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Salmon Run
A salmon run is an annual fish migration event where many salmonid species, which are typically hatched in fresh water and live most of their adult life downstream in the ocean, swim back against the stream to the upper reaches of rivers to spawn (biology), spawn on the gravel beds of small stream, creeks. After spawning, most Atlantic salmon and all species of Oncorhynchus, Pacific salmon die, and the salmon biological life cycle, life cycle starts over again with the new generation of hatchlings. Salmon are anadromous, spending their juvenile fish, juvenile life in rivers or lakes, and then migrating out to sea where they spend adult lives and gain most of their body mass. When they reach sexual maturity, the adults return to the upstream rivers to reproduce. Usually they natal homing, return with uncanny precision to the natal river where they were born, and even to the very spawning ground of their birth. It is thought that, when they are in the ocean, they use magnetorece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grizzly Bear Fishing Brooks Falls (flipped)
The grizzly bear (''Ursus arctos horribilis''), also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear inhabiting North America. In addition to the mainland grizzly (''Ursus arctos horribilis''), other morphological forms of brown bear in North America are sometimes identified as grizzly bears. These include three living populations—the Kodiak bear (''U. a. middendorffi''), the Kamchatka bear (''U. a. beringianus''), and the peninsular grizzly (''U. a. gyas'')—as well as the extinct California grizzly (''U. a. californicus''†) and Mexican grizzly (formerly ''U. a. nelsoni''†). On average, grizzly bears near the coast tend to be larger while inland grizzlies tend to be smaller. The Ussuri brown bear (''U. a. lasiotus''), inhabiting the Ussuri Krai, Sakhalin, the Amur Oblast, the Shantar Islands, Iturup Island, and Kunashir Island in Siberia, northeastern China, North Korea, and Hokkaidō in Japan, is sometime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adult
An adult is an animal that has reached full growth. The biological definition of the word means an animal reaching sexual maturity and thus capable of reproduction. In the human context, the term ''adult'' has meanings associated with social and legal concepts. In contrast to a non-adult or " minor", a legal adult is a person who has attained the age of majority and is therefore regarded as independent, self-sufficient, and responsible. They may also be regarded as "majors". The typical age of attaining legal adulthood is 18 although definition may vary by legal rights, country, and psychological development. Human adulthood encompasses psychological adult development. Definitions of adulthood are often inconsistent and contradictory; a person may be biologically an adult, and have adult behavior, but still be treated as a child if they are under the legal age of majority. Conversely, one may legally be an adult but possess none of the maturity and responsibility that may de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brackish
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root '' brak''. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it can be damaging to the environment (see article on shrimp farms). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seawater
Seawater, or sea water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has approximately of dissolved salts (predominantly sodium () and chloride () ions). The average density at the surface is 1.025 kg/L. Seawater is denser than both fresh water and pure water (density 1.0 kg/L at ) because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases. At typical salinity, it freezes at about . The coldest seawater still in the liquid state ever recorded was found in 2010, in a stream under an Antarctic glacier: the measured temperature was . Seawater pH is typically limited to a range between 7.5 and 8.4. However, there is no universally accepted reference pH-scale for seawater and the difference between measuremen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Trout
Sea trout is the common name usually applied to anadromous (sea-run) forms of brown trout (''Salmo trutta''), and is often referred to as ''Salmo trutta'' morpha ''trutta''. Other names for anadromous brown trout are bull trout, sewin (Wales), peel or peal (southwest England), mort (northwest England), finnock (Scotland), white trout (Ireland) and salmon trout (culinary). The term "sea trout" is also used to describe other anadromous salmonids, such as coho salmon (''Oncorhynchus kisutch''), coastal cutthroat trout (''Oncorhynchus clarkii clarkii''), brook trout (''Salvelinus fontinalis''), Arctic char (''Salvelinus alpinus alpinus'') and Dolly Varden (''Salvenlinus malma''). Even some non-salmonid fish species are also commonly known as sea trout, such as Northern pikeminnow (''Ptychocheilus oregonensis'') and members of the weakfish family (''Cynoscion''). Range Anadromous brown trout are widely distributed in Europe along the Atlantic and Baltic coasts, the United Kin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steelhead
Steelhead, or occasionally steelhead trout, is the Fish migration#Classification, anadromous form of the coastal rainbow trout or Columbia River redband trout (''O. m. gairdneri'', also called redband steelhead). Steelhead are native to cold-water tributaries of the Pacific basin in Northeast Asia and North America. Like other sea-run (anadromous) trout and salmon, steelhead spawn (biology), spawn in freshwater, Juvenile salmon, smolts migrate to the ocean to forage for several years and adults return to their natal streams to spawn. Steelhead are iteroparous, although their survival rate is approximately only 10–20%. Description The freshwater form of the steelhead is the rainbow trout (''Oncorhynchus mykiss''). The difference between these forms of the species is that steelhead migrate to the ocean and return to freshwater tributaries to spawn, whereas non-anadromous rainbow trout do not leave freshwater. Steelhead are also larger and less colorful than rainbow trout. St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamodromous
Fish migration is animal migration, mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear. Fish migrations involve movements of school of fish, schools of fish on a scale and duration larger than those arising during normal daily activities. Some particular types of migration are ''anadromous'', in which adult fish live in the sea and migrate into fresh water to spawn (biology), spawn; and ''catadromous'', in which adult fish live in fresh water and migrate into salt water to spawn. Marine forage fish often make large migrations between their spawning, feeding and nursery grounds. Their movements are associated with ocean currents and with the availability of food in different area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trout
Trout (: trout) is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of which are members of the subfamily Salmoninae in the family Salmonidae. The word ''trout'' is also used for some similar-shaped but non-salmonid fish, such as the spotted seatrout/speckled trout (''Cynoscion nebulosus'', which is actually a croaker). Trout are closely related to salmon and have similar migratory life cycles. Most trout are strictly potamodromous, spending their entire lives exclusively in freshwater lakes, rivers and wetlands and migrating upstream to spawn in the shallow gravel beds of smaller headwater creeks. The hatched fry and juvenile trout, known as ''alevin'' and ''parr'', will stay upstream growing for years before migrating down to larger waterbodies as maturing adults. There are some anadromous species of trout, such as the steelhead (a coastal subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homing (biology)
Homing is the inherent ability of an animal to navigate towards an original location (geography), location through unfamiliar areas. This location may be a home territory or a breeding spot. Uses Homing abilities can be used to find the way back to home in a wikt:migration, migration. It is often used in reference to going back to a breeding spot seen years before, as in the case of salmon. Homing abilities can also be used to go back to familiar territory when displaced over long distances, such as with the red-bellied newt. True navigation Some animals use true navigation for their homing. This means in familiar areas they will use landmarks such as roads, rivers or mountains when flying, or islands and other landmarks while swimming. However, this only works in familiar territory. Homing pigeons, for example, will often navigate using familiar landmarks, such as roads. Sea turtles will also use landmarks to orient themselves.Avens, L., (2003) "Homing Behavior, Navigation, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetoreception
Magnetoreception is a sense which allows an organism to detect the Earth's magnetic field. Animals with this sense include some arthropods, molluscs, and vertebrates (fish, amphibians, reptiles, birds, and mammals). The sense is mainly used for orientation and navigation, but it may help some animals to form regional maps. Experiments on migratory birds provide evidence that they make use of a cryptochrome protein in the eye, relying on the quantum radical pair mechanism to perceive magnetic fields. This effect is extremely sensitive to weak magnetic fields, and readily disturbed by radio-frequency interference, unlike a conventional iron compass. Birds have iron-containing materials in their upper beaks. There is some evidence that this provides a magnetic sense, mediated by the trigeminal nerve, but the mechanism is unknown. Cartilaginous fish including sharks and stingrays can detect small variations in electric potential with their electroreceptive organs, the ampulla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natal Homing
Natal homing, or natal philopatry, is the homing process by which some adult animals that have migrated away from their juvenile habitats return to their birthplace to reproduce. This process is primarily used by aquatic animals such as sea turtles and salmon, although some migratory birds and mammals also practice similar reproductive behaviors. Scientists believe that the main cues used by the animals are geomagnetic imprinting and olfactory cues. The benefits of returning to the precise location of an animal's birth may be largely associated with its safety and suitability as a breeding ground. When seabirds like the Atlantic puffin return to their natal breeding colony, which are mostly on islands, they are assured of a suitable climate and a sufficient lack of land-based predators. Sea turtles born in any one area differ genetically from turtles born in other areas. The newly hatched young head out to sea and soon find suitable feeding grounds, and it has been shown that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
