Hubbs' beaked whale (''Mesoplodon carlhubbsi'') was initially thought to be an

Andrews' beaked whale Andrews' beaked whale (''Mesoplodon bowdoini''), sometimes known as the deep-crest beaked whale or splay-toothed whale, is one of the least known members of a poorly known genus. The species has never been observed in the wild, and is known only ...

when discovered by

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Carl Hubbs; however, it was named in his honor when it was discovered to be a new species. This species has the typical dentition found in the genus, but its main outstanding features are a white "cap" on the head and very extensive scarring. The species is known from 31 strandings, a few at-sea sightings, and observations of two stranded whales that were kept in captivity for 16-25 days.

Taxonomy

Carl Leavitt Hubbs Carl Leavitt Hubbs (October 19, 1894 – June 30, 1979) was an American ichthyologist. Biography Youth He was born in Williams, Arizona. He was the son of Charles Leavitt and Elizabeth (née Goss) Hubbs. His father had a wide variety of jobs (f ...

, a noted American ichthyologist, published a description of a whale found alive in the surf near his office at the

Scripps Institution of Oceanography The Scripps Institution of Oceanography (sometimes referred to as SIO, Scripps Oceanography, or Scripps) in San Diego, California, US founded in 1903, is one of the oldest and largest centers for oceanography, ocean and Earth science research ...

La Jolla La Jolla ( , ) is a hilly, seaside neighborhood within the city of San Diego, California, United States, occupying of curving coastline along the Pacific Ocean. The population reported in the 2010 census was 46,781. La Jolla is surrounded on ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, in 1945. He believed it to be

(a very similar species found only in the Southern Hemisphere), but Joseph Curtis Moore, an expert on beaked whales at Chicago's

Field Museum The Field Museum of Natural History (FMNH), also known as The Field Museum, is a natural history museum in Chicago, Illinois, and is one of the largest such museums in the world. The museum is popular for the size and quality of its educational ...

, reassigned it to a new species, ''Mesoplodon carlhubbsi'', in 1963, naming it in his honor.Reeves et al. (2002), ''Guide to the Marine Mammals of the World'', p. 288.

Description

Hubbs’ beaked whale ''M. carlhubbsi'' has a light ventral surface and a midventral portion grading from white to medium gray dorsally. The dorsal surface of the flipper is slightly darker than the adjacent thorax in adult females, with a faint light patch on the distal posterior edge. However, the light patch is more noticeable in adult males. The head of adult male ''M. carlshubbsi'' is the most striking feature- black with naturally white areas on the tip of the rostrum and anterior to the blowhole. For females, the tip of the rostrum is distinctly lighter than the rest of the head. Males also have a strong pair of teeth protruding from the mandibular symphysis.

Population and distribution

It is estimated ''M. carlhubbsi'' are along the coast of Japan and Pacific coast of North America. The distribution along North America extends from San Diego to Prince Rupert. Southern limit is unknown but the northern limit is Vancouver Island. Distribution is probably not directly related to the character of the water mass but rather follows the distribution of the prey species it feeds on. M. carlshubbi follows prey items in intermediate and deep-water masses, rather than surface water masses.

Behavior

Stomach contents of stranded ''M. carlhubbsi'' contained squid beaks, fish otoliths, and fish bones. Prey species included

Gonatus ''Gonatus'' is a genus of squid in the family Gonatidae, comprising twelve species, and therefore containing the most species in the family. Adult squid belonging to species in this genus are notable for their lack of tentacles. The genus contai ...

sp.,

Chauliodus macouni The Pacific viperfish, ''Chauliodus macouni'', is a predatory deep-sea fish found in the North Pacific. It is reported as being either mesopelagic or bathypelagic, with diel vertical migration to shallower waters. The Pacific viperfish is one o ...

Icichthys lockingtoni ''Icichthys lockingtoni'', commonly known as the medusafish, is a species of medusafish native to the northern Pacific Ocean, where it ranges from Japan and the Gulf of Alaska to central Baja California in Mexico. It typically occurs at a depth of ...

, and

Poromitra crassiceps ''Poromitra crassiceps'', commonly called the crested bigscale (also called large-headed midnight fish, crested melamphid, or one-horned melamphaid) is a species of deep sea fish in the ridgehead family. While the fish with the common name cres ...

. Researchers assume calving takes place in the summer based on lengths of neonatal specimens, gestational period, and fetal growth in most cetaceans. On October 3 they found a 90 cm fetus which had about 160 cm of growth before birth which gives an estimated time of birth of about mid-May. A few acoustic and other behavioral observations were made of stranded ''M. carlhubbsi'' when they were held briefly in captivity. A stereotyped beaked whale echolocation pulse type (termed BW37V) is thought to be made by this species but has not been linked to a sighting, so this attribution is considered provisional.

Conservation

The species has been occasionally killed by Japanese whalers and has been caught in driftnets off California. Recent strandings in Hawaii have occurred, supporting the theory of open ocean habitation by this species. Threats include fishing and harvesting of aquatic resources, pollution, and climate change. ''M. carlhubbsi'' are occasionally taken by Japanese whalers and small cetacean fisheries. Incidental catches in drift gillnets occur sporadically off the coast of California. Climate change and severe weather may cause ''M. carlhubbsi'' to shift habitat. Also, as with most beaked whales, they may be vulnerable to loud anthropogenic sounds, especially those generated by navy sonar and seismic exploration.

References

Animal diversity web https://animaldiversity.org/accounts/Mesoplodon_carlhubbsi/ Whale and dolphin conservation https://us.whales.org/whales-dolphins/species-guide/hubbs-beaked-whale/ NOAA Olympic Coast National Marine Sanctuary https://olympiccoast.noaa.gov/living/marinelife/mammals/specieslist/spp_hubbsbeaked.html IUCN Database https://www.iucnredlist.org

Bibliography

Griffiths, E.T., Keating, J.L., Barlow, J. and Moore, J.E. 2019. Description of a new beaked whale echolocation pulse type in the California Current. Marine Mammal Science 35: 1058–1069 Mead, J.G., W.A. Walker, and W.J. Houck. Biological observations on ''Mesoplodon carlhubbsi'' (Cetacea: Ziphiidae). Smithsonian Contributions to Zoology. 344 Lynn, S. K. and D. L. Reiss. 1992. Pulse sequence and whistle production by two captive beaked whales, ''Mesoplodon'' species. Marine Mammal Science 8:299–305 Taylor, B.L., R. Baird, J. Barlow, S.M. Dawson, J. Ford, J.G. Mead, G. Notarbartolo di Sciara, P. Wade, and R.L. Pitman. 2008. Mesoplodon carlhubbsi. The IUCN Red List of Threatened Species. Available from https://www.iucnredlist.org/species/13243/3425482

External links

Cetaceans of the WorldWhale & Dolphin Conservation Society (WDCS)
{{DEFAULTSORT:Hubbs' Beaked Whale Mesoplodont whales Mammals described in 1963