Blainville's Beaked Whales, Mesoplodon densirostris
Taxonomy Animalia Chordata Mammalia Cetacea Hyperoodontidae Mesoplodon densirostris
Description & Behavior
Blainvilles's beaked whales, aka densebeaked whales, Mesoplodon densirostris (Blainville, 1817), measure 3-7 m in length. Their pectoral fin length is 20-70 cm, dorsal fin height is 15-20 cm, and the width of their tail flukes is about 100 cm. Color varies, but tends to be gray-brown on the dorsal (upper) side, lighter gray to white on the ventral (under) side. The bodies of these whales are often marked with scars and scratches, likely from competition among males for females using the 2 large teeth that protrude from the middle of the jaw. These teeth point up above the head and are often sheathed with a layer of barnacles. Additional teeth are non-functional. The mouths of females and juveniles are slightly upcurved. Blainville's beaked whales remain underwater for 10-40 minutes surfacing to breathe for just a few minutes before diving again. When they surface, they thrust the jaw and snout out of the water rocking the head back into the water as the dorsal fin surfaces.
Beaked Whales (Family Hyperoodontidae)
These medium-sized to moderately large whales have a single pair of grooves on the throat. There is a distinct snout, and often the few teeth present are visible only in adult males. They have a single nostril or blowhole. Beaked whales are generally slender with a small dorsal fin placed towards the rear on the back. The rear edge of the flukes usually lacks a well-defined notch. These whales are deep divers and are rarely seen. Many species are known only from a few specimens, and little is known about the life history and biology of the group. All members of this family, except Blainville's beaked whale, are difficult to distinguish from each other, and study by museum experts is usually necessary for identification.
World Range & Habitat
Blainvilles's beaked whale is found in both temperate and tropical waters. They are commonly found off the coast of Hawaii where they have been observed both in the water and washed ashore. They are found in deep waters, either alone or in small groups, where the ocean reaches depths of 1,000 fathoms. Because of their deep water habitat, for many years Blainville's beaked whales were only identified as a species by the presence of their skeletal remains.
Feeding Behavior (Ecology)
Blainville's beaked whales, M. densirostris, are thought to feed on deep water fish and squid.
What little we know of beaked whales has largely come from stranded animals. Sightings of these elusive creatures at sea are extremely rare due to their long dive times, deep habitat, and unobtrusive surfacing behavior.
Conservation Status & Comments
In order to protect beaked whales, we must determine their status. Visit the Center for Cetacean Research and Conservation (CCRC) to see what's being done.
References & Further Research
Jefferson, T.A., S. Leatherwood, and M.A. Webber, FAO species identification guide, Marine mammals of the world, Rome, FAO. 1993. 320 p. 587 figs.
Center for Cetacean Research and Conservation (CCRC) - Mesoplodon densirostris (+ videos)
Research Mesoplodon densirostris » Barcode of Life ~ BioOne ~ Biodiversity Heritage Library ~ CITES ~ Cornell Macaulay Library [audio / video] ~ Encyclopedia of Life (EOL) ~ ESA Online Journals ~ FishBase ~ Florida Museum of Natural History Ichthyology Department ~ GBIF ~ Google Scholar ~ ITIS ~ IUCN RedList (Threatened Status) ~ Marine Species Identification Portal ~ NCBI (PubMed, GenBank, etc.) ~ Ocean Biogeographic Information System ~ PLOS ~ SCIRIS ~ SIRIS ~ Tree of Life Web Project ~ UNEP-WCMC Species Database ~ WoRMS
Feedback & Citation
Have trouble with something? Let us know!
Help us continue to share the wonders of the ocean with the world, raise awareness of marine conservation issues and their solutions, and support marine conservation scientists and students involved in the marine life sciences. Join the MarineBio Conservation Society or make a donation today. We would like to sincerely thank all of our members, donors, and sponsors, we simply could not have achieved what we have without you and we look forward to doing even more.