Killarney shad | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Clupeiformes |
Family: | Alosidae |
Genus: | Alosa |
Species: | A. killarnensis |
Binomial name | |
Alosa killarnensis Regan, 1916 | |
The Killarney shad [2] [3] (Alosa killarnensis), also called the goureen, is a freshwater fish in the family Alosidae , endemic to a single lake in Ireland, Lough Leane in County Kerry. Research has shown that it is a landlocked subspecies of the anadromous, twait shad (Alosa fallax), arriving in the lake after the Last Glacial Maximum about 10,000 years ago. This fish is at risk from eutrophication and the introduction of alien species of fish to the lake and the International Union for Conservation of Nature has rated it as "critically endangered".
Lough Leane in the Killarney National Park, southwestern Ireland, is only the place where this fish lives. It has been listed as critically endangered by the IUCN. Eutrophication and introduction of alien fish species such as common roach Rutilus rutilus and common bream Abramis brama are the most probable threats. The shad is also very sensitive to pollution. [4]
The adopted method for conservation involves the identification of spawning sites and protecting them from declining water quality. [5]
The Killarney shad feeds in the pelagic zone of the lake and spawns in shallow bays. It has a life span of about five years. Males are smaller than the females. They generally feed on zooplankton, and spawn in June - July on gravel bars and gravelled shallows and around the islands of the lake. [2]
Most often the Killarney shad has been considered a landlocked subspecies of the anadromous, widespread twaite shad (Alosa fallax), with the name Alosa fallax killarnensis. [3] DNA-studies confirm that the population is derived from the twaite shad and suggest it arrived in the lake after the Last Glacial Maximum when the ice sheet retreated from Ireland. Moreover, there would have been another invasion wave of twaite shad to the lake, also > 10 000 yr ago, which mixed with the first one. The landlocked population has evolved many morphological and ecological peculiarities in the short post-glacial time, and therefore it has been suggested to represent an independent young species. [3] The Killarney shad is smaller than the twaite shad (only 20 cm), and has a low gill raker number. [2] [3]
While the Killarney shad is the only landlocked derivative of the twaite shad in NW Europe, several landlocked populations occur in Southern Europe, but they are not always taxonomically separated from Alosa fallax. [3]
The alewife is an anadromous species of herring found in North America. It is one of the "typical" North American shads, attributed to the subgenus Pomolobus of the genus Alosa. As an adult it is a marine species found in the northern West Atlantic Ocean, moving into estuaries before swimming upstream to breed in freshwater habitats, but some populations live entirely in fresh water. It is best known for its invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Here, its population surged, peaking between the 1950s and 1980s to the detriment of many native species of fish. In an effort to control it biologically, Pacific salmon were introduced, only partially successfully. As a marine fish, the alewife is a US National Marine Fisheries Service "Species of Concern".
The American shad is a species of anadromous clupeid fish naturally distributed on the North American coast of the North Atlantic, from Newfoundland to Florida, and as an introduced species on the North Pacific coast. The American shad is not closely related to the other North American shads. Rather, it seems to form a lineage that diverged from a common ancestor of the European taxa before these diversified.
Alosa is a genus of fish, the river herrings, in the family Alosidae. Along with other genera in the subfamily Alosinae, they are generally known as shads. They are distinct from other herrings by having a deeper body and spawning in rivers. Several species can be found on both sides of the Atlantic Ocean and the Mediterranean Sea. Also, several taxa occur in the brackish-water Caspian Sea and the Black Sea basin. Many are found in fresh water during spawning and some are only found in landlocked fresh water.
Killarney National Park, near the town of Killarney, County Kerry, was the first national park in Ireland, created when the Muckross Estate was donated to the Irish Free State in 1932. The park has since been substantially expanded and encompasses over 102.89 km2 of diverse ecology, including the Lakes of Killarney, oak and yew woodlands of international importance, and mountain peaks. It has the only red deer herd on mainland Ireland and the most extensive covering of native forest remaining in Ireland. The park is of high ecological value because of the quality, diversity, and extensiveness of many of its habitats and the wide variety of species that they accommodate, some of which are rare. The park was designated a UNESCO Biosphere Reserve in 1981. The park forms part of a Special Area of Conservation and a Special Protection Area.
Lough Leane is the largest of the three lakes of Killarney, in County Kerry. The River Laune flows from the lake into the Dingle Bay to the northwest.
The pollan or Irish pollan is a freshwater whitefish known only from five Irish lakes, Lough Neagh, Lower Lough Erne, Lough Ree, Lough Derg and Lough Allen. The pollan faces competition from introduced species such as pike, roach and zebra mussel, and the populations rely on restocking for survival.
The skipjack herring is a North American, migratory, fresh- and brackish water fish species in the herring family Alosidae. The name skipjack shad comes from the fact that it is commonly seen leaping out of the water while feeding. Other common names include blue herring, golden shad, river shad, Tennessee tarpon, and McKinley shad. The skipjack shad is restricted to the Gulf of Mexico drainage basins. Skipjack are found in clear to moderately turbid water in areas with flow. Because they are a migratory species, dams often impede their reproduction. Records suggest that this species was much more abundant in the Upper Mississippi River basin before it was impounded. Currently, skipjack is most abundant in the Upper Mississippi River below the mouth of the Ohio River. They are known as an "early-run" species as they migrate to spawn in the early spring.
The hickory shad, fall herring, mattowacca, freshwater taylor or bonejack is a member of the family Alosidae, ranging along the East Coast of the United States from Florida to the Gulf of Maine. It is an anadromous fish species, meaning that it spawns in freshwater portions of rivers, but spends most of its life at sea. It is subject to fishing, both historic and current, but it is often confused with or simply grouped together with American shad in catch statistics.
The allis shad is a widespread Northeast Atlantic species of fish in the Alosidae family. It is an anadromous fish which migrates into fresh water to spawn. It is found in the eastern Atlantic Ocean, the western Baltic Sea and the western Mediterranean Sea. In appearance it resembles an Atlantic herring but has a distinctive dark spot behind the gill cover and sometimes a row of up to six spots behind this. It sometimes hybridises with the twait shad. This fish becomes mature when three or more years old and migrates to estuaries, later swimming up rivers to spawn. Populations of this fish have declined due to overfishing, pollution and habitat destruction. Conservation of this species is covered by Appendix III of the Bern Convention and Appendix II and V of the European Community Habitats Directive.
The twait shad or twaite shad is a species of fish in the family Alosidae. It is found in the eastern Atlantic Ocean and the Mediterranean Sea and is an anadromous fish which lives in the sea but migrates into fresh water to spawn. In appearance it resembles an Atlantic herring but has a row of six to ten distinctive spots on its silvery flanks. They become mature when three or more years old and migrate to estuaries, later swimming up rivers to spawn. Populations of this fish have declined due to overfishing, pollution and habitat destruction. Conservation of this species is covered by Appendix III of the Bern Convention and Appendix II and V of the European Community Habitats Directive.
Alosa macedonica, or the Macedonian shad, is a landlocked species of alosid fish endemic to Greece. Its single natural occurrence is the freshwater Lake Volvi in northern Greece. It is threatened by habitat loss.
Alosa vistonica the Thracian shad, is a species of shad, a freshwater fish in the family Alosidae. It is endemic to a single shallow lake, Lake Vistonida in Greece. It is classified as critically endangered (CR) and is threatened by sewage, industrial effluents, destruction of spawning sites by agricultural development and increased salinity following the opening of a canal into the sea. It has been suspected to be extinct already.
Shad is a type of fish, much valued as a sport fish. The male shad is an excellent game fish, showing multiple jumps and an occasional end-over-end; it has been called a "freshwater tarpon". The gravid female does not fight much, but is often kept for the roe. The current world record is listed by the IGFA as 11 pounds 4 ounces (5.1 kg), set at Holyoke Dam, Massachusetts, on 19 May 1986 by Robert A. Thibodo.
The blueback herring, blueback shad, or summer shad is an anadromous species of herring from the east coast of North America, with a range from Nova Scotia to Florida. Blueback herring form schools and are believed to migrate offshore to overwinter near the bottom.
Alosa agone is a species of ray-finned fish in the genus Alosa. It is an endangered species.
The Pontic shad, also referred to as the Black Sea shad or Kerch shad, is a species of clupeid fish in the genus Alosa, native to the Black Sea and Sea of Azov basins.
The Alabama shad is an anadromous species of alosid fish endemic to the United States where it breeds in medium to large flowing rivers from the Mississippi River drainage to the Suwannee River, Florida, as well as some other Gulf coast drainages. The biology of this fish is little known but it has become increasingly rare. The International Union for Conservation of Nature rated it "near threatened" in 2020 and the United States National Marine Fisheries Service has listed it as a Species of Concern. A principal reason for its decline is thought to be the many locks and dams blocking access for the fish to up-river spawning grounds.
Salvelinus obtusus, commonly called the blunt-nosed Irish charr or blunt-snouted Irish char, is a species of lacustrine char fish in the family Salmonidae, found in the Lakes of Killarney, Ireland.
Salvelinus willughbii, also known as the Windermere charr or Willoughby's charr, is a cold-water fish in the family Salmonidae. Its binomial species name commemorates Francis Willughby. They are remnants from the end of the last ice-age, landlocked and isolated in various lakes within Cumbria, England. S. willughbii are a subspecies of Artic charr that inhabit Lake Windermere, Coniston Water, Wast Water, Ennerdale Water, Buttermere, Crummock Water, and Lowes Water in The Lake District of Cumbria, England.The species has been listed on the IUCN Red List as endangered due to increased water temperatures, decreased levels of oxygen, and overfishing within Lake Windermere.