Today, the Summer Lake Wildlife Area supports 40 mammal species, at least 280 species of birds, 15 reptile and amphibian species, and eight fish species.
 The wildlife area provides habitat for aquatic mammals like beaver and muskrats.
 The area also supports non-aquatic animals such as Nuttall's cottontail, black-tailed jackrabbits, yellow-bellied marmot, chipmunks, Belding's ground squirrels, California ground squirrels, long-tailed weasels, mink, raccoons, striped skunks, mule deer, coyotes, and bobcats.
 There are also three bat species which live in the Summer Lake area.

The various Summer Lake habitats supports a diverse population of upland game birds, songbirds, shorebirds, waterfowl, and birds of prey.
In the dry high desert country at the north end of the wildlife area, California quail and mourning doves are common.
 There is also a small breeding population of ring-necked pheasants along with greater sage grouse and chukars.
 Songbirds common to that area include Bullock's orioles, sage thrashers, canyon wrens, rock wrens, and sagebrush sparrows.
 Songbirds commonly found in the marshy areas of the lower Ana River include Brewer's sparrows, lark sparrows, marsh wrens, red-winged blackbirds, and yellow-headed blackbirds.

Numerous shorebirds nest in the Summer Lake Wildlife Area.
 These include American avocets, black-necked stilts, western snowy plovers, spotted sandpipers, Wilson's phalaropes, Wilson's snipes, long-billed curlews, western willets, and killdeer.
Sandhill cranes, great egrets, snowy egrets, black-crowned night herons, white-faced ibis, double-crested cormorants, Caspian terns, American white pelicans, and Forster's terns also nest in the Summer Lake wetlands.
 The wildlife area hosts large nesting populations of waterfowl including Canada geese, mallards, cinnamon teal, blue-winged teal, gadwalls, American coots, and redhead ducks.
 Additional bird species stop in the Summer Lake Wildlife Area during their spring and fall migrations.
 These include trumpeter swans, tundra swans, snow geese, greater white-fronted geese, long-billed dowitchers, Baird's sandpipers, red-necked phalaropes, and dunlins.

Because of the large numbers birds found in the Summer Lake basin, birds of prey are common.
Native owls include great horned owls, barn owls, and short-eared owls.
Prairie falcons, American kestrels, red-tailed hawks, Cooper's hawks, Swainson's hawk, golden eagles, and bald eagles are also found in the Summer Lake area.

The Ana River has stocked populations of hybrid striped bass and rainbow trout as well native Summer Lake tui chub and non-native Goose Lake tui chub.
 The river's tui chub range in size from less than an inch to about ten inches in length.
 Both species of tui chub are found throughout the Anna River system and provide an important food source for a wide variety of mammals and birds as well as other fish.
 Oregon Department of Fish and Wildlife stocks the river with approximately 2,000 hybrid bass fingerings every two years.
 Like the bass population, all of the river's rainbow trout are stocked.
 While the river has been stocked with up to 20,000 trout every year since the early 1940s, there is no evidence of trout spawning in any part of the river.
Today, the Summer Lake Wildlife Area supports 40 mammal species, at least 280 species of birds, 15 reptile and amphibian species, and eight fish species.  The wildlife area provides habitat for aquatic mammals like beaver and muskrats.  The area also supports non-aquatic animals such as Nuttall's cottontail, black-tailed jackrabbits, yellow-bellied marmot, chipmunks, Belding's ground squirrels, California ground squirrels, long-tailed weasels, mink, raccoons, striped skunks, mule deer, coyotes, and bobcats.  There are also three bat species which live in the Summer Lake area.
The various Summer Lake habitats supports a diverse population of upland game birds, songbirds, shorebirds, waterfowl, and birds of prey. In the dry high desert country at the north end of the wildlife area, California quail and mourning doves are common.  There is also a small breeding population of ring-necked pheasants along with greater sage grouse and chukars.  Songbirds common to that area include Bullock's orioles, sage thrashers, canyon wrens, rock wrens, and sagebrush sparrows.  Songbirds commonly found in the marshy areas of the lower Ana River include Brewer's sparrows, lark sparrows, marsh wrens, red-winged blackbirds, and yellow-headed blackbirds.
Numerous shorebirds nest in the Summer Lake Wildlife Area.  These include American avocets, black-necked stilts, western snowy plovers, spotted sandpipers, Wilson's phalaropes, Wilson's snipes, long-billed curlews, western willets, and killdeer. Sandhill cranes, great egrets, snowy egrets, black-crowned night herons, white-faced ibis, double-crested cormorants, Caspian terns, American white pelicans, and Forster's terns also nest in the Summer Lake wetlands.  The wildlife area hosts large nesting populations of waterfowl including Canada geese, mallards, cinnamon teal, blue-winged teal, gadwalls, American coots, and redhead ducks.  Additional bird species stop in the Summer Lake Wildlife Area during their spring and fall migrations.  These include trumpeter swans, tundra swans, snow geese, greater white-fronted geese, long-billed dowitchers, Baird's sandpipers, red-necked phalaropes, and dunlins.
Because of the large numbers birds found in the Summer Lake basin, birds of prey are common. Native owls include great horned owls, barn owls, and short-eared owls. Prairie falcons, American kestrels, red-tailed hawks, Cooper's hawks, Swainson's hawk, golden eagles, and bald eagles are also found in the Summer Lake area.
The Ana River has stocked populations of hybrid striped bass and rainbow trout as well native Summer Lake tui chub and non-native Goose Lake tui chub.  The river's tui chub range in size from less than an inch to about ten inches in length.  Both species of tui chub are found throughout the Anna River system and provide an important food source for a wide variety of mammals and birds as well as other fish.  Oregon Department of Fish and Wildlife stocks the river with approximately 2,000 hybrid bass fingerings every two years.  Like the bass population, all of the river's rainbow trout are stocked.  While the river has been stocked with up to 20,000 trout every year since the early 1940s, there is no evidence of trout spawning in any part of the river.
Summer Lake Wildlife Area