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Polyp

body form characterized by a fixed base, bag-like body, and oral/anal opening at the top surrounded by a ring of tentacles; corals, sea anemones and juvenile medusa jellies have a polyp form; may produce clone polyps by budding

Porifera

sponge phylum

Posterior

toward the tail end or rear

Potency

strength

Precautionary principle

Where there are threats of serious or irreversible damage to the environment, lack of full scientific certainty should not be used as a reason for postponing cost-effective measures to prevent environmental degradation. Permits use of a lower level proof of harm in policy-making whenever the consequences of waiting for higher levels of proof may be very costly and/or irreversible.

Precocial

animals in which the young are born well developed and require little to no parental care

Predation

act of capturing prey for food

Predator

animal that captures and consumes other animals

Prehensile

adapted for grasping or holding

Prenatal

preceding birth

Prey

animal hunted or killed for food by another animal

Primary producer

organism that makes own food by photosynthesis and/or chemical energy and is basis of a food chain

Proboscis

elongated or protruding organ or tube-like structure located in the oral region of many animals and commonly used in feeding; in pinnepeds an enlargement of the nose

Producer

organism that produces its own food through photosynthesis

Purse seine

a type of fishing net with an open end which can be drawn up to form a bag shape to capture the fish

Purse seine

a type of fishing net with an open end which can be drawn up to form a bag shape to capture the fish

Quadrupedal

four-footed animal

Radial symmetry

symmetrical arrangement of an animal's body around a central axis

Radula

tongue-like band of teeth used by many mollusks to scrape, tear or bore

Raft

large number of animals together in the water; usually applied to birds and pinnepeds

Rasp

to scrape or rub as with a file

Recruitment

process whereby young organisms are added to an adult population

Red tide

concentrations of certain microscopic organisms, particularly dinoflagellates, that discolor surface waters, usually in coastal regions and reduce oxygen supplies to animals deeper in the water column; some may be toxic

Regeneration

ability of some organisms to renew or replace an injured or lost organ or body part

Regurgitation

casting up of incompletely digested food, usually for the feeding of young

Reptile

vertebrate animal characterized as cold-blooded and having scales

Respiration

breathing; the act of assimilating oxygen and releasing carbon dioxide and other products

Rhizomes

horizontal plants capable of producing the upward shoot and downward root of a new plant

Rhopalia

concentration of neurons and sensory organs around a jelly's bell and between lobes; contains statocysts and ocelli

Rostrum

in fish - forward projection of snout; in cetaceans - upper jaw forming part of snout or beak; in crustaceans - forward pointing spine on the carapace

Rufous

reddish; tinged with red; brownish-red

Salmonid

fish belonging to the family Salmonidae which includes salmon, trout, char, whitefish, and graylings

Salt pan

small dip in high meadows where water is stranded after the tide falls

Saltmarsh

transition area of salt tolerant plants between terrestrial and marine ecosystems that are occasionally flooded by high tides; high marsh in contrast to low marsh mudflat

Sargassum

species of brown algae that is primarily found in the Sargasso Sea

Scavenger

animal that feeds on dead plants and animals

Scrape

depression in the sand or substrate that some shorebirds birds create. The bird leans forward on its breast and scratches with its feet while rotating its body axis.

SCUBA

device that lets a diver breathe air while under water (letters stand for Self-Contained Underwater Breathing Apparatus

Scyphozoa

class of Cniderians that includes jellies with a medusa form; true jellies

Sea

subdivision of the ocean, a smaller and shallower body of water than the ocean; often semi-enclosed or marginal where between land and the ocean

Sea ice

ice inpolar egions that has formed from salt waterthat has formed from salt water

Seagrass

collective name for vascular marine flowering plants that grow in shallow waters on soft substrate

Seamount

peaked, underwater mountain rising at least 1,000m (3,280ft) above the ocean floor

Seaweed

collective name for non-vascular, non-microscopic plants that usually contain chlorophyll; commonly called algae

Secondary consumers

carnivorous animals

Sedentary

remaining in one place

Semi-altricial

developmental pattern of young birds in which the young are relatively immobile when they hatch, and are fed by the adults, but the young at birth are down-covered rather than naked.

Semidiurnal tide

tide that has two high and two low waters in each tidal day

Semiprecocial

chicks hatch with eyes open, covered with down, and able to walk; but unlike fully precocial chicks, remain in or near the nest for several weeks

Sessile

permanently attached to a substrate