Oceans and Fisheries

Vocabulary flashcards covering ocean resources, world fisheries, environmental impacts of overfishing, and fisheries management strategies.

Desalination

The purification process used to remove salt from ocean water to make safe drinking water.

Tidal energy

Energy generated by seawater moving up and down twice a day, driven by the gravitational pull of the Sun and Moon.

Wave energy

Energy contained in ocean waves that, if harnessed, could produce approximately twice the world's present energy production.

Bulk carriers

Ships designed to transport unpackaged bulk food commodities such as rice and wheat.

Container ships

Vessels specialized in transporting general cargo packed in large, standardized containers.

Tankers

Ships designed to carry bulk liquids, especially LPG, LNG, vegetable oils, and wine.

Refrigerated ships

Ships equipped with temperature-controlled holds to carry perishable items such as fruit, vegetables, dairy, and fish.

Roll-on/roll-off ships

Vessels specifically designed to carry wheeled cargo, including motor vehicles and their loads.

Surface currents

The continuous movement of surface seawater traveling in a constant direction.

Prevailing wind

The dominant direction from which the wind usually blows in a given region.

Continental shelf

The shallow seabed bordering a continent where water depth is $< 150\,m$, providing high levels of light and oxygen that support major fisheries.

Euphotic zone

The uppermost ocean layer extending down to approximately $\sim 200\,m$, where sufficient sunlight penetrates for photosynthesis to occur.

Ocean floor topography

The structural profile of the seafloor extending from the coast, consisting of the continental shelf, continental slope, continental rise, and abyssal plain.

Phytoplankton

Microscopic marine organisms that carry out photosynthesis using light, water, and $CO_2$, forming the base of marine food webs.

Limiting factor

The environmental factor affecting a biological or chemical process that is in the shortest supply.

Upwelling

The process by which ocean currents transport cold, mineral- and nutrient-rich waters from the ocean floor up to the surface.

Overfishing

The practice of catching fish faster than populations can reproduce, resulting in depleted fish stocks.

El Niño Southern Oscillation (ENSO)

A climatic event in which shifts in prevailing winds alter South Pacific currents, bringing warm, nutrient-poor water and halting the upwelling of cold, nutrient-rich water.

Bycatch

Non-target marine animals inadvertently caught during fishing operations and often discarded.

Trawl nets

Nets dragged through open water or across the seabed that capture non-target species and cause physical damage to the sea floor.

Drift nets

Unanchored fishing nets that move freely with the ocean current, commonly deployed in coastal waters.

Seine nets

Fishing nets designed to hang vertically like a curtain in the water column to enclose schooling fish.

Dredge nets

Heavy nets dragged along the seabed using teeth or water jets to dislodge and collect shellfish and mud-dwelling organisms.

Aquaculture

The commercial farming and cultivation of freshwater fish species.

Mariculture

A form of aquaculture carried out in marine environments, such as enclosed ocean sections, tanks, ponds, and raceways filled with seawater.

Fish aggregation devices (FADs)

Man-made structures such as suspended logs placed below the surface to attract tuna and other marine species, often resulting in high bycatch when encircled by nets.

Pole-and-line fishing

A selective fishing technique where fish are caught individually with a handheld pole and line, resulting in minimal or no bycatch.

Fishing quotas

Legally enforced governmental limits that specify the quantity and species of fish permitted to be harvested, designed to leave sufficient breeding stock.

Closed seasons

Designated periods of the year, typically during breeding times, when governments prohibit fishing to allow stocks to reproduce.

Magnuson-Stevens Fishery Conservation and Management Act

The primary federal law governing marine fisheries in the USA, establishing control over waters, conserving resources, and protecting habitats.

Economic exclusion zone (EEZ)

A coastal zone extending $200\text{ nautical miles}$ offshore within which a country has sovereign responsibility to manage fisheries sustainably.

UNCLOS

The United Nations Convention on the Law of the Sea, an international agreement providing regulations for fisheries and maritime activities in international waters.