pertaining to the abyssal zone (2000-6000 meters depth).
abyssal plains
a flat, almost level area occupying the deepest parts of many of the ocean basins at a depth of 10,000 - 20,000 ft (3,000 - 6,000 m).
animal-mounted instrumentation
instrumentation for the purpose of sampling or sensing environmental conditions that are deployed as part of a satellite telemetry tracking tag or by being attached in some way to an animal.
apex predator
Apex predators (also alpha predators, superpredators, or top-level predators) are predators that, as adults, are not normally preyed upon in the wild. These species are usually the top of the food chain and play a crucial part in determining the health of their ecosystem.
any member of the phylum Arthropoda, the largest phylum of animals. These organism are characterized by having a jointed or segmented body covered by a chitinous exoskeleton. This phylum includes insects, crustaceans, arachnids, and others.
scientists specializing in the field of astrobiology, which is the study of life in space. These scientist combine the fields of astronomy, biology, and geology to study the origin, distribution, and evolution of life not just on our planet, but, perhaps, on others as well.
autonomous baited landers
an oceanographic research tool that is essentially a weighted frame which supports a host of scientific instruments, cameras, etc that is lowered into the sea. These landers are placed in study areas and are left to record data, take photographs etc for a time period before being later recovered. In some cases these landers are baited in order to attract sea life for photography or video purposes.


a common gray to black volcanic rock that forms the predominant component of oceanic tectonic plates.
of or associated with the bathyal zone of the ocean. This zone is characterized by depths between 1000 and 4000 meters below the sea's surface.
a flat elasmobranch fish, e.g. skate or ray, with the pectoral fins fused to the sides of the head and the gill openings on the ventral surface. This terms describes more than 500 species from 13 families and includes: stingrays, skates, guitarfishes, and sawfishes.
of or associated with the bottom or floor of a body of water. Benthic organisms spend the majority of their life cycle close to, on or in the sea-floor.
the total variation of life in a given ecosystem. This term may also be used to describe a measurement of that total variation within the ecosystem in question. Most often this describes the number of individual species within a given system or range.
the study of the distribution of life over space and time. This science looks specifically at where species live, at what abundance, and why, as well has how this may change over time.
any mollusk belonging to the class Bivalvia. These organisms are typified by having two-part shells that are symmetrical and enclose or partially enclose the living animal. This class has at least 30,000 species including clams, scallops, mussels, and oysters.
bottom trawls
a fishing or collecting method that involved the towing of closed-ended nets along the seafloor behind a vessel.
box cores
a scientific sampling device usually deployed from manned submersibles that consists of a hollow box-type structure that is lowered or forced into the seafloor sediments. A closure system is then triggered that encloses the sediments within the box allowing scientists to collect a core of sediment including its interstitial water and organisms.


carbonate chimney
a type of undersea geologic feature that forms when high pH fluids carrying calcium react with lower pH seawater. Calcium carbonate precipitates out of the resulting mix and deposits to form spire or tower shaped formations.
term used to describe members of the Class Chondrichthyes. These fish have skeletons made from a tissue called cartilage as opposed to bone. Cartilage is a strong, flexible tissue that is composed of collagen and/or elastin fibers.
any organism that uses energy derived from chemical reactions to synthesize all necessary organic compounds from carbon dioxide. These organisms are the primary producers in environments such as hydrothermal vents, cold seeps and other similar ecosystems where light is absent and photosynthetic producers cannot survive.
the biological conversion of carbon dioxide or methane into organic matter using energy derived from the oxidation of inorganic molecules. This process is used by chemoautotrophic organisms that are responsible for the primary production in oxygen deficient environments where photosynthesis cannot occur.
chemosynthetic bacteria
any group of bacteria that are chemoautotrophic.
any member of the Phylum Cnidaria, characterized by a radially symmetrical body and microscopic stinging cells called nematocysts, includes jellyfish, corals and anemonmes.
a type of fish characterized by lobed, fleshy fins. The group was thought to be extinct until the currently known species was found in the Indian Ocean in 1938.
colonization pathway
a biogeography concept which describes the physical movements of a group of organisms as they expand their range.
commercially extinct
when a population becomes too small for continued commercial exploitation.
an arthopod of the class Crustacea characterized by a segmented body, an exoskeleton made of chitin, and paired jointed limbs, includes crabs, lobsters, shrimp and barnacles.
any member of the phylum Ctenophora, a gelatinous invertebrate characterized by having eight rows of comblike cilia used for swimming, also known as comb jellies.
a photosynthetic bacterium that in some cases is able to fix nitrogen. The majority of the oxygen in the atmosphere is thought to have resulted from the emergence of cyanobacteria. Used to be called blue-green algae.
an order of Ctenophores that are round or oblong, about one inch across, and are characterized by having two usually branched tentacles for catching planktonic prey.


having ten legs or extensions; can be crustaceans such as lobsters or mollusks such as squid.
deep-towed video
an instrument used for underwater viewing where a camera equipped vehicle is towed behind a research vessel to record or broadcast video of the sea floor or water column at various depths.
living, found near, or deposited on the bottom of a body of water. A common descriptor of plankton and fish larvae.


the interactions between a community of organisms and the physical environment.
any member of the class Chondricthyes, characterized by a cartilaginous skeleton and placoid scales, includes sharks, skates and rays.
the very early stages of an organism in development.
a partially enclosed body of water where freshwater meets saltwater.
still in existence, the opposite of extinct.
originating or existing outside the Earth's atmosphere.


thin in diameter, resembling a thread. Pertains to types of algae.
see "filamentous".
fracture zone
a long narrow rift on the ocean floor, separating areas of differing depth.


gene flow
transfer of genes from one population to another of the same species, can occur via migration or dispersal of seeds and pollen.
ghost shrimp
a crustacean found off the Pacific coast of North America with a pinkish, transparent body.
a deep sea fish with a long tapering tail, large head and large body. Also known as a rattail.


the feeding zooid in a hydroid colony, characterized by having an oral opening surrounded by tentacles.
the hollow stem of a hydroid, can be either simple or branched in structure.
relating to the forces and motions of liquids.
a colorless, poisonous gas that smells like rotten eggs. Formed by decaying organic matter, such as in salt marshes.
any of various characteristically colonial hydrozoans having a polyp rather than a medusoid dominant life stage.
hydrothermal vent
a fissure in the deep ocean floor out of which flows water that has been heated by the liquid magma below the earth's crust. Vents create a unique ecosystem for various forms of marine life, many using chemosynthetic processes.


ICES (International Council for the Exploration of the Sea)
an organization that promotes marine research in the North Atlantic and adjacent seas. Includes over 1600 scientists from 20 member countries.






larval dispersal
the spread of a species, fish and invertebrates, to a new location during the larvae stage. Many factors such as water flow, biological cues, chemical cues, environmental cues and larval mobility play roles in larval dispersal.
a commercial fishing technique that uses hundreds or even thousands of baited hooks attached to a single line. A controversial method because it can include bycatch.


see "grenadier".
any of several tropical evergreen trees or shrubs, which thrive in saline conditions along tidal shores or marshes. These plants are characterized by having above ground interlacing roots forming a unique and protected habitat for marine organisms, important nurseries for juvenile fish. Important to reduction of shore erosion.
manned submersibles
an underwater vehicle which has a life support environment within its structure from which the vehicle is controlled. These submersibles are capable of carrying scientists and technicians and diving to depths that are otherwise unreachable for first hand observation. These vehicles typically carry an array of instrumentation, manipulator arms, and specimen collection equipment which can be controlled by the scientist inside the submersible.
the cultivation of marine organisms in their natural habitats, usually for commercial purposes, also known as marine aquaculture.
relating to the ocean depths between 600ft (180m) and 3000ft (900m).
a mid-level predator which preys on lower trophic-order organisms, but which, in turn, is preyed upon by apex predator species.
relating to form or structure of an organism or one of its parts.
the quantitative measurement of the form of living systems or their parts.
mud volcanoes
formations created by geologically excreted liquids and gases, ejected materials are a mud-like mixture of fine solids suspended in liquids.


NEAFC (North East Atlantic Fisheries Commission)
an organization that recommends measures to maintain the rational exploitation of fish stocks in the Atlantic and Arctic Oceans.


ocean acidification
the decrease in the pH of the world's oceans, caused by their uptake of carbon dioxide from the atmosphere, much of which comes from anthropogenic sources.
the scientific study and exploration of the oceans and its contents.
the eating of both animal and plant foods.


relating to the open ocean, the zone begins at the low tide mark and extends to include the entire oceanic water column.
pelagic longline
a specific type of longline fishing which is characterized by the suspension of a long "trawl line" between buoys. From this trawl line hundreds or thousands of individual baited hooks are suspended in to the water column. This method is used in the open sea to target pelagic species such as swordfish, tuna, and sharks.
the horny or chitinous outer covering that protects the soft parts of hydrozoans.
relating to the evolutionary development and history of organisms.
pillow basalt substrate
a seafloor substrate characterized by globule or pillow shaped basalt formations which are created when magma extrudes into cold sea-water.
the amount of organic matter, carbon, or energy content that is accumulated during a given amount of time.
an unusual claw-like structure specific to certain arthropod groups.




the influx of new members of a population by reproduction or immigration.
remote sensing analysis
analysis of data produced by remote sensing technologies such as satellite observation, aircraft deployed instruments, or buoy deployed instruments.
remotely operated vehicles (ROV)
a submersible vehicle which is small, un-manned, and is operated via a cable, which connects the vehicle and it's sensors and instrument arrays to operators aboard a research vessel.
ROV Kaiko
a deep-diving research ROV which was owned and operated by JAMSTEC, the Japanese Agency for Marine-Earth Science and Technology. Kaiko was capable of diving to depths up to 7,000 m. Kaiko was lost at sea on May 29, 2003 after completing its 296th dive.


satellite telemetry tracking
a technology used to track the movement of tagged animals. This system utilizes a transmitter, which is placed on the animal in the form of an inserted tag, a collar, etc. This transmitter then broadcasts a signal which is used by one or several satellites to indentify the geographic location of the animal.
any member of the order Cnidaria categorized by the ability to produce a calcareous skeleton with hexameral symmetry, also known as the "hard corals".
an underwater mountain having a summit below the ocean surface, usually isolated and volcanic in origin.
SEaOS (Southern Elephant Seals as Oceanographic Samplers)
an international, interdisciplinary program aimed at increasing our understanding of how southern elephant seals interact with their environment. The program involves the tagging of seals with animal-mounted instrument arrays that track and broadcast location information as well as oceanographic data to researchers.
not free moving, permanently fixed or attached to a substrate, such as a barnacle.
a stiff hair, bristle, or bristle like part on an organism.
spiny lobster
any various edible marine decapod crustaceans lacking the large pincers characteristic of true lobsters, characteristically having a spiny carapace, usually found in warm water.
the reproductive zooids of hydrozoans.
a surface on which an organism grows or is attached, can serve as a source of food or to provide support.
sulphur bacteria
any bacterium of the genus Thiobacillus. These bacteria are characterized by having a metabolism that is driven by the oxidation of sulfurous compounds.
a characteristic of a process or state that can be maintained at a certain level indefinitely.


the science of dealing with the description, identification, naming, and classification of organisms.
tectonic plates
the individual sections of the Earth's crust. The theory of plate tectonics describes that these individuals sections are in flux and that the movement of these plates in relation to one another is responsible for seismic activity and the formation of geologic features such as mountains, trenches, etc.
automatic transmission and measurement of data or information from remote sources by wire or radio or other means to a monitoring station. Used to track the movements of organisms tagged with radio transmitters.
television-assisted grab
specimen collection technique which utilizes a camera mounted to an remotely operated vehicle which delivers a live feed which is used by operators to guide collections implements, in this case a grab sampler.
any member of the family Thalaassinidae, a family of burrowing Crustacea, having a long and soft abdomen.
a fishing or collecting technique in which a cone-shaped, closed-ended net is pulled through the water-column behind a vessel. This method can be employed either within the water column at various depths (mid-water trawl) or on the bottom of the water body (bottom trawl).
trophic level
any of the sequential stages in a food chain, occupied by producers at the bottom, followed by primary, secondary, and tertiary consumers.
trophic web
all of the interactions of predator and prey, included along with the exchange of nutrients into and out of the ecosystem. These interactions describe how energy is converted and passes from one organism to another and connect the various members of an ecosystem. Also known as a food web or food chain.