Marine Mammal Jargon
Page by Wesley R. Elsberry. Created: 960620 Updated: 980731
As with any other field of study, marine mammals have a variety
of interesting terms that might be unfamiliar to the person
new to the field. This page aims to make some of those more
- An aromatic substance occasionally found in the
gastrointestinal tract of some great whales, formerly valued greatly
in the manufacture of perfumes.
- Sheets of stranded keratin arranged in overlapping sequence in
the mouths of Mysticetes for straining water. The "whalebone" of
18th and 19th century whalebone dresses; a single sheet of baleen
from a full-grown right whale could easily exceed 2 meters in length.
- The use of sound by animals to gain information about the
distance, shape, movement, or other properties of objects in their
environment. While research on captive animals has found that
biosonar in some species is a highly capable discrimination tool,
very little research has been done on how biosonar is actually
used in the wild. The simple presence of pulsed vocalizations
by cetaceans does not necessarily mean that biosonar is in use,
contrary to popular opinion.
- The external nares in cetaceans. Cetaceans are air-breathing
mammals, and when they surface, they tend to explosively exhale,
which is a "blow".
- The newborn or infant offspring of cetaceans or sirenians.
- A term that causes massive confusion in physics
students and others trying to get a grip on acoustics. A "decibel" is
not a unit; it is a ratio. As a ratio, each use of "decibel"
must be referenced to something. For most people, "decibel"
refers to the amplitude of a sound in air, which is a ratio of the
measured sound pressure level referenced to 0.000204 microbars.
For those dealing with underwater sound, "decibel" refers to the
ratio of a measured sound pressure level referenced to 1.0 micropascal.
These are not directly comparable measures.
- Dorsal fin
- An upward projecting fin on the dorsal side of many cetacean
species. Dorsal fin shape and trailing edge notch patterns may
be used for identification of individual animals.
- The use of biosonar for the purpose of determining distance
and relative direction of objects in the environment. Just as
pulsed vocalization does not necessarily mean that biosonar is
being used, so the use of biosonar does not necessarily mean that
echolocation is being done. Echolocation is a description of the
function of particular biosonar use. Very little work has
even approached documenting echolocation being done by wild
dolphins. There has been a great deal more speculation than
data collection in this regard.
- The broad, flat, horizontal structures at the posterior end of
cetaceans. These are cartilaginous, not bony. The flukes are moved
up and down to produce forward motion. Research is going on to
make catalogues of photos of great whales for individual identification,
since the patterns of notches and coloration on the flukes are highly
- A lek is a gathering place of a species, specifically for males
to display and attract females for breeding. Leks do not contain
significant food resources.
- Term for the taxon Mysticeti or any whale in that taxon; a mysticete
is a whale that has baleen instead of teeth. Mysticetes are filter
feeders, straining water through their baleen to capture prey items.
Mysticetes include the largest of the whales, the fin and blue whales.
The blue whale is the largest animal ever to have lived on earth.
- A toothed whale, as opposed to a Mysticete, or baleen whale. Dolphins,
porpoises, beaked whales, and sperm whales are all odontocetes.
- Pectoral fins
- The "flippers" of cetaceans. The pectoral fins are highly modified
- The part of the body of cetaceans posterior to the anus and to
which the flukes attach.
- Collective term for a group of whales. Many species of cetaceans
have apparent long-term associations as a group. Research is ongoing
as to the extent of pod cohesion over time.
- The newborn or infant offspring of pinnipeds.
- Common group name for the Balaenopterid whales (blue, fin, sei,
Bryde's, minke). Rorquals are fast-moving lunge-feeders with
relatively short baleen.
- The structure formed by the forward-projecting parts of the jaws in
some marine mammals. The "nose" of the bottlenose dolphin is actually
a rostrum. It really isn't a "nose" at all, since the nasal passages
don't come anywhere near it.