the animals in differentiating their own species, as Mesoplodon species are otherwise very similar in appearance. It is extremely difficult to distinguish the similar-looking species of this genus by sightings, and sometimes even when using the diagnostic characters of the skull.

(Lynn and Ross, 1992; Martin et al, 1990; McLeod, 2000b; Robineau and Vely, 1993; Vaughn et al, 2000; Pitman, 2001)

Range mass: 1200 + (high) kg.

Range length: 4 to 5.2 m.

Other Physical Features: endothermic ; bilateral symmetry

Length: 450 cm

• Marine

Mesoplodon europaeus lives in warm to tropical pelagic waters.

(Cetacea, 2001; Debrot and Barros, 1992)

Aquatic Biomes: pelagic

Habitat Type: Marine

Comments: Presumably mainly pelagic; known primarily from strandings.

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

From stomach contents of stranded M. europaeus it is known that they eat primarily squid (Octopoteuthis spp., Mastigoteuthis spp. and Taonius spp.), deep sea shrimp(Neognathophausia ingens) and mesopelagic viper fish (Chauliodus schmidti and Nesiarchus nasutus). The stomach is divided into multiple chambers. The purpose of this is undetermined, as squid and fish are easily digested, as opposed to the tough material eaten by most animals with such stomach morphology.

(Vaughn et al, 2000; Debrot and Barros, 1992; Martin et al, 1990)

Animal Foods: fish; mollusks; aquatic crustaceans

Primary Diet: carnivore (Piscivore , Eats non-insect arthropods, Molluscivore )

Comments: Diet includes squids.

From distinctive scars on some stranded beaked whale specimens it is known that cookie-cutter sharks do attack M. europaeus. The whale probably uses its tusks to protect itself from this and other predators, as well as for interspecific fighting.

(Pitman, 2001)

Known Predators:

• killer whales (Orcinus orca)
• cookie-cutter sharks (Isistius)

Gervais' beaked whale is known to live to at least 27 years old in the wild.

(Pitman, 2001)

Range lifespan

Status: wild: 27 (high) years.

Average lifespan

Status: captivity: 48 years.

Very little information is available, but females are thought to be sexually mature by the time they reach 4.5 m size.

(Martin et al, 1990; Poss, 1998; Pitman, 2001)

Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); viviparous

As with all cetaceans, the young are necessarily precocial at birth and Mesoplodon europaeus are about 2.1 m long at birth.

Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)

IUCN Red List of Threatened Species: data deficient

United States

Rounded National Status Rank: N2 - Imperiled

Rounded Global Status Rank: G3 - Vulnerable

Reasons: Known from strandings in the Atlantic, where warm temperate and subtropical waters seem to be favored; may be closely associated with the Gulf Stream; conservation status is poorly known.

Comments: Unknown.

Biological Research Needs: Obtain basic life history information.