Texas Marine Mammal Stranding Network

Dedicated to the conservation of marine mammals through rescue and rehabilitation, research and education.



A ^

Adult: Sexually mature animal that is (or is almost) fully grown.

Ambergris: A waxy, grayish substance formed in the intestines of sperm whales and sometimes found floating at sea or washed ashore. Used as a fixative in perfumes.

Amphipod: Shrimp-like crustacean that is a food source for some whales.

Anchor Patch: Variable gray-white anchor or W-shaped patch on the chests of some small toothed whales.

Antarctic Convergence: Natural boundary in the oceans around Antarctica, where cold waters from the south sink below warmer waters from the north; lying roughly between 50 degrees to 60 degrees S, it shifts slightly with the seasons.

Anterior: Situated at or near the head.

B ^

Baleen/baleen plate: Comb-like plates hanging from the upper jaw of many large whales, used to strain small prey from seawater (also known as "whalebone").

Baleen Whale: Suborder of whales with baleen plates instead of teeth; scientific term Mysticeti, from Greek mystax, meaning "mustache," and cetus, meaning "whale".

Beach-Rubbing: Rubbing the body on stones in shallow water near the shore.

Beak: Forward-projecting jaws of a cetacean (also known as "snout").

Benthic: Relating to the bottom of the sea.

Biota: The animal and plant life of a region considered as a total ecological entity.

Blaze: Light streaking of color, usually starting below the dorsal fin and pointing up into the cape.

Blow: Cloud of moisture-laden air exhaled by cetaceans (also known as "spout"); may be used to describe the act of breathing.

Blowhole: Nostril(s) on the top of the head.

Blubber: Insulating layer of fat beneath the skin of most marine mammals.

Bow-Riding: Riding on the pressure wave in front of a ship or large whale.

Breaching: Act of leaping completely out of the water (or almost completely) and landing back with a splash.

Bull: Adult male whale.

C ^

Calf: Baby cetacean that is still being nursed by its mother.

Callosities: Fleshy wart-like growths from skin of some whales.

Callosity: Area of roughened skin or horny growth on the head of a right whale.

Cape: Darker region on the back of many cetaceans around the dorsal fin.

Cetacean: Marine mammal belonging to the order Cetacea, which includes all whales, dolphins, and porpoises.

Chevron: V-shaped stripes.

Circumpolar: Ranging around either pole.

Coastal: Adjacent to ocean shores.

Continental Shelf: Area of sea floor adjacent to a continent, sloping gently to a depth of about 655 feet (200 m); beyond the shelf edge, the sea floor drops steeply (via the continental slope) to the ocean bottom.

Copepod: Small crustacean in the class Copepoda.

Cow: Adult female whale.

D ^

Depleted Status: Species whose numbers are below its optimal sustainable population level.

Dimorphism: Two different forms of traits. Sexual dimorphism: traits differ between sexes.

Dive pattern: Typical behavior and timing of a whale's blow and dives.

Dolphin: Relatively small cetacean in any of several different families, with conical-shaped teeth and (usually) a falcate dorsal fin; as a general term, may be used interchangeably with "porpoise".

Dorsal: Toward the upper side.

Dorsal fin: Raised structure on the back of most cetaceans.

Dorsal Ridge: Hump or ridge that replaces a dorsal fin in some cetaceans.

E ^

Echolocation: System used by many cetaceans to orientate, navigate, and find food by sending out sounds and interpreting the returning echoes.

Endangered Status: Species in danger of extinction in all or significant portion of its range, as defined by the Endangered Species Act.

Euphausiid: Small shrimp-like crustacean in the order Euphausiacea. Also called krill.

F ^

Falcate: Sickle-shaped and curved backward.

Flipper: Paddle-shaped front limb of a cetacean (sometimes known as "pectoral fin").

Flipper-Slapping: Raising a flipper out of the water and slapping it onto the surface.

Flukes: Horizontally flattened tail of cetaceans (containing no bone).

Fluking: Act of raising the flukes into the air upon diving.

G ^

Gestation: The carrying of young in the uterus until birth.

Gregarious: Social.

Gum Teeth: Horny protuberances on the gums of Dall's Porpoise, forming a tough ridge between the real teeth.

H ^

Herd: Coordinated group of cetaceans; term often used in connection with larger baleen whales.

J ^

Juvenile: Young cetacean that is no longer being nursed by its mother but is not yet sexually mature.

K ^

Keel: Distinctive bulge on the tail stock near the flukes; it can be on the upper side, underside, or both.

Krill: Small, shrimp-like crustaceans that form the major food of many baleen whales. There are more than 80 species.

L ^

Lactation: Production of milk by female; duration of suckling.

Lobtailing: Forceful slapping of the flukes against the water while most of the animal lies just under the surface. Also known as "tail-slapping".

Locally Common: Uncommon or absent over most of range, but relatively common in one or more specific localities.

Logging: Lying still at or near the surface.

M ^

Melon: Bulbous forehead of many toothed whales, dolphins, and porpoises; believed to be used to focus sounds for echolocation.

Migration: Regular journeys of animals between one region and another, usually associated with seasonal climatic changes or breeding and feeding cycles.

Mysticeti: See Baleen Whale.

N ^

Neritic: Pertaining to the near-shore, shallow-water zone of a sea over the continental shelf.

O ^

Oceanic: Anywhere in the ocean beyond the edge of the continental shelf, usually where the water is deeper than 655 ft (200m).

Odontoceti: See Toothed Whale.

P ^

Pack Ice: Mass of floating pieces of ice driven together to form a solid layer.

Pantropical: Occurring globally between the tropics of Cancer and Capricorn.

Parasite: Organism that benefits from another organisms while harming it.

Pectoral Fin: See Flipper.

Peduncle-Slapping: Act of throwing the rear portion of the body out of the water and slapping it sideways onto the surface, or on top of another whale (also known as "tail-breaching").

Pelagic: Living in the upper waters of the open sea far from land.

Permanent Ice: Core areas of ice around both poles; this ice does not melt, but is surrounded by outer zones of ice that form each autumn and disperse each spring.

Pod: Coordinated group of cetaceans; term often used in connection with larger toothed whales.

Polar: Of the areas around the poles.

Polygynous: One male mates with more than one female.

Population: Group of animals of the same species that is isolated from other such groups and interbreeds.

Porpoise: Small cetacean in the family Phocoenidae, with an indistinct beak or no beak, a stocky body, and spade-shaped teeth; most have a triangular dorsal fin; as a general term, may be used interchangeably with "dolphin".

Porpoising: Leaping out of the water while moving forward at speed.

Posterior: Situated at or near the tail.

Purse-Seining: Fishing with a long net - up to 1¼ miles (2 km) in length and 330 feet (100 m) deep - that is set around a shoal of fish to form a circular wall, then gathered at the bottom and drawn in to form a "purse".

R ^

Race: Interbreeding group of animals that is genetically distinct from other such groups of the same species; races are usually geographically isolated from one another.

Range: Natural distribution of a species, including migratory pathways and seasonal haunts.

Resident: Stays in one area all year round.

Rooster Tail: Spray of water formed when certain small cetaceans surface at high speed; it is caused by a cone of water coming off the animal's head.

Rorqual: Strictly speaking, a baleen whale of the genus Balaenoptera; however, many experts also include the Humpback Whale (genus Megaptera) in this group.

Rostrum: Upper jaw of the skull (may be used to refer to the beak or snout).

S ^

Saddle Patch: Light patch behind the dorsal fin on some cetaceans.

School: Coordinated group of cetaceans; term often used for dolphins.

Seamount: Isolated undersea mountain (usually a volcano) with the summit lying well below the ocean surface.

Sexual maturity: Age at which animal is first capable of breeding.

Snout: See Beak.

Sonar: System used by many cetaceans to echolocate.

Sounding Dive: Deep (and usually longer) dive after a series of shallow dives (also known as "terminal dive").

Species: Group of similar animals, reproductively isolated from all other such groups and able to breed and produce viable offspring.

Splashguard: Elevated area in front of the blowholes of many large whales, which prevents water from pouring in during respirations (also known as "blowhole crest").

Spout: See Blow.

Spyhopping: Raising the head vertically out of water, then sinking below the surface without much splash.

Stranding: Act of a cetacean coming onto land, either alive or dead; mass stranding involves a group of 3 or more animals.

Submarine Canyon: Deep, steep-sided valley in the continental shelf.

Subspecies: Recognizable subpopulations of a species, typically with a distinct geographical distribution.

T ^

Tail Stock: Region from just behind the dorsal fin to the flukes (also called "peduncle" or "caudal peduncle").

Taxonomy: Classification of organisms according to how they are related to one another.

Temperate: Mid-latitude regions between the tropics and the polar circles, with a mild, seasonally changing climate; cold temperate regions are toward the poles, warm temperate regions are nearer the tropics.

Threatened Status: Species likely to become endangered within foreseeable future in all or significant part of its range.

Throat Grooves: Grooves on the throat present in some groups of whales.

Toothed Whale: Suborder of cetaceans with teeth; scientific term Odontoceti, from the Greek odous, meaning "tooth," and cetus, meaning "whale".

Transient: Always on the move rather than staying in one area; usually refers to Killer Whales.

Tropical: Pertaining to low latitudes of the world between the tropic of Cancer and Capricorn.

Tubercles: Circular bumps along the edges of the flippers and dorsal fins of some cetaceans; also the knobs on a Humpback Whale's head.

V ^

Ventral: Relating to the underside.

Ventral grooves: In certain baleen whales, the furrows extending back from the chin.

Vestigial: Pertaining to part of an animal that is in the process of being evolutionarily lost and is small, imperfectly formed, and serves no function.

W ^

Wake-Riding: Swimming in the frothy wake of a boat or ship.

West-Wind Drift: Principal circumpolar current around Antarctica, flowing in an easterly direction.

Whale: General name applied to any large cetacean and a specific name applied to certain smaller ones.

Whale Lice: Small, crablike parasites that live on some species of whale.

Whaling: The intentional hunting and killing of whales for their meat, blubber, baleen, and other products.

Z ^

Zooplankton: Minute animals adrift in water column, including early life stages of fish and invertebrates.

Source of information:
Carwardine, Mark. Eyewitness Handbook Whales, Dolphins, and Porpoises. 1995.
Leatherwood, Stephen and Randall R. Reeves. The Sierra Club Handbook of Whales and Dolphins. 1983.
Wynne, Kate and Malia Schwartz. A Guide To Marine Mammals Turtles of the U.S. Atlantic Gulf of Mexico. 1999.