adult: Sexually mature, at or near full size.

anterior: Located on or near the front of the animal's body

baleen/baleen plates: Triangular plates made of keratin; having a

fibrous, hairy fringe on the inner edge. Several hundred of these plates hang from the roof of a baleen whale's mouth, helping to strain food from the water.

baleen whale: One of 11 species of whales having baleen plates

"bait ball": describing the defensive schooling behavior of

some bait fish as large numbers tighten into a dense oval (when approached by predators like whales, sharks and billfish).

beak: Jaws of a cetacean which project forward from the head.

blow: Exhaled cloud of moisture from cetacean. The act of breathing.

blowhole: Nostrils on head.

blubber: Layer of fat below the skin, which helps insulate cetaceans and

many other marine mammals.

bow: Front of the boat

bow-riding: Surfing on the pressure wave created in front of a moving ship

or large whale.

breaching: Full body or partial body leaps out of the water resulting in a

large splash.

calf: A baby cetacean still being feed milk by mother.

caudal: Of, at or near the tail.

carpals: Bones of the wrist.

cervical: Of the neck

cetacean: Marine mammals belonging to the order Cetacea, which includes

all whales, dolphins and porpoises (currently 79 species).

clavical: collarbone, links the sternum and the scapula.

clicks: loud impulsive sounds emitted by sperm whales; repeated at slow

and very regular intervals.

cookie-cutter shark: A group of tiny sharks which feed by taking small

round plugs of flesh from the body of cetaceans and other types of larger predators.

cow: Adult female whale.

crow's nest: A small lookout platform with a protective railing located near

the top of a ship's mast.

distal sac: A passageway linking the right and left nasal passages in the

head of sperm whales.

dolphin: Smaller cetaceans with conical teeth and usually a pointed dorsal

fin contained in several families within the order Cetacea.

dorsal: Of, toward, on, in or near the back.

dorsal fin: The main fin on the dorsal surface of certain marine mammals

and fishes.

dorsal ridge: hump or ridge on the dorsal surface of some cetaceans in

place of a prominent dorsal fin.

echolocation: Sound emission by cetaceans, who "read" the returning echo

to navigate and find food.

falcate: Curved, sickle-shaped.

flipper: Fore-limb of a cetacean, also called the "pectoral fin"

flipper-slapping: Lifting a flipper out of the water and slapping it on the

surface.

fluke: One of two horizontally flattened sections of the tail of a cetacean, containing no bone.

fluking: Raising of tail out of water as a whale dives.

genital slit: External opening to a cetacean's internal reproductive and

urinary tracts.

herd: Group of cetaceans usually asociated with baleen whales

humerus: The long bone of the upper portion of the fore limb.

hydrophone: An electrical instrument for detecting or monitoring sound

underwater.

junk: A material found below the spermaceti organ in a sperm whale's head.

juvenile: A young animal, weaned from its mother, but not yet sexually

mature.

keel: Distinctive bulge on the tail stock, near the flukes.

keratin: A tough, fibrous protein forming structures such as hair, nails,

horns, hooves and baleen.

leviathan: A monstrous sea creature mentioned in the Old Testiment. Job

41:1

lobtailing: Slapping the flukes with great force on the water.

lumbar: Region of the back between the ribs and pelvis.

mammals: A class of warm-blooded vertebrates (backboned animals)

including humans and cetaceans in which the females produce milk

from mammae.

mamma: An organ of female mammals that contains milk-producing glands.

mandible: The lower jaw.

maxilla: One of a pair of bones forming the upper jaw.

melon: Rounded forehead of many toothed-whales, dolphins and porpoises.

metacarpals: Bones of the hand or foot between the phalanges (finger or toe

bones) and carpals (wrist).

notch: Indentation on tail where trailing edges of two flukes meet.

phalanges: Bones of fingers or toes.

pod: Group of cetaceans, often used with larger toothed whales.

porpoising: Leaping out of the water while speeding forward.

port: Left side of a boat.

posterior: Pertaining to the caudal end of the body in an animal.

radius: One of two bones found in the forearm.

ridge: Raised line(s) on the rostrum of some cetaceans running longitudinally

between blowhole and snout.

rorqual: A group of baleen whales which include the blue, fin, sei, brydes,

minke and humpback whales.

rostrum: The forward extension of the upper jaw of the skull.

saddle patch: Light patch of pigment behind the dorsal fin on some

cetaceans.

sexual dimorphism: Size and shape differences between male and females

of the same species.

sloughed skin: A piece of skin which is shed from the body.

spermaceti: A waxy substance found in the head of the sperm whale.

spermaceti organ: Structure in head of sperm whale containing spermaceti.

sperm whale acoustics:

regular clicks: Long sequences of loud sound pulses at rates typically between one and two per second.

Frequency ranges between 100 Hz to over 30 kHz. Loudness at source as high as 180 dB.

creaks: Rapid sequences of clicks, produced at rates of up to 220 per second and lasting for 10-25 seconds. They are thought to be made by sperm whales when investigating food sources.

rapid clicks: Sequence of clicks at rates of 80 per second, sometimes heard from sperm whales at the surface when investigating an object.

clangs: Very loud slow clicks about one every 7 seconds. Have been associated with large male sperm whales at or near the surface.

codas: Distinctive and sterotyped patterns of clicks. Most often heard at the end of regular clicks from larger groups of socialising whales at the surface. The purpose of codas is unknown, but may have a role in acoustic communication.

spyhopping: Raising the head vertically out of the water, possibly to view

surroundings.

squid: A variety of marine invertebrates (Cephalopods) with an elongated

body and ten arms surrounding a mouth. Primary food for many cetaceans.

starboard: The right side of a boat.

stern: The back of a boat.

sternum: Breastbone.

tail stock: Region from behind dorsal fin to the flukes. Also called the

"caudal peduncle".

throat grooves: Folds of skin that run from underneath the lower jaw to

just behind the flippers in some cetaceans (particularly the rorquals).

toothed whale: Suborder of cetaceans with teeth (Odontoceti).

ulna: One of two bones of the forearm.

ventral: Pertaining to the belly or abdominal region of an animal.

vertebrae: Bones forming the spinal column.

vocalizations: Sounds emitted by cetaceans that may be of a communicative

nature.

weaned: No longer taking milk from its mother.

whale: A general term used to describe any large cetacean and several

smaller ones.

whale-watching: A activity in which humans look for and possibly view

whales in the natural habitats.

whaling: The activity in which humans hunt and kill whales for meat,

blubber and other products.

whistles: Higher frequency sounds emitted by many cetaceans.

white caps: A wave with a crest of foam.