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Overview

Brief Summary

Description

"More than 50 Gervais’s beaked whales have been found stranded along the coast of the United States. The holotype of this species - the individual that was identified as a separate species, and named - was found floating in the English Channel in about 1840, and the name ""europeaus"" was applied, but since then, only one more has been reported from European waters. The whales apparently live in deep tropical to warm temperate waters of the Atlantic Ocean. They have dark gray backs and paler gray bellies; juveniles' bellies are white. As with other species in this genus, not much is known about them. Six whales have been weighed, and the weights ranged from 49 kg for a 1.62 m-long calf to 1,178 kg for a female that was 3.71 m in length."

Links:
Mammal Species of the World
  • Original description: Gervais, 1855.  Histoire Naturelle des Mammifères, 2:320.
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Biology

This species is assumed to be a deep diver (6) that only comes close to the shore to give birth, as many strandings are females with their newborn calves, and sightings of this whale are extremely rare (5). Gervais' beaked whale is nearly impossible to distinguish from other beaked whales when sighted at sea (2). Females are thought to be larger than males, becoming sexually mature at 4.5 m and giving birth to highly dependent young of just 2.1 m. The species is known to live to at least 27 years in the wild (2). They are thought to live in couples or small groups, and fighting between males is assumed to occur as stranded males are highly scarred. However, the distinctive tooth marks of the cookie-cutter shark and the orca have been seen on individuals as well. The stomach, which has unexplained multiple chambers, has been found to contain mainly squid, in addition to deep sea shrimp and viper fish (2).
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Description

Gervais' beaked whale has a prominent, slender beak with only two teeth which, whilst obvious in males, are not visible in females (5). These whales are dark grey to black on the back, fading to light grey or white on the underside. The head is relatively small with a slightly bulging forehead and the dorsal fin is situated towards the tail end of the back (2) (5).
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Comprehensive Description

Description

 Gervais' beaked whale Mesoplodon europaeus is a toothed whale and can be recognised as such by the single blowhole and the presence of teeth (rather than baleen). It is a member of the beaked whale family with the characteristic V-shaped crease on the throat and the short dorsal fin set relatively far back. Gervais' beaked whale is a small beaked whale that can reach up to 5.5 m in length. The lower jaw has a single pair of teeth (exposed only in adult males). The forehead rises at a shallow angle. It has a distinct beak and the mouthline is curved down at rear. Gervais' beaked whale has a charcoal grey dorsal and lateral colouration with a lighter belly. Adults may have clear scratches and scars on the body.Gervais' beaked whale may be confused with True's beaked whale Mesoplodon mirus but it has conspicuously smaller flippers. Gervais' beaked whales are usually found either alone or in small groups. Very little is known about their behaviour and dive duration due to the relative lack of sightings (Kinze, 2002).
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Species Description

Gervais' beaked whales, sometimes called the "Antillean" or "Gulf Stream beaked whale," are little known members of the beaked whale family (Ziphiidae) (Reeves et al. 2002). As adults, Gervais' beaked whales can reach estimated lengths of about 15-17 ft (4.6-5.2 m) and weigh at least 2,640 lbs (1200 kg). Females may be slightly larger than males. Males can be distinguished from females and juveniles by a pair of visible teeth that erupt from the front portion of the bottom jaw. Females and juveniles have teeth as well, but they remain hidden beneath the gum tissue of the mouth. The jawline is typically straight or slightly curved.

Gervais' beaked whales have a relatively small to medium size body with a moderately long beak and an indistinct sloping "melon". They have a small, triangular, wide-based, slightly "falcate", "dorsal" fin located far down (about two-thirds) the animal's back. The coloration of the body is dark gray or bluish to black with a paler ventral side. Animals tend to become darker as they age. Mature males may also have linear scars from battles over females. This species of beaked whale is difficult to observe and identify at sea due to a low profile at the surface and a small, inconspicuous blow.

Many species of beaked whales (especially those in the genus Mesoplodon) are very difficult to distinguish from one another (even when dead). At sea, they are challenging to observe and identify to the species level due to their cryptic, skittish behavior, a low profile, and a small, inconspicuous blow at the waters surface; therefore, much of the available characterization for beaked whales is to genus level only. Uncertainty regarding species identification of beaked whales often exists because of a lack of easily discernable or distinct physical characteristics.

Gervais' beaked whales are usually found individually or in small closely associated social groups. While diving, they use suction to feed mainly on cephalopods (e.g., squid), mysid shrimp, and small fish in deep water.

Females may become sexually mature at 15 ft (4.5 m). A sexually mature female will give birth to a single newborn calf that is about 7 ft (1.6-2.2 m) long and weighs about 176 lbs (80 kg). The estimated lifespan of this species is at least 27 years, but may be up to 48 years (Reeves et al. 2002).

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Distribution

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

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National Distribution

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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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).

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Warm-temperate to tropical waters of Atlantic.
  • North-West Atlantic Ocean species (NWARMS)
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Range Description

Although sometimes depicted as a North Atlantic endemic, this species is probably continuously distributed in deep waters across the tropical and temperate Atlantic Ocean, both north and south of the equator (Mead 1989; MacLeod et al. 2006). Most records are from the east and Gulf coasts of North America, from New York to Texas, but Gervais' beaked whales are also known from several of the Caribbean islands. This is the most commonly-stranded beaked whale in the southeastern United States. In the eastern Atlantic, they are known from Ireland to Guinea-Bissau in West Africa. There is only one record of this species entering the Mediterranean, and it is considered a vagrant (Podesta et al. 2005). There are also strandings at Ascension Island in the central South Atlantic (Mead 1989), and along the coast of Brazil (de Oliveira Santos et al. 2003). There is speculation that its Southern Hemisphere distribution could extend to Uruguay and Angola .
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Geographic Range

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 )

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Range

Although the first specimen of this species was found in the English Channel, it has only been found in the Atlantic Ocean since. The range has been deduced from stranding sites, and is possibly inaccurate, but is thought to stretch from New York to Trinidad on the western side of the Atlantic and from Ireland to Guinea Bissau on the eastern side (2).
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Stranding Distribution

The majority of stranding records for this species occur in the western North Atlantic along the eastern seaboard of the United States. Strandings have occurred to a lesser extent in the Caribbean and Gulf of Mexico. Despite its name, only a few specimens have stranded in European waters. Other eastern Atlantic stranding locations include the Canary Islands and Guinea-Bissau. South Atlantic Ocean records are reported from Namibia, Brazil and Ascension Island. It appears to prefer the deeper waters of the tropical and warm temperate Atlantic.

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Gervais' beaked whales are distributed throughout deep, warm waters of the central and north Atlantic Ocean. This species is thought to occur mostly north of the equator. Their range includes the English Channel, Europe, Canaries Islands, Western Africa, Brazil, Caribbean Sea, Gulf of Mexico, and the eastern north Atlantic (Jefferson et al. 2008). There are no known seasonal movements or migrations for this species.

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Physical Description

Morphology

Physical Description

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

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Tooth morphology

Tooth position

A single pair of teeth are positioned back from the apex of lower jaw about 1/3 the total length of the mouthline. The root base is square and not inclined in the jaw.

Tooth exposure

Erupted teeth in adult males are covered by gum tissue, with only the tip of tooth exposed. Teeth of females and juveniles do not erupt.

Tooth shape

In lateral profile, the anterior margin is relatively straight for a majority of its length and concave distally; the posterior tooth margin is weakly convex.

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Skull morphology

Diagnostic features of the skull and mandible

On the vertex of the dorsal skull the premaxillary bone extends forward of the nasal and frontal bones. Separates from Berardius and Ziphius.

A sulcus (groove) running along the middle of the combined surfaces of the nasal bones so depresses their combined middle that it is the lateral portion of each nasal bone that reaches farthest forward on the vertex. Separates from Tasmacetus and Indopacetus.

When the skull is upright and the long axis of the anterior half of the beak is horizontal, a horizontal plane transecting the summit of either maxillary prominence transects the mesethmoid bone. Separates from Hyperoodon.

Tooth alveoli of mandible overlap the mandibular symphysis. Separates from Berardius, Ziphius, Tasmacetus, Indopacetus, Hyperoodon, M. bowdoini, M. carlhubbsi, M. densirostris, M. ginkgodens, M. hectori, M. layardi, M. mirus, M. perrini, M. peruvianus, M. stejnegeri, and M. traversi.

Basirostral groove absent or present as a shallow groove that does not extend past the prominental notch. Separates from M. grayi.

Jugal bone curves around anterior of maxillary. Separates from M. bidens.

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External morphology

Head Shape

The small forehead is defined posteriorly by the indentation at blowhole. The melon merges seamlessly to the narrow, moderate length rostrum. The mouthline is relatively straight.

Coloration

Adult males are dark gray dorsally and medium gray ventrally with pectoral fins uniformly dark gray above and below. Scarring is often readily visible and appears to be more prevalent in adult males and can occur in round, oval or linear patterns. Oval scars may result from cookie cutter sharks and linear lines from conspecifics given the placement of mandibular teeth. Female pigmentation is similar to adult males, some adult females display a patch of white about 15 cm in diameter that extends from just anterior to the genital slit to a point just posterior to the anus. This patch has not been observed in males. Juveniles have a white belly.

Size

Adult body length ranges between 4.5 to 4.9 m. Recorded maximum body length for adult males and females is 4.8 m and 4.9, respectively. Length at birth is approximately 2.1 m.

Most Likely Confused With:

Mesoplodon bidens

Mesoplodon mirus

Ziphius cavirostris

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Size

Length: 450 cm

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Size in North America

Sexual Dimorphism: Females are thought to be larger than males.

Length:
Range: up to 4.6 m males; up to 5.2 m females

Weight:
Range: 1,178 kg female
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Ecology

Habitat

Habitat Type: Marine

Comments: Presumably mainly pelagic; known primarily from strandings.

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oceanic
  • UNESCO-IOC Register of Marine Organisms
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Habitat and Ecology

Habitat and Ecology
The favored habitat of Gervais' beaked whales appears to be warm temperate and tropical waters (Norman and Mead 2001). Like other members of the genus, the species prefers deep waters based on the presence of prey from such habitats in stomach contents and a lack of sightings near shore (Mead 1989). Strandings and the few possible sightings suggest that the species prefers tropical and subtropical waters (MacLeod et al. 2006).

Like other members of the genus, Gervais’ beaked whales are known to feed primarily on squid, although some fish may be taken as well (Norman and Mead 2001). There is also a record of a mysid shrimp found in the stomach of a stranded specimen. Stable isotope analysis has found that this species feeds at a similar trophic level to other Mesoplodon species with which it is sympatric, but at lower trophic level than Cuvier’s beaked whale which suggests that it feeds on smaller prey than this latter species (MacLeod et al. 2005).

Systems
  • Marine
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Mesoplodon europaeus lives in warm to tropical pelagic waters.

(Cetacea, 2001; Debrot and Barros, 1992)

Aquatic Biomes: pelagic

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Depth range based on 12 specimens in 1 taxon.
Water temperature and chemistry ranges based on 11 samples.

Environmental ranges
  Depth range (m): 0 - 0
  Temperature range (°C): 17.743 - 27.172
  Nitrate (umol/L): 0.304 - 1.003
  Salinity (PPS): 32.419 - 36.416
  Oxygen (ml/l): 4.623 - 5.571
  Phosphate (umol/l): 0.057 - 0.336
  Silicate (umol/l): 1.539 - 2.466

Graphical representation

Temperature range (°C): 17.743 - 27.172

Nitrate (umol/L): 0.304 - 1.003

Salinity (PPS): 32.419 - 36.416

Oxygen (ml/l): 4.623 - 5.571

Phosphate (umol/l): 0.057 - 0.336

Silicate (umol/l): 1.539 - 2.466
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

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 Gervais' beaked whale is an oceanic and coastal species that may be seen at the surface but little is known on what depth they may dive to.
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Inhabits warm to tropical pelagic waters (2).
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Gervais' beaked whales prefer deep tropical, subtropical, and warm temperate waters of the Atlantic Ocean, but are occasionally found in colder temperate seas.

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Migration

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.

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Trophic Strategy

Comments: Diet includes squids.

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Food Habits

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 )

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Associations

Predation

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:

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Known predators

Mesoplodon europaeus is prey of:
Isistius
Orcinus orca

This list may not be complete but is based on published studies.
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Known prey organisms

Mesoplodon europaeus preys on:
non-insect arthropods
Actinopterygii
Mollusca
Crustacea

This list may not be complete but is based on published studies.
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Life History and Behavior

Life Expectancy

Lifespan/Longevity

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.

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Lifespan, longevity, and ageing

Maximum longevity: 48 years (wild) Observations: One specimen may have been over 48 years old (Ronald Nowak 2003).
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Reproduction

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)

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Conservation

Conservation Status

National NatureServe Conservation Status

United States

Rounded National Status Rank: N2 - Imperiled

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NatureServe Conservation Status

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.

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IUCN Red List Assessment


Red List Category
DD
Data Deficient

Red List Criteria

Version
3.1

Year Assessed
2008

Assessor/s
Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L.

Reviewer/s
Hammond, P.S. & Perrin, W.F. (Cetacean Red List Authority)

Contributor/s

Justification
There is little information on abundance and none on trends in abundance for this species. It is not believed to be uncommon but it is potentially vulnerable to low-level threats and a 30% global reduction over three generations cannot be ruled out (criterion A).

History
  • 1996
    Data Deficient
  • 1994
    Insufficiently Known
    (Groombridge 1994)
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IUCN Red List of Threatened Species: data deficient

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Status

Gervais' beaked whale is classified as Data Deficient (DD) on the IUCN Red List 2004 (1), and is listed on Appendix II of CITES (4). All cetaceans (whales and dolphins) are listed on Annex A of EU Council Regulation 338/97; they are therefore treated by the EU as if they are included in CITES Appendix I, so that commercial trade is prohibited.
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Population

Population
No estimates of abundance exist for the species; however, estimates indicate that 106 (CV=41%) beaked whales of the genus Mesoplodon occur in the northern Gulf of Mexico, considered to be either M. densirostris or M. europaeus (Mullin and Fulling, 2004). Based on the frequency with which they strand, they are presumed to be relatively common in waters along the east coast of North America.

Population Trend
Unknown
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Population Trends

For management purposes, Gervais' beaked whales inhabiting U.S. waters have been divided into the Western North Atlantic stock and the Northern Gulf of Mexico stock. The estimated population for Mesoplodon spp. (Blainville's and Gervais' beaked whales) in the Northern Gulf of Mexico is 75-100 animals. This stock is considered "strategic" due to the uncertainty surrounding its status. No current population estimates are available for the Western North Atlantic stock of this species of beaked whale, but based on the number of strandings, they may be fairly common along the U.S. Atlantic coast. There are insufficient data to determine the population trends for this species.

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Threats

Comments: Unknown.

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Major Threats
This species, like other beaked whales, is likely to be vulnerable to loud anthropogenic sounds, such as those generated by navy sonar and seismic exploration (Cox et al. 2006).

In particular, several atypical mass strandings of beaked whales, including Gervais' beaked whales, were associated with naval activities: mid to late 1980s on the Canary Islands (Waring et al. 2006), in March 2000 on the Bahamas (Rowles et al. 2000, Anonymous 2001) and again in September 2002 during a naval NATO manoeuvre involving low frequency sonar around the Canaries (Vidal pers. comm.).

Evidence from stranded individuals of several species, including Mesoplodon europaeus, indicates that they have swallowed discarded plastic items, which may eventually lead to death (e.g. Scott et al. 2001).

Direct hunting has never been associated with this species. Pervasive gillnet and longline fisheries throughout the species' range raises concern that some bycatch is likely. Even low levels of bycatch might cause unsustainable impacts on this group of naturally rare cetaceans.

Predicted impacts of global climate change on the marine environment may affect this species of whale, although the nature of impacts is unclear (Learmonth et al. 2006).
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The main threats to Gervais' beaked whale are accidental entanglement in gillnets and acoustic trauma following military noise pollution underwater (1). In the mid to late 1980s, several mass strandings were thought to be associated with naval activities around the Canary Islands. Later, between 1992 and 1998, 28 Gervais' beaked whales were stranded along the US coast between Florida and Massachusetts, followed by more mass strandings in September 2002 after NATO tested low frequency sonar (7).
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Gervais' beaked whales have been incidentally taken as bycatch in fishing gear, such as pound nets off the U.S. Atlantic coast and potentially in driftnets and gillnets. This species may be captured in the Caribbean Sea for food. This species of beaked whale may be sensitive to underwater sounds and anthropogenic noise. Anthropogenic noise levels in the world's oceans are an increasing habitat concern, particularly for deep-diving cetaceans like Gervais' beaked whales that use sound to feed, communicate, and navigate in the ocean.

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Management

Biological Research Needs: Obtain basic life history information.

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Conservation Actions

Conservation Actions
The species is listed in Appendix II of CITES. Research is needed to determine the impacts of potential threatening processes on this species.
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Conservation

There are no special conservation plans for this species, although trade in this species is limited by CITES around the world and prohibited in Europe.
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Relevance to Humans and Ecosystems

Risks

IUCN Red List Category

Data Deficient (DD)
  • IUCN (2008) Cetacean update of the 2008 IUCN Red List of Threatened Species.
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Wikipedia

Gervais' beaked whale

Gervais' beaked whale!<-- This template has to be "warmed up" before it can be used, for some reason -->

Gervais' Beaked Whale (Mesoplodon europaeus), sometimes known as the Antillian Beaked Whale, Gulf Stream Beaked Whale, or European Beaked Whale (from which its scientific name is derived) is the most frequently stranding type of Mesoplodont whale off the coast of North America. It has also stranded off South America and Africa.

Contents

Physical description

This species is the largest of the mesoplodonts and rather gracile, elongated, and laterally compressed compared with the others. The mouthline is remarkably straight, even in males, and the two teeth of the male erupt towards the tip of the beak, and are hardly noticeable. The head is overall small and tapering in outline. The melon only bulges very slightly. The coloration is dark gray on top and lighter gray on bottom. Females sometimes have lighter spots near the genitals and face, with a dark circle remaining around the eyes. Juveniles start off with a lighter coloration, but soon darken. Males are 4.5 meters (15') in length and females are at least 5.2 meters (17') and probably weigh more than 1200 kg (2600 pounds). Calves are believed to be 2.1 meters (7 feet) in length. One beached specimen may have been 48 years old.

Population and distribution

The first stranding occurred in England, but it has since been found off Ireland, the Canary Islands, Western Africa, and Ascension Island. In August 2001, a specimen was found off São Paulo, Brazil; the southernmost specimen found to date.[citation needed] The species is believed to be naturally rare, and no estimates have been attempted.

It is remarkable that although this species frequently strands (the first occurring in 1840), until 1998 no human had seen a living specimen. Since then only ten other sightings have occurred.[citation needed]

Behavior

Judging by beachings, the whales inhabit small groups. They probably feed on squid.

They can dive deep : the first sighting in 1998 (west of the island of Tenerife) involved three whales at a depth of 1500 meters.

Another small group was seen south of the island of Gran Canaria : Although timid, the whales allowed close photos. It was reported that they surfaced for short time, and that their dives lasted for around an hour. [1]

In September 2008, northeast of the island of Lanzarote, some Gervais' beaked whales were photographed breaching out of the water.[2]

Conservation

The species has not been hunted and only very infrequently gets tangled up in fishing nets.

References

  • Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. (2008). Mesoplodon europaeus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 24 March 2009. Database entry includes a brief justification of why this species is of data deficient.
  • Encyclopedia of Marine Mammals. Edited by William F. Perrin, Bernd Wursig, and J.G.M Thewissen. Academic Press, 2002. ISBN 0-12-551340-2
  • Sea Mammals of the World. Written by Randall R. Reeves, Brent S. Steward, Phillip J. Clapham, and James A. Owell. A & C Black, London, 2002. ISBN 0-7136-6334-0
  • A Gervais' beaked whale (Mesoplodon europaeus) washed ashore in southeastern Brazil: extra limital record? Santos, Zampirolli, Castro, and Alarenga. Aquatic Mammals 2003. 29.3, 404-410. Available: here
  • Red Canaria de Varamientos (Vonk & Martín 1988; Martín & Carrillo, 1992; Martín et al. 1995;Carrillo & Martín, 2000; Carrillo & Tejedor, 2002, 2003, 2004)
  • Estudios aplicados a la conservación de las poblaciones de cetáceos en la provincia de Santa Cruz de Tenerife. Informe para el Gobierno de Canarias by Carrillo, M. and Tejedor M. 2002 (Tenerife Conservación - Biblioteca pública del Centro de Planificación Ambiental de la Laguna – Tenerife)
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Notes

Did you know?

· Gervais' beaked whales may be the most commonly sighted species of Mesoplodont off the U.S. Atlantic coast and the Gulf of Mexico.

· Gervais' beaked whales are the most common species of the genus Mesoplodon to strand on the U.S. southeastern Atlantic coast.

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Did you know?

· Gervais' beaked whales may be the most commonly sighted species of Mesoplodont off the U.S. Atlantic coast and the Gulf of Mexico.

· Gervais' beaked whales are the most common species of the genus Mesoplodon to strand on the U.S. southeastern Atlantic coast.

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