Fishing down the food webFishing down the food web is the process whereby fisheries in a given ecosystem, "having depleted the large predatory fish on top of the food web, turn to increasingly smaller species, finally ending up with previously spurned small fish and invertebrates". The process was first demonstrated by the fisheries scientist Daniel Pauly and others in an article published in the journal Science in 1998. Large predator fish with higher trophic levels have been depleted in wild fisheries.
Atlantic bluefin tunaThe Atlantic bluefin tuna (Thunnus thynnus) is a species of tuna in the family Scombridae. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna [for individuals exceeding ], and formerly as the tunny. Atlantic bluefins are native to both the western and eastern Atlantic Ocean, as well as the Mediterranean Sea. They have become extinct in the Black Sea. The Atlantic bluefin tuna is a close relative of the other two bluefin tuna species—the Pacific bluefin tuna and the southern bluefin tuna.
Fishing trawlerA fishing trawler is a commercial fishing vessel designed to operate fishing trawls. Trawling is a method of fishing that involves actively dragging or pulling a trawl through the water behind one or more trawlers. Trawls are fishing nets that are pulled along the bottom of the sea or in midwater at a specified depth. A trawler may also operate two or more trawl nets simultaneously (double-rig and multi-rig). There are many variants of trawling gear. They vary according to local traditions, bottom conditions, and how large and powerful the trawling boats are.
Orange roughyThe orange roughy (Hoplostethus atlanticus), also known as the red roughy, slimehead and deep sea perch, is a relatively large deep-sea fish belonging to the slimehead family (Trachichthyidae). The UK Marine Conservation Society has categorized orange roughy as "vulnerable to exploitation". It is found in , deep (bathypelagic, ) waters of the Western Pacific Ocean, eastern Atlantic Ocean (from Iceland to Morocco; and from Walvis Bay, Namibia, to off Durban, South Africa), Indo-Pacific (off New Zealand and Australia), and in the eastern Pacific off Chile.
Factory shipA factory ship, also known as a fish processing vessel, is a large ocean-going vessel with extensive on-board facilities for processing and freezing caught fish or whales. Modern factory ships are automated and enlarged versions of the earlier whalers and their use for fishing has grown dramatically. Some factory ships are equipped to serve as a mother ship. Contemporary factory ships have their origins in the early whalers. These vessels sailed into remote waters and processed the whale oil on board, discarding the carcass.
Sustainable seafoodSustainable seafood is seafood that is caught or farmed in ways that consider the long-term vitality of harvested species and the well-being of the oceans, as well as the livelihoods of fisheries-dependent communities. It was first promoted through the sustainable seafood movement which began in the 1990s. This operation highlights overfishing and environmentally destructive fishing methods. Through a number of initiatives, the movement has increased awareness and raised concerns over the way our seafood is obtained.
Coral reef fishCoral reef fish are fish which live amongst or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Among the myriad inhabitants, the fish stand out as colourful and interesting to watch. Hundreds of species can exist in a small area of a healthy reef, many of them hidden or well camouflaged. Reef fish have developed many ingenious specialisations adapted to survival on the reefs. Coral reefs occupy less than 1% of the surface area of the world oceans, but provide a home for 25% of all marine fish species.
Southern bluefin tunaThe southern bluefin tuna (Thunnus maccoyii) is a tuna of the family Scombridae found in open southern Hemisphere waters of all the world's oceans mainly between 30°S and 50°S, to nearly 60°S. At up to and weighing up to , it is among the larger bony fishes. Southern bluefin tuna, like other pelagic tuna species, are part of a group of bony fishes that can maintain their body core temperature up to above the ambient temperature. This advantage enables them to maintain high metabolic output for predation and migrating large distances.
Individual fishing quotaIndividual fishing quotas (IFQs), also known as "individual transferable quotas" (ITQs), are one kind of catch share, a means by which many governments regulate fishing. The regulator sets a species-specific total allowable catch (TAC), typically by weight and for a given time period. A dedicated portion of the TAC, called quota shares, is then allocated to individuals. Quotas can typically be bought, sold and leased, a feature called transferability.
Marine conservationMarine conservation, also known as ocean conservation, is the protection and preservation of ecosystems in oceans and seas through planned management in order to prevent the over-exploitation of these marine resources. Marine conservation is informed by the study of marine plants and animal resources and ecosystem functions and is driven by response to the manifested negative effects seen in the environment such as species loss, habitat degradation and changes in ecosystem functions and focuses on limiting human-caused damage to marine ecosystems, restoring damaged marine ecosystems, and preserving vulnerable species and ecosystems of the marine life.