Alvord Lake is a seasonal shallow alkali lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

 in Harney County

Harney County, Oregon

-National protected areas:*Malheur National Forest *Malheur National Wildlife Refuge*Ochoco National Forest -Demographics:As of the census of 2000, there were 7,609 people, 3,036 households, and 2,094 families residing in the county. The population density was 1 people per square mile...

 of the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

. Its elevation is 4026 feet (1,227.1 m). It is located about 10 miles (16.1 km) southeast of Alvord Desert

Alvord Desert

The Alvord Desert is a desert located in Harney County, in southeastern Oregon in the western United States. It is roughly southeast of Steens Mountain. The Alvord Desert is a dry lake bed and averages of rain a year. Two mountain ranges separate it from the Pacific Ocean—the Coast Range, and...

 in the Alvord Basin and serves as terminus for all its streams. Its water level varies from dry to several feet deep. The nearest habitation is tiny Fields

Fields, Oregon

Fields is a small unincorporated community in Harney County, Oregon, United States, located south of Burns.In 2000, the community had a population of 86, including 17 students through grade 8. The average age was 38; the average household size was 2.53 persons; the average household income was...

, 14.1 kilometres (8.8 mi) SSW.

At one time, Alvord Lake stretched 100 miles (160.9 km) along the east side of Steens Mountain.

The Alvord Basin covers about 2150 mi2 bounded on the northwest by Steens Mountain

Steens Mountain

Steens Mountain is a large fault-block mountain in the southeastern part of the U.S. state of Oregon. Located in Harney County, it stretches some and rises from an elevation of about above the Alvord Desert to its peak at...

, on the southwest by the Pueblo Mountains

Pueblo Mountains

The Pueblo Mountains are a remote mountain range in the United States located in southeastern Oregon and northwestern Nevada. The highest point in the range is Pueblo Mountain. The dominant vegetation throughout the range are grasses and sagebrush; however, there are meadows with cottonwood,...

, on the southeast by the Trout Creek Mountains

Trout Creek Mountains

The Trout Creek Mountains are a remote mountain range in southeastern Oregon and northern Nevada, United States. The highest point in the range is Orevada View Benchmark. Most of the Trout Creek Mountains are public lands, administered by the Bureau of Land Management. There is very little human...

, and on the northeast by the Sheepshead Mountains

Sheepshead Mountains

The Sheepshead Mountains are a mountain range in Malheur County, Oregon....

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Major tributaries are Mosquito Creek, Willow Creek, Wildhorse Creek, Whitehorse Creek, Trout Creek, and Van Horn Creek.

The tributaries of Alvord Lake were home to the endemic Alvord cutthroat trout

Alvord cutthroat trout

The Alvord cutthroat trout, Oncorhynchus clarki alvordensis, was a subspecies of cutthroat trout. It was native to spring-fed creeks that ran down to Alvord Dry Lake in southeast Oregon, which was a large lake during the ice ages and an isolated drainage, part of the Great Basin today...

, which is now considered extinct

Extinction

In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 through hybridization with non-native rainbow trout

Rainbow trout

The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....

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