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Cetacean Bycatch
Cetacean bycatch (or cetacean by-catch) is the incidental capture of non-target cetacean species such as dolphins, porpoises, and whales by fisheries.Alverson et al. (1994) Bycatch can be caused by entanglement in fishing nets and lines, or direct capture by hooks or in trawl nets. Cetacean bycatch is increasing in intensity and frequency.Demaster et al. (2001) This is a trend that is likely to continue because of increasing human population growth and demand for marine food sources, as well as industrialization of fisheries which are expanding into new areas. These fisheries come into direct and indirect contact with cetaceans. An example of direct contact is the physical contact of cetaceans with fishing nets. Indirect contact is through marine trophic pathways where fisheries are severely reducing fish stocks that cetaceans rely on for food. In some fisheries, cetaceans are captured as bycatch but then retained because of their value as food or bait.Read et al. (2006) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fraser S Group
Fraser may refer to: Places Antarctica * Fraser Point, South Orkney Islands Australia * Fraser, Australian Capital Territory, a suburb in the Canberra district of Belconnen * Division of Fraser (Australian Capital Territory), a former federal electoral division located in the Australian Capital Territory * Division of Fraser (Victoria), a current federal electoral division located in Victoria * Fraser Island, along the coast of Queensland Canada * Fraser River ** Fraser Plateau, a subplateau of the Interior Plateau, named for the river ** Fraser Basin, a low-lying area, part of the Nechako Plateau, flanking the Fraser River in the Central Interior of British Columbia ** Fraser Canyon, the stretch of the Fraser River from the city of Williams Lake south to the town of Hope, British Columbia ** Fraser Valley, the region flanking the lowermost reaches of the Fraser River, from the town of Hope to the sea ** Fraser Plateau and Basin complex, a World Wildlife Fund-named ecoregion in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bycatch
Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juveniles of the target species. The term "bycatch" is also sometimes used for untargeted catch in other forms of animal harvesting or collecting. Non- marine species (freshwater fish not saltwater fish) that are caught (either intentionally or unintentionally) but regarded as generally "undesirable" are referred to as "rough fish" (mainly US) and " coarse fish" (mainly UK). In 1997, the Organisation for Economic Co-operation and Development (OECD) defined bycatch as "total fishing mortality, excluding that accounted directly by the retained catch of target species". Bycatch contributes to fishery decline and is a mechanism of overfishing for unintentional catch. The average annual bycatch rate of pinnipeds and cetaceans in the US from 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queensland
) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_date = Colony of Queensland , established_title2 = Separation from New South Wales , established_date2 = 6 June 1859 , established_title3 = Federation , established_date3 = 1 January 1901 , named_for = Queen Victoria , demonym = , capital = Brisbane , largest_city = capital , coordinates = , admin_center_type = Administration , admin_center = 77 local government areas , leader_title1 = Monarch , leader_name1 = Charles III , leader_title2 = Governor , leader_name2 = Jeannette Young , leader_title3 = Premier , leader_name3 = Annastacia Palaszczuk ( ALP) , legislature = Parliament of Queensland , judiciary = Supreme Court of Queensland , national_representation = Parliament of Australia , national_representation_type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark Culling
Shark culling is the deliberate killing of sharks by government authorities, usually in response to one or more shark attacks. The term "shark control" is often used by governments when referring to culls. Shark culling has been criticized by environmentalists, conservationists and animal welfare advocates—they say killing sharks harms the marine ecosystem and is unethical. Government officials often cite public safety (attempting to reduce the risk of shark attacks) as a reason for culling. The impact of culling is also minor compared to bycatch with 50 million sharks caught each year by the commercial fishing industry. Shark culling mainly occurs in four locations: New South Wales, Queensland, KwaZulu-Natal and Réunion. Carl Meyer, a researcher at the Hawaii Institute of Marine Biology, calls the disagreements about shark culling a "philosophical" debate, about "whether it is ethical to kill large predators in order to make the natural environment a safer playground for human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Turtle
Sea turtles (superfamily Chelonioidea), sometimes called marine turtles, are reptiles of the order Testudines and of the suborder Cryptodira. The seven existing species of sea turtles are the flatback, green, hawksbill, leatherback, loggerhead, Kemp's ridley, and olive ridley sea turtles. All six of the sea turtle species present in US waters (all of those listed above except the flatback) are listed as endangered and/or threatened under the Endangered Species Act. The seventh sea turtle species is the flatback, which exists in the waters of Australia, Papua New Guinea and Indonesia. Sea turtles can be separated into the categories of hard-shelled (cheloniid) and leathery-shelled ( dermochelyid).Wyneken, J. 2001. The Anatomy of Sea Turtles. U.S Department of Commerce NOAA Technical Memorandum NMFS-SEFSC-470, 1-172 pp. There is only one dermochelyid species which is the leatherback sea turtle. Description For each of the seven types of sea turtles, females and males are the sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Bird
Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period, and modern seabird families emerged in the Paleogene. In general, seabirds live longer, breed later and have fewer young than other birds do, but they invest a great deal of time in their young. Most species nest in colonies, which can vary in size from a few dozen birds to millions. Many species are famous for undertaking long annual migrations, crossing the equator or circumnavigating the Earth in some cases. They feed both at the ocean's surface and below it, and even feed on each other. Seabirds can be highly pelagic, coastal, or in some cases spend a part of the year away from the sea entirely. Seabirds and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sperm Whale
The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the genus ''Physeter'' and one of three extant species in the sperm whale family, along with the pygmy sperm whale and dwarf sperm whale of the genus ''Kogia''. The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of the mating season. The females cooperate to protect and nurse their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature sperm whale has few natural predators, although calves and weakened adults are sometimes killed by pods of killer whales (orcas). Mature males average in length, with the head representing up to one-third of the animal's length. Plunging to , it is the third deep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toothed Whale
The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of toothed whales are described. They are one of two living groups of cetaceans, the other being the baleen whales (Mysticeti), which have baleen instead of teeth. The two groups are thought to have diverged around 34 million years ago (mya). Toothed whales range in size from the and vaquita to the and sperm whale. Several species of odontocetes exhibit sexual dimorphism, in that there are size or other morphological differences between females and males. They have streamlined bodies and two limbs that are modified into flippers. Some can travel at up to 20 knots. Odontocetes have conical teeth designed for catching fish or squid. They have well-developed hearing, that is well adapted for both air and water, so much so that some can surviv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Driftnet
Drift netting is a fishing technique where nets, called drift nets, hang vertically in the water column without being anchored to the bottom. The nets are kept vertical in the water by floats attached to a rope along the top of the net and weights attached to another rope along the bottom of the net.Caddell, R."Caught in the net: driftnet fishing restrictions and the european court of justice" "Journal of Environmental Law", 2010 Drift nets generally rely on the entanglement properties of loosely affixed netting. Folds of loose netting, much like a window drapery, snag on a fish's tail and fins and wrap the fish up in loose netting as it struggles to escape. However the nets can also function as gill nets if fish are captured when their gills get stuck in the net. The size of the mesh varies depending on the fish being targeted. These nets usually target schools of pelagic fish. Traditionally drift nets were made of organic materials, such as hemp, which were biodegradable. Prio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longline Fishing
Longline fishing, or longlining, is a commercial fishing angling technique that uses a long ''main line'' with baited hooks attached at intervals via short branch lines called ''snoods'' or ''gangions''.Method and Apparatus for Long Line and Recreational Bait Fishing Patent application 20080202013. 28 August 2008. A snood is attached to the main line using a clip or swivel, with the hook at the other end. Longlines are classified mainly by where they are placed in the . This can be at the surface or at the bottom. Lines can also be set by means of an anchor, or left to drift. Hundreds or even thousands of baited hooks can hang from a single line. This can l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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