Species

Peruvian beaked whale

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Peruvian beaked whales. Source: NOAA National Marine Fisheries Service

Peruvian beaked whale (also well known as the pygmy beaked whale and Lesser Beaked Whale; scientific name: Mesoplodon peruvianus) is one of 21 species of beaked whales (Hyperoodontidae or Ziphiidae), medium-sized whales with distinctive, long and narrow beaks and dorsal fins set far back on their bodies. They are marine mammals within the order of cetaceans.

caption Pygmy beaked whale (Mesoplodon peruvianus) Source: NOAA NMFS SWFSC PRD
 

Conservation Status:
Data Deficient

Scientific Classification

Kingdom: Animalia
Phylum:--- Chordata
Class:------ Mammalia
Order:-------- Cetacea
Family:-------- Hyperoodontidae
Genus:--------- Mesoplodon
Species:-------- Mesoplodon peruvianus (Reyes, Mead and Van Waerebeek, 1991)

Common Names:
Lesser beaked whale
Peruvian beaked whale
Pygmy beaked whale

The Peruvian beaked whale was discovered in Peru in 1991 and is only known in Peruvian waters, although there have been two documented strandings on Mexican shores).

Little is known about Peruvian beaked whale due to its inaccessible habitat and elusive nature. The blow of the Peruvian beaked whale is also inconspicuous, making it hard to spot (Cetacea, 2001). The species avoids watercraft and can be mistaken for members of other Mesoplodon species. It is sometimes mistaken for Hector's beaked whale.

Scientists have examined 13 dead specimens, and few reliable sightings have been recorded. All recorded strandings have involved single individuals, but the species can be spotted in groups of two to three, with the third usually being a calf.

Physical description

At birth, the Peruvian beaked whale is between 1.5-1.6 meters (m) long, while the adult is between 3.4-3.7 m. This whale is the smallest species of Mesoplodon (World Biodiversity Database, 2001).

This species is, on its upper side, uniformly dark gray fading to light gray on the underside (dark gray posterior to the navel). The body is spindle-shaped. The short, dark-tipped beak precedes a narrow head with an indentation at the blowhole.

This species has two tiny teeth on its lower jaw. The small, triangular dorsal fin has a wide base and is positioned far behind the center of this marine mammal. The flukes have no notches, and their tips are slightly pointed. (All information from Texas A&M University - Corpus Christi, 2001 unless otherwise noted.)

The  Peruvian beaked whale exhibits sexual dimorphism. The males of the species are larger than the females (World Biodiversity Database, 2001).

Other Physical Features: Endothermic; Bilateral symmetry
 

Distribution and movements

Strandings and captures have taken place between 11 and 15 degrees south latitude, off the coast of central and southern Peru. This is thought to be the southern end of the range of Peruvian beaked whale (Texas A&M University - Corpus Christi, 2001)

However, "there is a single record of a stranding in New Zealand (Baker and Van Helden 1999), possibly suggesting that this species may have a more extensive distribution than previously believed. Alternatively, the New Zealand record may be an extralimital wandering." (IUCN)

Habitat

This species lives in mid- to deep-sea waters off of the Peruvian coast.

Habitat Regions: Tropical; Saltwater or marine

Aquatic Biomes: Pelagic

Feeding habits

Although feeding by the Peruvian beaked whale has not been witnessed, it is believed that this species eats mid- to deep-sea fish and squid (Cetacea, 2001).

Animal Foods: Fish; Mollusks

Predation

Humans are the only known threat to the Peruvian beaked whale. This whale becomes tangled in fishing nets, which initially led to the discovery of this species

Threats and conservation status

The IUCN Red List reports:

Some pygmy beaked whales are caught incidentally in drift gillnets for sharks off Peru (Reyes et al. 1991).. Entanglement in fishing gear, especially gillnets in deep water (e.g., for billfish and tuna), is probably the most significant threat.

There is no information on global abundance or 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

In recent years, there has been increasing concern that loud underwater sounds, such as active sonar and seismic operations, may be harmful to beaked whales (Malakoff 2002). The use of active sonar from military vessels has been implicated in mass strandings of a number of beaked whales including several Mesoplodon species and Indopacetus pacificus (Balcomb and Claridge 2001, Jepson et al. 2003, Cox et al. 2006, Wang and Yang 2006). Sound impacts may be important for all ziphiid species.

Pygmy beaked whales have been recorded ingesting plastic items, which may eventually lead to death (e.g. Scott et al. 2001).
Potential 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).

Further reading

  1. Mesoplodon peruvianus Reyes, Mead and Van Waerebeek, 1991. Encyclopedia of Life. Accessed 12 May 2011.
  2. Bhatia, J. 2002. "Mesoplodon peruvianus" (On-line), Animal Diversity Web. Accessed May 12, 2011 .
  3. 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 peruvianus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. . Downloaded on 15 May 2011.
  4. Baker, A. N. and Van Helden, A. L. 1999. New records of beaked whales, genus Mesoplodon, from New Zealand (Cetacea: Ziphiidae). Journal of the Royal Society of New Zealand 29: 235-244.
  5. Balcomb, K. C. and Claridge, D. E. 2001. A mass stranding of cetaceans caused by naval sonar in the Bahamas. Bahamas Journal of Science 8(2): 2-12.
  6. Barlow, J. 1999. Trackline detection probability for long-diving whales. In: G. W. Garner, S. C. Amstrup, J. L. Laake, B. J. F. Manley, L. L. McDonald and D. G. Robertson (eds), Marine mammal survey and assessment methods, pp. 209-221. Balkema Press, Netherlands.
  7. Cetacea, 2001. "Cetacea: *Mesoplodon peruvianus* (Lesser beaked whale)" (On-line). Accessed November 17, 2001.
  8. Cox, T. M., Ragen, T. J., Read, A. J., Vos, E., Baird, R. W., Balcomb, K., Barlow, J., Caldwell, J., Cranford, T., Crum, L., D'Amico, A., D'Spain, A., Fernández, J., Finneran, J., Gentry, R., Gerth, W., Gulland, F., Hildebrand, J., Houser, D., Hullar, T., Jepson, P. D., Ketten, D., Macleod, C. D., Miller, P., Moore, S., Mountain, D., Palka, D., Ponganis, P., Rommel, S., Rowles, T., Taylor, B., Tyack, P., Wartzok, D., Gisiner, R., Mead, J. and Benner, L. 2006. Understanding the impacts of anthropogenic sound on beaked whales. Journal of Cetacean Research and Management 7(3): 177-187.
  9. Ferguson, M. C. and Barlow, J. 2001. Spatial distribution and density of cetaceans in the eastern Pacific Ocean based on summer/fall research vessel surveys in 1986-96. Southwest Fisheries Science Center Adminstrative Report LJ-01-04: 61 pp.
  10. Fernández, A., Edwards, J. F., Rodriguez, F., Espinosa, A., De Los Monteros, Herraez, P., Castro, P., Jaber, J. R., Martin, V. and Arebelo, M. 2005. "Gas and fat embolic syndrome" involving a mass stranding of beaked whales (family Ziphiidae) exposed to anthropogenic sonar signals. Veterinary Pathology 42: 446-457.
  11. Gomercic, H., Gomercic, M. D., Gomericic, T., Lucic, H., Dalebout, M., Galov, A., Skrtic, D., Curkovic, S., Vukovic, S. and Huber, D. 2006. Biological aspects of Cuvier's beaked whale (Ziphius cavirostris) recorded in the Croatian part of the Adriatic Sea. European Journal of Wildlife Research 52(3): 182-187.
  12. Gordon, D. (Ed.) (2009). New Zealand Inventory of Biodiversity. Volume One: Kingdom Animalia. 584 pp
  13. IUCN (2008) Cetacean update of the 2008 IUCN Red List of Threatened Species.
  14. Jepson, P. D., Arebelo, M., Deaville, R., Patterson, I. A. P., Castro, P., Baker, J. R., Degollada, E., Ross, H. M., Herraez, P., Pocknell, A. M., Rodriguez, F., Howie, F. E., Espinosa, A., Reid, R. J., Jaber, J. R., Martin, V., Cunningham, A. A. and Fernandez, A. 2003. Gas-bubble lesions in stranded cetaceans. Nature 425: 575-576.
  15. Learmonth, J. A., Macleod, C. D., Santos, M. B., Pierce, G. J., Crick, H. Q. P. and Robinson, R. A. 2006. Potential effects of climate change on marine mammals. Oceanography and Marine Biology: An Annual Review 44: 431-464.
  16. Macleod, C. D., Perrin, W. F., Pitman, R. L., Barlow, J., Balance, L., D'amico, A., Gerrodette, T., Joyce, G., Mullin, K. D., Palka, D. L. and Waring, G. T. 2006. Known and inferred distributions of beaked whale species (Ziphiidae: Cetacea). Journal of Cetacean Research and Management 7(3): 271-286.
  17. Malakoff, D. 2002. Suit ties whale deaths to research cruise. Science 298: 722-723.
  18. Mead, James G., and Robert L. Brownell, Jr. / Wilson, Don E., and DeeAnn M. Reeder, eds. 2005. Order Cetacea. Mammal Species of the World: A Taxonomic and Geographic Reference, 3rd ed., vol. 1. 723-743
  19. Perrin, W. (2010). Mesoplodon peruvianus Reyes, Mead & Van Waerebeek, 1991. In: Perrin, W.F. World Cetacea Database. Accessed through: Perrin, W.F. World Cetacea Database on 2011-05-05
  20. Pitman, R. L. 2002. Mesoplodont whales Mesoplodon spp. In: W. F. Perrin, B. Wursig and J. G. M. Thewissen (eds), Encyclopedia of Marine Mammals, pp. 738-742. Academic Press.
  21. Pitman, R. L., Aguayo-L., A. and Urban-R., J. 1987. Observations of an unidentified beaked whale (Mesoplodon sp.) in the eastern tropical Pacific. Marine Mammal Science 3: 345-352.
  22. Pitman, R. L. and Lynn, M. S. 2001. Biological observations of an unidentified mesoplodont whale in the eastern tropical Pacific and probable identity: Mesoplodon peruvianus. Marine Mammal Science 17(3): 648-657.
  23. Reyes, J. C., Mead, J. G. and Van Waerebeek, K. 1991. A new species of beaked whale Mesoplodon peruvianus sp. n. (Cetacea: Ziphiidae) from Peru. Marine Mammal Science 7: 1-24.
  24. Rice, Dale W. 1998. Marine Mammals of the World: Systematics and Distribution. Special Publications of the Society for Marine Mammals, no. 4. ix + 231
  25. Sanino, G. P., Yáñez, J. L. and Van Waerebeek, K. 2007. A first confirmed specimen record in Chile, and sightings attributed to the lesser beaked whale Mesoplodon peruvianus Reyes, Mead and Van Waerebeek, 1991. Boletín del Museo Nacional de Historia Natural, Chile 56: 89-96.
  26. Scott, M. D., Hohn, A. A., Westgate, A. J., Nicolas, J. R., Whitaker, B. R. and Campbell, W. B. 2001. A note on the release and tracking of a rehabilitated pygmy sperm whale (Kogia breviceps). Journal of Cetacean Research and Management 3(1): 87-94.
  27. Texas A&M University - Corpus Christi, 2001. "Lesser beaked whale: *Mesoplodon peruvianus*" (On-line). Accessed November 17, 2001 .
  28. The Whale and Dolphin Conservation Society, 2001. "WDCS - The Whale and Dolphin Conservation Society" (On-line). Accessed November 17, 2001 at http://www.wdcs.org .
  29. UNESCO-IOC Register of Marine Organisms
  30. Urban-Ramirez, J. and Aurioles-Gamboa, D. 1992. First record of the pygmy beaked whale Mesoplodon peruvianus in the North Pacific. Marine Mammal Science 8: 420-425.
  31. Wang, J. Y. and Yang, S. C. 2006. Unusual cetacean stranding events of Taiwan in 2004 and 2005. Journal of Cetacean Research and Management 8: 283-292.
  32. Webb, J. Spring 1998. Scientist works to create portraits of whale and dolphin species. Smithsonian Institution Research Reports, 92.
  33. Wilson, Don E., and DeeAnn M. Reeder, eds. 1993. Mammal Species of the World: A Taxonomic and Geographic Reference, 2nd ed., 3rd printing. xviii + 1207
  34. Wilson, Don E., and F. Russell Cole. 2000. Common Names of Mammals of the World. xiv + 204
  35. World Biodiversity Database, 2001. "ETI - World Biodiversity Database" (On-line). Accessed November 15, 2001.

 

Glossary

Citation

Life, E. (2011). Peruvian beaked whale. Retrieved from http://www.eoearth.org/view/article/165911

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