In south-central Oregon, south-central Lake County, about 30 miles north of Lakeview, on the west side of Highway 395. At a 57-square mile surface area, Lake Abert is one of Oregon's largest lakes. It sits at the lowest part of an 860-square mile closed basin (Johnson et al. 1985). Lake Abert was designated as part of a 49,900-acre ACEC by BLM in 1996 due to the presence of prehistoric cultural values, scenic values, wildlife resources, and natural processes (aquatic ecology). It is also an ODFW Conservation Opportunity Area, and is part of a proposed Western Hemisphere Shorebird Reserve Network site (together with Summer and Goose Lakes). It has hosted peaks of >30,000 American Avocets and 150,000 phalaropes, as well as a breeding inland population of state-listed (threatened) Snowy Plovers. BLM has estimated total bird use days at 3.25 million.
Falling lake elevation in recent years has been a source of concern, with water levels falling below critical elevation according to Oregon Water Resources gauges. Lake salinity has risen beyond the upper tolerance levels of both brine shrimp and brine flies, thus resulting in greatly reduced numbers of migrating waterfowl which have historically depended on this rich food source for migration fuel. Recent bird surveys have revealed up to 80-90% decline in some cases. East Cascades Audubon Society has spearheaded seasonal waterbird surveys here.
One of only a handful of inland nest sites for Snowy Plovers in Oregon. Hosts tens of thousands of Eared Grebes, Wilson's Phalaropes, and Red-necked Phalaropes during fall migration. Hosts >1% of the Pacific Flyway population of migrant American Avocets. Over 12,000 gulls and 20,000 ducks have been recorded here.
Fluctuating water levels pose the highest threat to the health of the Lake Abert ecosystem, which may be the result of natural drought conditions or of water over-allocation.
OHV use was limited to existing roads and trails within the ACEC boundary in 1996, though may still pose limited threat along mudflats used by nesting snowy plover and other bird species. Harvesting of brine shrimp has been taking place for over 10 years with no investigation into the potential impact. Grazing was removed from public lands on the east side of the lake (from the eastern shore up to the top of Abert Rim) in the 1980's via the Paisley Agreement. Grazing on public lands was removed from the west side of the lake via completion of riparian exclosure fence in the mid-1990's. There is still some grazing on private lands on the south end and private/public lands on the north end of the lake, which may have some impact on hydrology and increase sedimentation.