Mesoplodon bowdoini

Geographic Range

Mesoplodon bowdoini , also known as Andrew's beaked whales, can be found in cool temperate water such as the Indo-Pacific Ocean. The waters around New Zealand and off the southern coast of Australia are home to this whale.

• Biogeographic Regions
• indian ocean
  • native native
• pacific ocean pacific ocean
  • native native

Habitat

These animals prefer to forage at depths below the 1000 meter line. This is possibly due to the distribution of squid and other food sources not yet identified. The great depths to which these mammals travel can result in dives that last longer then 45 minutes.

• Habitat Regions
• temperate temperate

• Aquatic Biomes
• pelagic pelagic
• coastal coastal

Physical Description

There have been very few sightings of this whale due to its spending little time on the surface. Of the roughly 35 specimens studied, the following is specific to M. bowdoini : indiviuals weigh 2.6 tons at their maximum and at birth the average length is approximately 2 meters. Females grow to an average of 4.6 m., with males growing slightly longer to 4.8 m. The color of males ranges from dark grayish-blue to black, except for the "beak", the tip of the rostrum and lower jaw, which are white in color. Females have more of an off-white beak.

Andrew's whale females or young are distinguished from other Mesoplodon species by their heads, which have a small melon and as a result, slants down dramatically from the body. Also, females and young have short, thick beaks. The dorsal fin of this species is rather small for its body size. This fin is found in the middle of the back, and it is triangular and blunt tipped.

The teeth of males are helpful in identification. Males have two teeth located in the lower jaw within a set of sockets in the middle of the beak. Females also contain these teeth, but they are not visible since they do not erupt through to the surface.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger

Reproduction

Due to the lack of scarring in M. bowdoini investigators believe that there is no physical competition for partners. Little is known about the mating system of this species.

The only information on the reproductive system of M. bowdoini is from occasional observations of young. The calving season occurs during the summer and autumn.

• Key Reproductive Features
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

No specific information is available. As mammals, females nurse their young.

• Parental Investment
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female

Lifespan/Longevity

No information available.

Behavior

Little is known about the behavior of this whale. Andrew's beaked whales are slow, sluggish marine mammals. Beaked whales have "flipper pockets," which allow the flippers to be tucked away to reduce drag when swimming. M. bowdoini spends little time at the surface, making individulas more difficult to identify or find. When spotted, these whales are generally alone and if in a group it is with no more then 6 others.

• Key Behaviors
• natatorial natatorial
• motile motile
• solitary solitary

Home Range

No information is available.

Communication and Perception

No information is known.

• Perception Channels
• tactile tactile
• chemical chemical

Food Habits

Mesoplodon bowdoini feeds in deep waters primarily on squid . When squid are not available fish become a secondary source of food.

• Primary Diet
• carnivore carnivore
  • piscivore piscivore
  • molluscivore molluscivore

• Animal Foods
• fish
• mollusks

Predation

No information is known about predation.

Ecosystem Roles

Mesoplodon bowdoini affects the environment by feeding on squid and occasionally fish, which may affect their populations. No relationships with other marine animals are known.

Economic Importance for Humans: Positive

There are no known positive affects of M. bowdoini on humans. These animals are not significant to the whaling industry.

Economic Importance for Humans: Negative

There are no known adverse affects of M. bowdoini on humans.

Conservation Status

M. bowdoini is protected under the 1972 Marine Mammal Protection Act(MMPA). This established an end to the hunting, harassing, capture or killing of marine mammals in US waters and by US citizens. MMPA also extended the ban on the importation of marine mammals or their products into the country.

Other Comments

This animal is very similar to many other beaked whales. Due to their lack of surface time and strandings, these whales are very poorly known.

Additional Links

Encyclopedia of Life

Contributors

Matthew Wund (editor), University of Michigan-Ann Arbor.

angela mangano (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Baker, A. 2001. Status, relationships, and distribution of Mesoplodon bowdoini Andrews, 1908 (Cetacea: Ziphiidae). Marine Mammal Science , 17(3): 473-493.

Culik, B. 2003. "Convention of Migratory Species (CMS)" (On-line). Mesoplodon bowdoini Andrews, 1908. Accessed October 07, 2004 at http://www.cms.int/reports/small_cetaceans/data/m_bowdoini/m_bowdoini.htm .

Jefferson, T., S. Leatherwood, M. Webber. 1993. FAO Species Identification Guide: Marine Mammals of the World . Rome, Italy: Food and Agriculture Organization.

Reeves, R., B. Stewart, P. Clapham, J. Powell. 2002. Sea Mammals of the World . London: A & C Black.

U.S. Department of the Interior. 2003. "Marine Mammal Protection Act" (On-line). Minerals Management Service Environmental Program. Accessed March 09, 2004 at http://www.mms.gov/eppd/compliance/mmpa/ .

1975. The Toothed Whales. Pp. 457, 496 in Grzimek's Animal Life Encyclopedia , Vol. Mammals II, Second Edition. New York: Van Nostrand Reinhold Company.