Algae - are a large and diverse group of plant-like organisms ranging from single solitary cells to multicellular forms; they only superficially resemble plants; alga = singular.
Alien Species - non-native species or non-indigenous species that are not orginally from the geographic area of interest; alien species are those species that are transported (usually by humans) to areas outside of their native home range.
Allele - any of the possible forms in which a gene for a specific trait can occur. In almost all animal cells, two alleles for each gene are inherited, one from each parent.
Atlantic - refering to or bordering the Atlantic Ocean which separates North and South America on the west from Europe and Africa on the east.
Ballast water - sea water that ships carry for stability and then discharge when their cargo is loaded; ballast water pumped into a ship contains larvae, microscopic organisms, and sometimes adult fishes or crabs.
Benthic zone - the ecological region at the bottom of a body of water such as a stream, lake or the ocean; the organisms living in the benthic zone are referred to as the benthos.
Biodiversity - diversity among and within plant and animal species in an environment; the variability among living organisms on earth.
Bryozoans - referred to as "moss animals", they are tiny colonial animals that generally build hard, stony skeletons of calcium carbonate; they superficially resemble coral.
Carapace – hard covering in crustaceans made of chitin, starting behind the head and covering the whole or part of the trunk; a dorsal section of an exoskeleton or shell in a number of animal groups.
Carnivore - an animal that eats other animals.
Catadromous species - species that reproduce in the ocean but spend most of their lives in freshwater (e.g. eels, Chinese mitten crabs).
Chitin (KAI-tin) - is a biological substance that is the main component of the cell walls of fungi (e.g. mushrooms), the exoskeletons of arthropods, such as crustaceans (like the crab, lobster and shrimp) and the insects (including ants and beetles), the radula of molluscs (like whelks and periwinkles), and the beaks of the cephalopods (like squid and octopi).
Chordates - a group of animals that includes the vertebrates together with several closely related invertebrates (namely, the sea squirts and lancelets); all chordates have, at some stage in their life cycle, four characteristics: a notochord, a dorsal hollow nerve cord, pharyngeal (gill) slits, and a post-anal tail. Interestingly, humans have all of these characteristics although some are only present when we are a developing fetus! For more information, please click here.
Cilia (SILL-ee-uh) - tiny hair-like or tail-like structures that are either used in movement, feeding (as in Bryozoans) or as sensory organelles.
Colonies - are aggregations of individuals of the same species that often benefit from existing as a group; examples of colonial organisms include corals and certain types of algae; sea squirts are often found growing in colonies because after one individual settles onto a hard substrate, it can reproduce asexually by budding.
Community – all the organisms that live in a particular area; an assemblage of populations of different species living close enough together for potential interaction.
Crustacean - Any of the various predominantly aquatic arthropods of the class Crustacea, including lobsters and crabs, characteristically having a segmented body, a chitinous exoskeleton, and paired jointed limbs.
Detritus - small pieces of dead and decomposing plants and animals.
Diatoms - a major group of algae; they are one of the most common types of phytoplankton; they are characterized by an encrusting cell wall made of silica.
Dorsally - of or pertaining to the back, usually the upward side of a fish; opposite of ventral.
Ecosystems - are natural units that consist of all plants, animals and microorganisms in an area interacting with one another and with all of the non-living physical factors of the environment; examples include: coral reef ecosystem, stream ecosystem, and marine ecosystem.
Elvers - pigmented glass eels; the elver stage lasts about three to twelve months.
Epiphyte (EPPY-fite) - an organism that grows upon or attached to a living plant of macrophyte/seaweed.
Estuary - the area where a freshwater stream or river merges with the ocean; also described as the tidal mouth of a river; estuaries are typically areas of high productivity.
Exoskeleton - an external feature that supports and protects an animal's body; exoskeletons are typically associated with the arthropods (e.g. insects, spiders and crustaceans).
Extirpate - to cause a local population to go extinct (diminish the numbers of individuals to zero).
Filter feeders - are animals that feed by straining suspended matter and food particles from water; they are also referred to as suspension feeders.
Food web - the interconnected food chains in an ecosystem; a series of organisms related by predator-prey and consumer-resource interactions.
Fouling/ship fouling - often referred to as biofouling, this is when a ship is encrusted with foreign matter such as barnacles or bryozoans.
Gastropods - more commonly known as snails, they are the most diversified class of molluscs with 60,000 to 75,000 known living species.
Gene - the basic physical unit of heredity.
Gene pool - all the genes, and their different alleles, present in an interbreeding population.
Genus - (plural = genera) is a low-level taxonomic rank used in the classification of organisms; a genus name is given to every species in a group of species which are closely related to one another.
Glass eels - as they enter coastal waters, leptocephali larvae metamorphose into transparent, tubular eels about 5-8 cms long; they begin to ascend rivers and have lost the leaf-like leptocephalus form.
Herbaceous - describes a plant that has leaves and stems that die at the end of the growing season; new growth forms from the roots or underground stems.
Herbivore - an animal that eats plant material.
Intertidal zone - the area along an ocean coastline that is exposed to air during low tide and submerged at high tide; organisms in the intertidal zone are adapted to harsh conditions (i.e. drying out, wave exposure, intense predation from intertidal foragers, and temperature fluctuations).
Invasive species - are often non-native species that rapidly colonize an area; successful introductions of invasive species usually results in the displacement, decline, or extinction of native species.
Invertebrate - an animal that lacks a vertebral column.
Larva - (plural = larvae) is the juvenile form of an animal; the larva can look completely different from the adult form; in many larvae of marine invertebrate species (e.g. snails or sea squirts) are planktonic.
Leptocephalus - the transparent ribbon- or leaf-like larvae with large teeth and a far-back anus in certain primitive fishes (American eels have a leptocephalus stage).
Lophophore (LOFF-uh-fore) - a feeding organ that comprises a ring of ciliated tentacles surrounding the mouth.
Molluscs - members of the very large and diverse phylum of invertebrate animals that includes such diverse groups as snails, clams, squid, cuttlefish and octopus.
Multicellular - multicellular organisms are organisms consisting of more than one cell, and having differentiated cells that perform specialized functions; most life that can be seen with the naked eye is multicellular.
Native species - species that orginate naturally from the geographic area of interest.
Non-indigenous species - species that did not originate naturally in the geographic area of interest.
Nudibranchs (NOO-dee-branks) - are commonly called "sea slugs", however, note that not all sea slugs are nudibranchs; nudibranchs are soft-bodied, shell-less marine heterobranch gastropod molluscs; they often have extraordinary colours and striking forms.
Oligotrophic - water that is relatively low in nutrients.
Omnivore – an animal that eats both plant and animal material.
Part per thousand (ppt) - this is a measure to describe the salinity of seawater; a part per thousand (ppt) is equal to one gram of salt in 1000 grams of water.
Perennial - a plant which lives for more than two growing seasons.
Planktonic - describes drifting organisms that inhabit the pelagic zone (upper layers) of marine or fresh bodies of water; Greek word "planktos" means wanderer or drifter.
Polychaetes - The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin.
Population - a group of organisms of the same species inhabiting a given area.
Rhizomes - A root-like stem which is prostrate, grows partly or wholly underground, and can root from the stem nodes.
Subtidal - A marine or estuarine environment that lies below mean low-water; always (or almost always) submerged in a tidally-influenced area.
Species - a group of organisms capable of interbreeding and producing fertile offspring.
Seaweed - any of a large number of marine plants in the category of benthic algae. They are macroscopic and multicellular, in contrast with most other algae.
Sea slugs - a very large group of gastropod molluscs, which includes such groups as the nudibranchs and sea hares.
Siphons - tubular openings that look like chimneys that are used as the filter-feeding structures for many marine animals (eg sea squirts).
Stamens - The male reproductive organ of the flower producing pollen.
Turbid - clouded as with sediment; "a cloudy liquid"; "murky waters".
Ventral - the front or bottom side of an animal.
Zooids - individual bryozoans occurring within a colony.