In south-central Oregon along Highway 31, west-central Lake County. Summer Lake is a classic closed-basin playa; however, it is unusually supplied by the spring-fed Ana River. The north end of the lake includes extensive impounded wetlands, while the southern playa offers extensive mudflats (when water is present) in late summer for migrating shorebirds.
Summer Lake is an important area for Snowy Plover, hosting a significant percentage of Oregon's inland population. During fall migration, in years when water is present on the playa, incredible numbers of American Avocet, ranging from 30,000-50,000 (D. Tracy pers. comm., Paulson 1993) gather on Summer Lake's mudflats. One of the few regional locations where Black-Crowned Night-Herons breed and roost. Summer Lake WMA, managed by ODFW, hosts thousands of wintering and migrating waterfowl.