The Global 200 : a representation Approach to Conserving the Earth’s Distinctive Ecoregions
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NearcticS outheastern Rivers and Streams[175] – United States Geographic Location: Southeastern North America Biodiversity Features: This large region, covering nearly 10 percent of the United States, holds some of the most species-rich coastal river ecosystems in the world. Within the Roanoke River basin alone, more than 200 fish species are found, of which six are endemic. Other highly diverse aquatic groups include bivalves, snails, and crayfish. One of few natural lakes in the Southeast United States, Lake Waccamaw was likely formed by a meteoric impact and harbors several endemic fish—a highly unusual evolutionary phenomenon. ONE OF THE MOST DIVERSE COASTAL RIVER ECOREGIONS, WITH HIGH richness and endemism OF FISH AND FRESHWATER INVERTEBRATEs Selected Species: Fish species include local endemics such as Waccamaw silverside (Menidia extensa), Waccamaw killifish (Fundulus waccamensis), and Waccamaw darter (Etheostoma perlongum). Numerous other fishes found in the ecoregions streams include cyprinids (e.g, fieryback shiner (Cyprinella pyrrohmela), redlip shiner (Notropis chiliticus), blackmouth shiner (Notropis melanostomus), blacktip shiner (Lythrurus atrapiculus)), darters (e.g., Choctawhatchee darter (E. davisoni), southern logperch (Percina autroperca), Florida sand darter (Etheostoma bifascia), Okaloosa darter (E. okaloosae)), suckers (e.g., greater jumprock (Moxostoma lachneri), grayfin redhorse (Moxostoma sp.)), and larger species like alligator gar (Atractosteus spatula). Aquatic species other than fish include Mabee’s salamander (Ambystoma mabeei), dwarf waterdog (Necturus punctatus), Neuse River waterdog (N. lewisi), ringed map turtle (Graptemys oculifera), Everglades crayfish (Procambarus alleni), and Florida applesnail (Pomacea paludosa). General Threats: This ecoregion is in one of the most highly populated areas in the United States, and it is rapidly growing. Despite the fact that this is a well-watered region, humans are competing with aquatic species for water. Interbasin water transfers and dams are prevalent, and new projects are planned. Aquatic habitats are further modified through widespread channelization. Pollution from acid rain, deforestation, roads, agriculture, urbanization, and industrialization places additional stresses on native species. Introduction of nonnative species like Asiatic clam (Corbicula fluminea) and zebra mussel (Dreissena polymorpha) threaten native mussel populations, and exotic fish pose similar threats to native fish.
acific Northwest Coastal Rivers and Streams [176] – United States Geographic Location: Northwest coast of North America Biodiversity Features: The rivers and streams of the northwestern United States, specifically the Sacramento/San Joaquin River basin in the Central Valley of California, the Klamath River basin, and coastal streams and rivers of Oregon, contain many endemic species. These rivers also support large numbers of migratory fish that ascend from the ocean to freshwater environments to spawn. DISTINGUISHED BY LARGE-SCALE MIGRATIONS OF ANADROMOUS FISH, CONTAINS NUMEROUS endemic FRESHWATER SPECIES Selected Species: The most prominent migrating species are salmon, including pink (Oncorhynchus gorbuscha), chum (O. keta), chinook (O. tshawytscha), coho (O. kisutch), and sockeye (O. nerka). Other migrating fish include multiple species of trout, lamprey, sturgeon, sculpin, and stickleback. Some of the endemic fish species are Pit-Klamath brook lamprey (Lampetra lethophaga), western brook lamprey (L. richardsoni), white sturgeon (Acipenser transmontanus), Sacramento blackfish (Orthodon microlepidontus), Klamath smallscale sucker (Catostomus rimiculus), and Sacramento squawfish (Ptychocheilus grandis). Endemic invertebrates include Shasta crayfish (Pacifastacus fortis) and endemic syncarid shrimp species (Syncaris spp.) General Threats: Clear-cut logging causes severe damage to these freshwater systems, through siltation, increased water temperatures, and altered flow regimes. Introduced species threaten native fish and invertebrates; of the present-day fish fauna in the region, nearly 40 percent may be introduced species, most from eastern North America. Other threats include water diversion and impoundment, which, among other effects, disrupt fish migration routes. In addition, there is growing concern that warming ocean temperatures may adversely affect migrating salmonids during the oceanic portion of their life cycle. In some areas, overfishing is also a problem.
ulf of Alaska Coastal Rivers and Streams [177] – Canada, United States Geographic Location: Upper western coast of North America, including Kodiak Island, the Alexander Archipelago, Vancouver Island and the Queen Charlotte Islands Biodiversity Features: This ecoregion is particularly important for its high concentrations of anadromous fish. These species serve as keystone elements by transferring marine-derived nutrients to the freshwater realm on an annual basis. Parts of this ecoregion escaped glaciation and harbor localized endemics, particularly among cave-dwelling invertebrates. ONE OF MOST IMPORTANT regions for ANADROMOUS FISH SPAWNING RUNS Selected Species: Species include Arctic lamprey (Lampetra japonica), broad whitefish (Coregonus nasus), Alaska whitefish (C. nelsoni), Arctic cisco (C. autumnalis), Angayukaksurak char (Salvelinus anaktuvukensis), and numerous anadromous salmon (Oncorhynchus tshawytscha, O. nerka, O. mykiss, O. gorbuscha, O. keta, and O. kisutch). Endemic fish found here are Olympic mudminnow (Novumbra hubbsi) and Salish sucker (Catostomus sp.). General Threats: Sedimentation from clear-cut logging, development near urban areas, and expanding agriculture pollutes some of the rivers and streams in this area, although large portions of the ecoregion are in areas with few people. Oil spills, pipelines, dams, and overfishing are other threats to the migrating fish and other species of this region. Destructive logging practices are the largest and most extensive threat. In addition, there is growing concern that warming ocean temperatures may adversely affect migrating salmonids during the oceanic portion of their life cycle. Neotropical
uianan Freshwater [178] – Brazil, French Guiana (France), Guyana, Suriname, Venezuela Geogrpahic Location – northeastern South America Biodiversity Features: The coastal rivers of this ecoregion drain the Guyana Shield and contain a wide range of flowing water habitats—cataracts, rapids, and riparian flooded forests, among others. Though poorly investigated, these rivers are known to support a very diverse, highly intact, and notably endemic freshwater fauna. In many rivers, local endemism is the result of isolating waterfalls. INTACT FRESHWATER FAUNA EXHIBITING HIGH DEGREE OF ENDEMISM Selected Species: Among the numerous species found in this important freshwater system are the imperiled arapaima (Arapaima gigas), giant South American river turtle (Podocnemis expansa), black caiman (Melanosuchus niger), and arowana (Osteoglossum bicirrhosum). This ecoregion provides some of the best remaining habitat for giant river otter (Pteronura brasiliensis). General Threats: The freshwater habitats of this ecoregion remain relatively intact and support a generally stable freshwater biota. However, valuable game species, such as the enormous arapaima and some reptiles, are imperiled as a result of overexploitation and an illegal border trade. Deforestation, as a result of logging, fuelwood harvest, mining, and agriculture, has led to erosion, sedimentation, and altered hydrologic regimes. Extraction of trees for telephone and electricity poles is also a serious problem in certain forest types, and many wildfires have resulted from charcoal and agricultural production. Agricultural activities contribute pesticides to the ecoregion’s waters, and industrial and domestic wastes have polluted much of the water on the coastal plain. Gold and bauxite mining are important activities in this ecoregion, and a series of cyanide spills linked to gold mining activities signals a continuing threat in this ecoregion. Finally, water extraction may become a problem, even in this well-watered area.
reater Antillean Freshwater [179] – Cuba, Dominican Republic, Haiti, Puerto Rico (United States). Geographic Location: Caribbean Biodiversity Features: Unlike the fauna of most island freshwater streams, the species found in Greater Antillean streams are generally not derived from marine organisms, but are more closely related to continental forms. This ecoregion has a high degree of endemism, with at least 70 species of native freshwater fishes, many of which are restricted to individual river basins. The family Poecillidae, with five genera and over 40 fish species, dominates the fish fauna. Seven species of freshwater crabs from one genus are endemic to Cuba. Karstic systems are a largely unexplored habitat type on these islands and will likely result in the discovery of more endemic freshwater species. UNUSUAL FRESHWATER FORMS DErived FROM CONTINENTAL ANCESTORS, INCLUDING ENDEMIC FISH AND CRABS Selected Species: Characteristic native Antillean freshwater fishes include Cuban gar (Attractosteus tristoechus), Hispaniolan gambusia (Gambusia hispaniolae), green rivulus (Rivuluscylindraceus), and Hispaniola pupfish (Cyprinodon bondi). The most threatened New World crocodile, Crocodylus rhombifer, survives in the Zapata Swamp, a located in southwestern Cuba. The widespread American crocodile (Crocodylus acutus) also occurs in this ecoregion. General Threats: Clearing of forests and conversion of land to agriculture are major threats to the integrity of the freshwater systems of the islands. Growing human populations put pressure on these freshwater systems through discharge of untreated sewage and other pollutants resulting from urban development. Introduction of exotic species, particularly tilapia (Oreochromis mossambicus), have been detrimental to native fish populations. Palearctic
alkan Rivers and Streams [180] – Albania, Bosnia and Herzogovina, Bulgaria, Croatia, Greece, Macedonia, Turkey, Yugoslavia Geographic Location: Southeastern Europe Biodiversity Features:Much of southern Europe escaped recent glaciation, thus diversity within drainages tends to be higher than in northern Europe. In addition to escaping glaciation the Balkans contain extensive areas of karst topography that support an endemic troglobitic freshwater biota. The Balkans region hosts an extremely diverse and highly endemic gastropod fauna, with about 200 known species. For example, the Sava River alone harbors 103 gastropod species, of which 54 are endemic. Many endemic fish species and genera are also present in the ecoregion. DISTINCTIVE EUROPEAN FISH AND MOLLUSC FAUNA WITH RELATIVELY HIGH LEVELS OF REGIONAL AND LOCAL ENDEMISM Selected Species: Restricted mainly to the Dalmatian karst area of Bosnia-Herzogovina, the highly endangered Dalmatian barbel gudgeon (Aulopyge hügeli) inhabits both above-ground rivers and subterranean karst rivers. Subterranean watercourses in the ecoregion also support populations of the highly endangered and endemic olm, or blind salamander (Proteus anguinus), as well as many endemic invertebrates. Endemic trout live in the rivers and lakes of this ecoregion, including Ohrid (Salmo letnica), marbled (Salmo marmoratus), and belushka (Acantholingua ohridana) trouts, as well as S. dentex. The ecoregion is home to a number of other endemic and rare fishes, many of which are vulnerable, endangered, or even critically endangered. Among these species are Greek brook lamprey (Eudontomyzon hellenicus), Leuciscus illyricus, and Phoxinellus ghetaldii. General Threats: The aftermath of recent conflicts in this region includes large-scale movements of refugees across the region and pollution and fires originating from bombed industrial sources. Runoff of agricultural chemicals and industrial waste, as well as untreated sewage effluents, also pollute the waterways in many parts of this ecoregion. Dams have altered the hydrology of many of the rivers in this region and planned projects are expected to continue to drastically change the environments in which many native species have evolved. There is great concern about the ability of the many localized endemics to survive these changes. The ecoregion also includes a large number of introduced species that are believed to negatively impact native species. For example, hybridization of the rare marbled trout, Salmo marmoratus, with introduced brown trout, S. trutta, has reduced the genetic integrity of the native species.
ussian Far East Rivers and Wetlands [181] – China, Mongolia, Russia Geographic Location: Eastern coast of north Asia Biodiversity Features: Headwater streams, floodplain lakes, deltas, and highland lakes are among the diversity of habitats represented in this ecoregion. The ecoregion supports a high fish diversity and globally outstanding populations of salmon and sturgeon. The Amur River supports more fish species than any other Russian river with over 120 species. Molluscs and crustaceans are especially diverse, comprising a special Far East complex. Of the molluscs, approximately a dozen species may face extinction. This ecoregion also contains some of Asia’s most extensive temperate reedbeds and wet meadows. These wetlands support a rich bird fauna, including endangered cranes, along with some endemic and rare plant species. one of the richest freshwater ecoregions in eurasia, PARTICULARLY FOR FISH SPECIES, ancient river systems Selected Species: Sturgeons and migratory salmon include Amur (Acipenser schrenckii), Sakhalin (A. mikadoi), and kaluga (Huso dauricus) sturgeon, and chum (Oncorhynchus keta) and pink (O. gorbuscha) salmon. The threatened red-crowned (Grus japonensis) and white-naped (G. vipio) cranes are protected in wetland reserves adjacent to the Amur River. Other inhabitants include soft-skinned Far Eastern turtle (Amyda sinensis), Ussuri soft-shelled turtle (Trionyx sinensis), Amur pike (Esox reichertii), Amur whitefish (Coregonus ussuriensis), the mussel, Middendorffinaia ussuriensis, and long-tailed clawed salamander (Onychodactylus fischeri). General Threats: Fishing pressure in parts of this ecoregion is intense, including poaching of salmon on breeding grounds for roe and driftnetting for salmon in international waters. Oil and gas drilling threaten fish habitat through dumping of drilling muds and the potential of oil spills. Heavy metal loading of waterways is occurring due to mining in the region. Logging of surrounding forests also places stress on the rivers and streams of this region, as riparian buffers are logged and sedimentation increases. Directory: downloads downloads -> Northern England’s set-jetting locations downloads -> Dynatest 3031 lwd light Weight Deflectometer downloads -> Forth coming competitive exams downloads -> Brush High School Morning Announcements Friday, September 05, 2014 all school downloads -> Year 9 The Arts — Music downloads -> Years 7 and 8 standard elaborations — Australian Curriculum: Music draft downloads -> Chris Young sets 2016 “I’m Comin’ Over” Tour headlining dates downloads -> Slavery and Abolition: the Plymouth Connection Introduction downloads -> Summer Assignment Download 2.75 Mb. Share with your friends:
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