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The San Luis National Wildlife Refuge Complex is managed by the U.S Fish & Wildlife Service and is composed of the San Luis National Wildlife Refuge, Merced National Wildlife Refuge, San Joaquin River National Wildlife Refuge and the Grasslands Wildlife Management Area which consists of nearly of wetlands, grasslands and riparian habitats, as well as over of conservation easements on private lands for the protection and benefit of wildlife. The refuge units are located in the northern San Joaquin Valley of California in Merced and Stanislaus Counties. The complex is headquartered in Los Banos, California and uses the Sierra National Forest Emergency Communication Center located in Fresno, California for emergency dispatch. The complex is located within the Pacific Flyway, a major route for migrating birds, including waterfowl. The extensive wetlands of the complex and surrounding lands provide habitat for up to a million waterfowl that arrive here each winter. Of the 30 species of waterfowl using the complex, the most common include Ross's geese, Aleutian cackling geese, snow geese, green-winged teal, mallards, northern pintails, gadwalls, American wigeons, northern shovelers, and greater white-fronted geese. The complex is an integral part of a mosaic of federal, state, and private lands in Merced County that together constitute the largest contiguous freshwater wetlands remaining in California. This area has been recognized as a Ramsar Wetland of International Importance, an Audubon Important Bird Area, and as a Western Hemisphere Shorebird Reserve Network site.〔(【引用サイトリンク】title=San Luis National Wildlife Refuge Complex )〕 == San Luis National Wildlife Refuge == The San Luis National Wildlife Refuge encompasses over of wetlands, riparian forests, native grasslands and vernal pools. A thriving population of tule elk is showcased by one of three auto tour routes. The refuge is host to significant assemblages of birds, mammals, reptiles, amphibians, insects and plants; some of which, such as the tiger salamander and San Joaquin kit fox, are endangered species. In 1966, the first parcel of the refuge was purchased with Federal Duck Stamp funds to provide a sanctuary for migratory waterfowl. Over the years the refuge has steadily grown in size and today it comprises six contiguous units: San Luis, East Bear Creek, West Bear Creek, Freitas, Blue Goose, and Kesterson. The San Joaquin River bisects the eastern portion of the refuge. The refuge is a major wintering ground and migratory stopover point for large concentrations of waterfowl, shorebirds and other waterbirds. Large flocks of northern shovelers, mallards, gadwalls, wigeons, green-winged teal, cinnamon teal, northern pintails, ring-billed ducks, canvasbacks, ruddy ducks, snow geese, Ross's geese, and greater white-fronted geese swarm over the mosaic of seasonal, and permanent wetlands that comprise a quarter of the refuge. Waterfowl generally remain until mid-April before beginning their journey north to breeding areas. Some mallards, gadwalls, and cinnamon teal stay through the spring and summer and breed on the refuge. Shorebirds including sandpipers and plovers can be found in the tens of thousands from autumn through spring. Large flocks of dunlin, long-billed dowitchers, least sandpipers and western sandpipers can be found feeding in shallow seasonal wetlands, whereas flocks of long-billed curlews are found using both wetlands and grasslands. Over 25 species of shorebirds have been documented at the San Luis NWR. The San Luis NWR has played a key role in the recovery of the Tule Elk, a non-migratory elk subspecies found only in California. Prior to the mid-19th century, an estimated 500,000 Tule Elk lived in California. Due to over-hunting and loss of natural habitat, they were nearly driven to extinction by the turn of the 20th century – by some accounts, the population was down to 10-20 individuals. In 1974 a herd of 18 animals was established in a large enclosure at the San Luis NWR and has since thrived. Elk from this herd are periodically relocated to establish new or join other Tule Elk herds throughout California. A true wildlife recovery success story, the statewide Tule Elk population has recovered to over 4,000 animals. Less well known are the extensive upland habitats found on the refuge. Many of these habitats are characterized by saline or alkaline conditions which are accentuated by the low rainfall and arid conditions that characterize the San Joaquin Valley. These habitats support a rich botanical community of native bunchgrasses, native and exotic annual grasses, forbs, and native shrubs. Trees, such as the valley oak, cottonwood, and willow are found along riparian corridors. In these areas, visitors might encounter coyotes, desert cottontails, ground squirrels, western meadowlarks, yellow-billed magpies, loggerhead shrikes, as well as northern harriers and white-tailed kites coursing over the vegetation and other raptors. Great blue herons, great egrets, and white-faced ibises are frequently sighted throughout the refuge. The refuge has three auto tours routes with associated nature trails and observation decks for the public to view and photograph wildlife and nature. The refuge also allows fishing at designated sites and has a large waterfowl hunting program.〔(【引用サイトリンク】title=San Luis National Wildlife Refuge )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「San Luis National Wildlife Refuge Complex」の詳細全文を読む スポンサード リンク
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