Extended Operational and Trade Vocabulary

Marine Biology, Fisheries and Oceanography glossary (page 2)

The biological and oceanographic vocabulary of the sea: ocean depth zones (abyssal, abyssopelagic), named taxa such as the crown-of-thorns starfish and calanoid copepods, plankton and productivity, acidification, and the physical setting of the abyssal plain. The species-and-ecology counterpart to the physical oceanography section, grounded in named organisms and water-column structure.

722 defined terms.

Showing 250 on this page (page 2 of 3).

F

Fucoid: Brown algae of the order Fucales (e.g., *Fucus*, *Sargassum*).

G

Gadidae: Family of cod, haddock, pollock, hake-like fishes (in part), and related gadiforms.
Galapagos Islands: Pacific archipelago and marine reserve straddling the equator off Ecuador.
Gannet: Large plunge-diving seabird of the genus *Morus*.
Gear-restricted area: Zone where specific fishing gears are prohibited.
Geodetic datum: Reference framework for positions on the Earth's surface.
Geoid: Equipotential surface of Earth's gravity field approximating mean sea level.
Geomorphology (marine): Study of the form and origin of seafloor features.
Geostrophic flow: Horizontal current in balance between Coriolis force and the horizontal pressure gradient.
Ghost Fishing: Continued capture of marine animals by lost or abandoned gear.
Gillnet: Vertical panel of net that captures fish by entanglement around the gills.
Glaucothoe: Larval stage of hermit crabs between zoea and juvenile.
Global Ocean Observing System (GOOS): IOC-UNESCO coordinated framework for sustained ocean observation.
Goby: Small bottom-dwelling fish of the family Gobiidae.
GPS-based station-keeping: Use of GPS for dynamic positioning during oceanographic operations.
Grand Banks: Atlantic fishing grounds off Newfoundland, central to cod history.
Gray whale: *Eschrichtius robustus*, a baleen whale of the North Pacific.
Great Australian Bight: Open bay of the Southern Ocean along southern Australia.
Great Barrier Reef: World's largest coral reef system, off the Queensland coast of Australia.
Green turtle: *Chelonia mydas*, a herbivorous sea turtle.
Greenhouse gas (ocean uptake): Approximately 25 percent of anthropogenic CO2 is absorbed by the ocean.
Grey seal: *Halichoerus grypus*, a large North Atlantic phocid.
Groundfish: Demersal fish targeted in trawl fisheries (e.g., cod, haddock, pollock, flatfish).
Group Velocity: Speed at which wave energy or a wave group travels.
Growth Overfishing: Removing fish before they reach optimal size.
Gulf of Aden: Embayment between Yemen and Somalia connecting the Red Sea and the Arabian Sea.
Gulf of Alaska: Marginal sea of the North Pacific along southern Alaska.
Gulf of Bothnia: Northern arm of the Baltic Sea between Sweden and Finland.
Gulf of California: Sea of Cortez, between Baja California and the Mexican mainland.
Gulf of Maine: Semi-enclosed sea on the U.S./Canada Atlantic coast.
Gulf of Mexico: Atlantic basin bordered by the U.S., Mexico, and Cuba.
Gulf of Thailand: Shallow embayment of the South China Sea.
Gulf Stream: Warm western boundary current of the North Atlantic.
Gulf Stream Rings: Mesoscale warm- and cold-core eddies shed from Gulf Stream meanders.

H

Habitat-Forming Species: Organisms that create three-dimensional structure, such as corals, seagrasses, and kelps.
Hadal zone: Ocean trenches, generally 6,000 to 11,000 m deep.
Haddock: *Melanogrammus aeglefinus*, a North Atlantic gadid.
Hadopelagic zone: Open-ocean water column within hadal trenches.
Hake: Members of the genera *Merluccius* and *Urophycis*, important demersal fishery resources.
Half-Beak: Surface-dwelling fish of the family Hemiramphidae.
Halibut: Large flatfish of the genus *Hippoglossus*.
Halocline: Vertical layer with a strong salinity gradient.
Halophyte: Salt-tolerant plant of saline habitats such as salt marshes.
Harbor porpoise: *Phocoena phocoena*, a small Northern Hemisphere odontocete.
Harbor seal: *Phoca vitulina*, a widespread coastal phocid of the Northern Hemisphere.
Harmful Algal Bloom (HAB): Algal bloom that causes harm to humans, ecosystems, or fisheries.
Harvest Control Rule (HCR): Pre-agreed rule linking management action to stock status.
HAT: Highest Astronomical Tide.
Hawaiian monk seal: *Neomonachus schauinslandi*, an endangered phocid endemic to Hawaii.
Hawksbill turtle: *Eretmochelys imbricata*, a critically endangered tropical sea turtle.
Headland eddy: Eddy formed in the lee of a coastal promontory.
Heat content (ocean): Total thermal energy stored in the ocean.
Herbivory: Feeding on plants or algae.
Hermatypic coral: Reef-building coral with symbiotic zooxanthellae.
Herring: *Clupea harengus* (Atlantic) and *Clupea pallasii* (Pacific), key forage fishes.
Heterotroph: Organism that obtains energy by consuming organic matter.
Hindcast: Model reconstruction of past conditions using observed forcing.
Hoki: *Macruronus novaezelandiae*, a New Zealand and southwestern Pacific gadid relative.
Holothurian: Sea cucumber, echinoderm of the class Holothuroidea.
Hudson Bay: Large inland sea of northern Canada.
Humboldt Current: Cold eastern boundary current along the west coast of South America.
Humpback whale: *Megaptera novaeangliae*, a cosmopolitan baleen whale known for breaching and song.
Hydrodynamics: Study of fluids in motion.
Hydrography: Science of surveying water bodies.
Hydrothermal Vent: Seafloor opening discharging geothermally heated water.
Hypoxia: Dissolved oxygen below threshold needed for many marine species, often less than 2 milligrams per liter.

I

IATTC: Inter-American Tropical Tuna Commission.
ICCAT: International Commission for the Conservation of Atlantic Tunas.
Ice edge: Boundary between open water and sea ice, often biologically productive.
Ice Shelf: Floating extension of an ice sheet.
Icelandic Current: Cold current flowing southward off western Iceland.
ICES: International Council for the Exploration of the Sea, providing scientific advice.
IHO: International Hydrographic Organization, intergovernmental body for hydrography.
IMTA: Integrated Multi-Trophic Aquaculture, co-cultivating species from different trophic levels.
In situ measurement: Measurement made directly in the environment.
Indian Ocean Dipole (IOD): Coupled ocean-atmosphere mode with SST anomalies across the tropical Indian Ocean.
Individual Transferable Quota (ITQ): Tradable fishing quota allocated to individuals or vessels.
Indo-Pacific bottlenose dolphin: *Tursiops aduncus*.
Infauna: Animals living within seabed sediments.
Inshore: Toward the shore.
Internal Tide: Internal wave generated at tidal frequencies by tide-topography interactions.
Internal Wave: Wave propagating within a stratified fluid along density interfaces.
Invertebrate: Animal lacking a vertebral column.
IOC: Intergovernmental Oceanographic Commission of UNESCO.
IOTC: Indian Ocean Tuna Commission.
IPHC: International Pacific Halibut Commission.
Iridium-based telemetry: Satellite communications widely used by oceanographic instruments.
Irminger Sea: Region of the North Atlantic east of Greenland, site of deep convection.
Isobar: Line of equal atmospheric pressure on synoptic chart.
Isohaline: Line of constant salinity.
Isopod: Crustacean of the order Isopoda, including marine forms like *Bathynomus giganteus*.
Isopycnal: Surface of constant potential density.
Isotherm: Line of constant temperature.
ITCZ: Intertropical Convergence Zone, the band of low pressure near the equator.
IUU Fishing: Illegal, unreported, and unregulated fishing.

J

Jack mackerel: Schooling pelagic of the genus *Trachurus*.
Japan Sea: Marginal sea of the western Pacific, also called the East Sea.
Jellyfish: Gelatinous medusa of the phylum Cnidaria.
JONSWAP spectrum: Joint North Sea Wave Project spectral form.
Juvenile: Immature post-larval life stage.

K

Kara Sea: Marginal Arctic sea north of Siberia.
Kattegat: Sea between Denmark and Sweden linking the Baltic and North Seas.
Kelp: Large brown algae of the order Laminariales.
Kelp forest: Subtidal canopy ecosystem dominated by kelps, especially *Macrocystis* and *Nereocystis*.
Kelvin Wave: Trapped wave that propagates along a boundary or the equator without dispersion.
Kemp's ridley turtle: *Lepidochelys kempii*, the world's most endangered sea turtle.
Killer whale: *Orcinus orca*, the largest dolphin and an apex predator.
King crab: Lithodid crab of the genera *Paralithodes*, *Lithodes*, etc.
King mackerel: *Scomberomorus cavalla*, a Western Atlantic scombrid.
Krill: Shrimp-like crustaceans of the order Euphausiacea.
Kuroshio Current: Warm western boundary current of the North Pacific off Japan.
Kuroshio Extension: Eastward-flowing free jet east of Japan after the Kuroshio separates from the coast.

L

Labrador Current: Cold southward current along the east coast of Canada.
Labrador Sea: Sea between Labrador and Greenland, site of deep convection.
Lagoon: Shallow body of water separated from a larger body by a barrier such as a reef or barrier island.
Lagrangian Measurement: Observation following a moving water parcel.
Laptev Sea: Marginal Arctic sea between the Taymyr Peninsula and the New Siberian Islands.
Larvacea: Pelagic tunicates (Appendicularia) producing mucus houses that sink as marine snow.
Larvae: Immature life stage morphologically distinct from the adult.
LAT: Lowest Astronomical Tide.
Latent Heat Flux: Heat exchanged with the atmosphere through evaporation or condensation.
Leatherback turtle: *Dermochelys coriacea*, the largest living turtle.
Length at first maturity (Lm): Body length at which 50 percent of individuals are reproductively mature.
Length frequency: Distribution of body lengths in a catch or population.
Leptocephalus: Transparent ribbon-like larva of eels and tarpons.
Levantine Sea: Easternmost basin of the Mediterranean.
Light attenuation coefficient (Kd): Rate at which downwelling light decreases with depth.
Ligurian Sea: Northwestern arm of the Mediterranean between Corsica and the Italian Riviera.
Lionfish: Indo-Pacific scorpaenids *Pterois volitans* and *Pterois miles*, invasive in the western Atlantic.
Littoral zone: Intertidal zone between high and low tide marks.
Loggerhead turtle: *Caretta caretta*, a temperate and tropical sea turtle.
Longline: Fishing line with many baited hooks.
Longshore Current: Wave-driven current parallel to shore in the surf zone.
Lophelia pertusa: Cold-water reef-forming coral, now classified as *Desmophyllum pertusum*.
Lugworm: Polychaete *Arenicola marina* of intertidal sandflats.
Lutjanidae: Family of snappers, including red snapper (*Lutjanus campechanus*).

M

Mackerel: Pelagic scombrid fishes of the genus *Scomber* and related taxa.
Macroalgae: Multicellular algae visible to the unaided eye.
Macrocystis pyrifera: Giant kelp, foundation species of eastern Pacific kelp forests.
MAGNUS act / Magnuson-Stevens Act: U.S. law governing federal marine fisheries (16 USC 1801).
Mahi-mahi: *Coryphaena hippurus*, the common dolphinfish.
Mako shark: Fast-swimming lamnid shark of the genus *Isurus*.
Mangrove: Salt-tolerant tree forming intertidal forests in the tropics and subtropics.
Manta ray: Large planktivorous batoid of the genus *Mobula* (formerly *Manta*).
Mariana Trench: Deepest known oceanic trench, in the western Pacific.
Marine Debris: Solid persistent wastes in the marine environment.
Marine Heatwave (MHW): Persistent anomalously warm sea surface temperature event.
Marine Protected Area (MPA): Geographically defined area managed for conservation.
Marine snow: Falling aggregates of organic detritus that fuel the deep-sea food web.
Marine Stewardship Council (MSC): NGO that certifies sustainable wild-capture fisheries.
Marlin: Large pelagic billfishes of the family Istiophoridae.
Maximum Economic Yield (MEY): Catch level maximizing resource rent.
Maximum Sustainable Yield (MSY): Largest catch that can on average be taken indefinitely.
Mean Higher High Water (MHHW): Average of higher high waters over a tidal datum epoch.
Mean Lower Low Water (MLLW): Average of lower low waters, common datum in US waters.
Mean sea level (MSL): Average level of the sea surface.
Mediterranean Sea: Marginal sea between Europe, Africa, and Asia.
Medusa: Free-swimming adult life stage of jellyfish.
Megafauna: Large marine animals, often defined as greater than 45 kg.
Mekong Delta: Major river delta on the South China Sea coast of Vietnam.
Mendocino Fracture Zone: Major Pacific seafloor fracture zone off northern California.
Mesoderm: Embryological tissue layer; in jellyfish lineages is jelly-like mesoglea.
Mesopelagic zone: Twilight ocean layer from about 200 to 1,000 m depth.
Mesoscale Eddy: Coherent rotating ocean feature with scales of tens to hundreds of kilometers.
Microbial loop: Pathway in which dissolved organic matter is returned to the food web via heterotrophic bacteria.
Microplastics: Plastic particles smaller than 5 mm.
Microzooplankton: Zooplankton in the size range 20 to 200 micrometers, including ciliates and dinoflagellates.
Mid-Atlantic Ridge: Slow-spreading mid-ocean ridge bisecting the Atlantic.
Mid-Ocean Ridge: Submarine mountain range where new oceanic crust forms.
Migration (vertical): Diel vertical movement of organisms in the water column.
Minke whale: Small baleen whales of the genus *Balaenoptera* (*B. acutorostrata* in N hemisphere, *B. bonaerensis* in S).
Mixed Layer Depth (MLD): Depth marking the base of the surface mixed layer.
Mixed Tide: Tide with significant diurnal and semidiurnal components.
Molting: Periodic shedding of the exoskeleton by crustaceans.
Monkfish: Lophiid anglerfishes of the genus *Lophius*.
Monsoon: Seasonally reversing wind system bringing strong climatic forcing, especially in the Indian Ocean.
MPA: Marine Protected Area.
Mullet: Schooling coastal fish of the family Mugilidae.
Multibeam echosounder: Hydrographic sonar emitting a swath of beams to map bathymetry.
Mussel: Bivalve mollusk of the families Mytilidae and Dreissenidae; intertidal and subtidal.
Mysid: Small shrimp-like crustacean of the order Mysida.
Mysticete: Member of the cetacean suborder Mysticeti (baleen whales).

N

NAFO: Northwest Atlantic Fisheries Organization.
Nansen Bottle: Classical water sampler used before electronic CTDs.
Narwhal: *Monodon monoceros*, Arctic odontocete with a long spiraled tusk.
Nautilus: Cephalopod of the genus *Nautilus* with an external chambered shell.
NEAFC: North East Atlantic Fisheries Commission.
Neap Tide: Tide with smallest range, near first and third lunar quarters.
Nekton: Free-swimming animals strong enough to move against currents (fish, squid, marine mammals).
Neritic zone: Coastal pelagic zone over the continental shelf.
Net Primary Production (NPP): Rate of photosynthetic carbon fixation minus respiration by primary producers.
Niskin bottle: Modern cylindrical water sampler used on CTD rosettes.
Nitrate (NO3-): Principal inorganic nitrogen nutrient in oxygenated seawater.
Nitrite (NO2-): Intermediate in nitrogen cycling between ammonium and nitrate.
Nitrogen fixation: Conversion of N2 to ammonia, performed by cyanobacteria such as *Trichodesmium*.
No-Take Zone: MPA where extractive activities are prohibited.
NOAA: National Oceanic and Atmospheric Administration of the United States.
North Atlantic Deep Water (NADW): Cold, dense water mass formed in the northern North Atlantic.
North Atlantic Oscillation (NAO): Climate mode based on the pressure difference between Iceland and the Azores.
North Pacific Gyre: Subtropical anticyclonic circulation of the North Pacific.
North Sea: Shelf sea between Britain and continental Europe.
Norway pout: *Trisopterus esmarkii*, a small gadid used for fishmeal.
Norwegian Sea: Sea between Norway and the Greenland-Iceland-Faroes ridge.
Notothenioid: Antarctic icefishes and relatives, many with antifreeze glycoproteins.
Nudibranch: Shell-less marine gastropod (sea slug) of the clade Nudibranchia.
Nutricline: Vertical layer with strong nutrient concentration gradient.

O

Ocean Acidification: Long-term decrease in seawater pH from CO2 uptake.
Ocean Color: Visible light reflectance used to estimate phytoplankton and CDOM.
Ocean conveyor belt: Conceptual model of global thermohaline circulation.
Oceanic Whitetip shark: *Carcharhinus longimanus*.
Octopus: Cephalopod of the order Octopoda with eight arms.
Odontocete: Member of the cetacean suborder Odontoceti (toothed whales).
Offshore: Waters beyond the inshore zone, often beyond the continental shelf.
Oil spill: Accidental release of petroleum into the marine environment.
Olive ridley turtle: *Lepidochelys olivacea*, sea turtle famous for mass nesting (arribadas).
OMZ: Oxygen Minimum Zone, a midwater layer of very low dissolved oxygen.
Operational oceanography: Sustained provision of routine ocean data, forecasts, and services.
Orange roughy: *Hoplostethus atlanticus*, a long-lived deep-sea fish.
OSPAR: Convention for the Protection of the Marine Environment of the North-East Atlantic.
Otolith: Calcium carbonate structure in fish inner ear used for age determination.
Outfall: Discharge structure releasing wastewater to the sea.
Overfishing: Fishing at levels above sustainable mortality.
Oxygen Minimum Zone (OMZ): Mid-depth layer with very low dissolved oxygen concentrations.
Oyster: Bivalve mollusk of the families Ostreidae and Pteriidae; key aquaculture species.
Ozone-related UV: UV-B reaching surface waters can affect surface plankton.

P

Pacific Cod: *Gadus macrocephalus*, North Pacific gadid fishery species.
Pacific Decadal Oscillation (PDO): Long-lived ENSO-like pattern of Pacific climate variability.
Pacific halibut: *Hippoglossus stenolepis*, large flatfish managed by IPHC.
Pacific sardine: *Sardinops sagax*, small pelagic of the eastern Pacific.
Pack ice: Floating sea ice driven together into a mass by wind and currents.
Parrotfish: Reef herbivore of the family Scaridae that erodes carbonate substrate.
Patagonian toothfish: *Dissostichus eleginoides*, Southern Ocean fishery species sold as Chilean sea bass.
PCBs (polychlorinated biphenyls): Persistent organic pollutants bioaccumulating in marine food webs.
Pelagic: Pertaining to the open water column.
Pelagic longline: Surface or midwater longline targeting tunas, swordfish, and sharks.
Pen-reared salmon: Salmon farmed in floating sea cages, principally Atlantic salmon.
Penguin: Flightless seabird of the family Spheniscidae, mostly Southern Hemisphere.
Persian Gulf: Shallow marginal sea between Iran and the Arabian Peninsula.
Petrel: Pelagic seabird of the order Procellariiformes.
pH: Negative logarithm of hydrogen ion activity, central to ocean acidification studies.
Phocidae: True (earless) seals.
Phosphate (PO4 3-): Principal inorganic phosphorus nutrient in seawater.
Photic Zone: Surface layer with sufficient light for photosynthesis.
Photosynthetically Active Radiation (PAR): Spectral range driving photosynthesis, 400 to 700 nanometers.
Phytoplankton: Microscopic photosynthetic plankton including diatoms, dinoflagellates, cyanobacteria, and coccolithophores.
Pierson-Moskowitz spectrum: Fully developed sea spectrum.
Pilot whale: Large dolphins of the genus *Globicephala*.
Pinniped: Fin-footed marine mammal (seals, sea lions, walrus).
Plaice: *Pleuronectes platessa*, a North Atlantic flatfish.
Plankton: Drifting aquatic organisms unable to swim against currents.