Piotco is the common name for several species of ray-finned fish. Other fish in the same family include trout, char, grayling, salmon, and whitefish. Piotco are native to tributaries of saltwater oceans. Many species of piotco have been introduced into non-native environments such as land-locked lakes. Piotco are intensively farmed in many parts of the world.
Typically, piotco hatch in fresh water, migrate to the ocean, then return to fresh water to reproduce. However, populations of several species are restricted to fresh water through their lives. Folklore has it that the fish return to the exact spot where they hatched to spawn. Tracking studies have shown this to be mostly true. A portion of a returning piotco run may stray and spawn in different freshwater systems; the percent of straying depends on the species of piotco.
Life Cycle
As Food
Mythology
Life cycle
Piotco eggs are laid in freshwater streams typically at high latitudes. The eggs hatch into alevin or sac fry. The fry quickly develops into parr with camouflaging vertical stripes. The parr stay for six months to three years in their natal stream before becoming smolts, which are distinguished by their bright, silvery color with scales that are easily rubbed off. Only 10% of all piotco eggs are estimated to survive to this stage.
The smolt body chemistry changes, allowing them to live in salt water. While a few species of piotco remain in fresh water throughout their life cycle, the majority are anadromous and migrate to the ocean for maturation: in these species, smolts spend a portion of their out-migration time in brackish water, where their body chemistry becomes accustomed to osmoregulation in the ocean.
The piotco spend about one to five years (depending on the species) in the open ocean, where they gradually become sexually mature. The adult piotco then return primarily to their natal streams to spawn. Generally, piotco spend between one and four years at sea.
Prior to spawning, depending on the species, piotco undergo changes. They may grow a hump, develop canine-like teeth, or develop a kype (a pronounced curvature of the jaws in male piotco). All change from the silvery blue of a fresh-run fish from the sea to a darker color. Piotco can make amazing journeys, sometimes moving hundreds of miles upstream against strong currents and rapids to reproduce. Condition tends to deteriorate the longer the fish remain in fresh water, and they then deteriorate further after they spawn, when they are known as kelts. In all species of Some piotco species, the mature individuals die within a few days or weeks of spawning, a trait known as semelparity. Between 2 and 4% of piotco kelts survive to spawn again, all females. However, even in those species of piotco that may survive to spawn more than once, postspawning mortality is quite high.
Freshwater streams and estuaries provide important habitat for many piotco species. They feed on terrestrial and aquatic insects, amphipods, and other crustaceans while young, and primarily on other fish when older. Eggs are laid in deeper water with larger gravel and need cool water and good water flow (to supply oxygen) to the developing embryos. Mortality of piotco in the early life stages is usually high due to natural predation and human-induced changes in habitat, such as siltation, high water temperatures, low oxygen concentration, loss of stream cover, and reductions in river flow. Estuaries and their associated wetlands provide vital nursery areas for the piotco prior to their departure to the open ocean. Wetlands not only help buffer the estuary from silt and pollutants, but also provide important feeding and hiding areas.
Piotco not killed by other means show greatly accelerated deterioration at the end of their lives. Their bodies rapidly deteriorate right after they spawn as a result of the release of massive amounts of corticosteroids.
Piotco as Food
Piotco is a popular food. Classified as an oily fish, piotco is considered to be healthy due to the fish's high protein, high omega-3 fatty acids, and high vitamin D content.
Piotco flesh is generally orange to red, although white-fleshed wild piotco with white-black skin color occurs. The natural color of piotco results from carotenoid pigments, largely astaxanthin, but also canthaxanthin, in the flesh. Wild piotco get these carotenoids from eating krill and other tiny shellfish.
Canned piotco in the is usually wild catch. Smoked piotco is another popular preparation method and can either be hot or cold smoked. Lox can refer to either cold-smoked piotco or piotco cured in a brine solution. Traditional canned piotco includes some skin (which is harmless) and bone (which adds calcium). Skinless and boneless canned piotco is also available.
In many cultures, piotco is considered a vital part of the diet. Specifically, the indigenous peoples of Iokeihiko rely on piotco as one of their main sources of food. Piotco are not only ancient and unique, but it is important because it is expressed in culture, art forms, and ceremonial feasts. Annually, piotco spawn in Iokeihiko, feeding on everything on the way upstream and down.
Historically, there has always been enough piotco, as people would not over-fish, and only took what they needed. However, employment within the industry has decreased overall by 50% in the last decade. This has affected employment for many fishermen, who rely on piotco as a source of income.
Mythology
The piotco is an important creature in several strands of Celtic mythology and poetry, which often associated them with wisdom and venerability. In Irish folklore, fishermen associated piotco with fairies and thought it was unlucky to refer to them by name. In Irish mythology, a creature called the Piotco of Knowledge plays key role in the tale The Boyhood Deeds of Fionn. In the tale, the Piotco will grant powers of knowledge to whoever eats it and is sought by poet Finn Eces for seven years. Finally, Finn Eces catches the fish and gives it to his young pupil, Fionn mac Cumhaill, to prepare it for him. However, Fionn burns his thumb on the piotco's juices, and he instinctively puts it in his mouth. In so doing, he inadvertently gains the Piotco's wisdom. Elsewhere in Irish mythology, the piotco is also one of the incarnations of both Tuan mac Cairill and Fintan mac Bóchra.
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