Tetlin Refuge has a comprehensive landbird monitoring program that is consistent with the International Partners in Flight Initiative. This includes maintaining migratory bird arrival dates, participating in the North American Migration Count, Breeding Bird Surveys, off-road point counts and fall migration banding. In addition, a Christmas Bird Count is conducted each winter and an Upper Tanana Bird Festival is hosted by the Refuge in mid-May.
Four Breeding Bird Surveys (BBS) routes in eastern interior Alaska are completed annually. Off-road point counts were established on the Refuge in 1994 as part of a pilot project for Boreal Partners in Flight. Seven routes are monitored each year as part of the Alaska Landbird Monitoring System (ALMS).
A fall migration banding station was established in 1993 seven miles east of Tok and has been operated daily in August and September each year. This long-term banding effort is part of a regional landbird monitoring program and helps to monitor landbird populations not adequately monitored by the Breeding Bird Survey. The most common species captured are: slate-colored junco, Swainson’s thrush, Wilson’s warbler, ruby-crowned kinglet, Myrtle (yellow-rumped) warbler, and orange-crowned warbler.
Only 30 species of birds are residents on the Refuge. Gray jay, black-billed magpie, common raven, black-capped chickadee, boreal chickadee, and redpolls are the most common species with lesser numbers of the non-migratory owls and woodpeckers. White-winged crossbills are abundant during productive cone crop years. Spruce grouse, ruffed grouse, sharp-tailed grouse, and willow ptarmigan are uncommon breeders on the Refuge. Sharp-tailed grouse have increased, especially in the Tok and Tetlin Village areas following the Tok River Fire in 1990.
Thirteen species of hawks are known to occur on Tetlin Refuge. Usually present in small numbers, bald eagle, osprey, northern harrier, sharp-shinned hawk, red-tailed hawk, and American kestrel are confirmed breeders. Less frequently observed northern goshawk, golden eagle, merlin, peregrine falcon, and gyrfalcon are rare breeders on the Refuge. Rough-legged hawks are uncommon migrants. Turkey vultures and Swainson’s hawks are casual visitors.
Six species of owls occur on the Refuge, the most common being the great horned owl. Northern hawk owls, great gray owls, and boreal owls can be fairly common some years. The short-eared owl is a migrant and casual summer breeder, while the snowy owl is a casual visitor in fall and winter.
The American peregrine falcon is the only previously endangered species found on the Refuge. The population of this species/race has been increasing nation-wide and was de-listed in 1999. The first peregrine falcon nest on Tetlin Refuge was discovered in June 1994 along the Nabesna River nearly 100 river miles upstream from the closest known nest site. Recovering peregrine populations have increased their density within their nesting range in the Upper Tanana Valley in the last decade, doubling the number of territories in the last decade to 22 presently known above the Robertson River.
Extensive raptor surveys have been completed annually since 1991. Most raptor nests are located along the rivers, lakes and wetlands.
Green-winged teal, mallard, American wigeon, ring-necked duck, lesser scaup and bufflehead are the most abundant ducks breeding on the Refuge.Smaller numbers of northern pintail, northern shoveler, Barrow’s goldeneye, common goldeneye, white-winged scoter, surf scoter, canvasback and blue-winged teal are known to breed here as well. Rare sightings are made of common mergansers, redheads, ruddy ducks, gadwall and harlequin ducks which also breed in the area, or of long-tailed ducks which do not. An estimated 35,000 to 65,000 ducklings are produced on Tetlin Refuge each year.
The Refuge lies along an important migration route for both Canada and greater white-fronted geese that migrate to and from the state. Occasionally snow geese and brant are seen during migration. Canada geese breed on the refuge in small numbers.
The Refuge provides important habitat for migrating tundra and trumpeter swans during spring and fall. Over 200 trumpeter swan cygnets in the refuge area were banded and neck collared from 1983 to 1984 and from 1989 to 1995. Recoveries and sightings of banded trumpeter swans help identify their wintering habitat as being coastal wetlands and fields from the central coast of British Columbia to northern Puget Sound.
Nine species of marsh and water birds occur on the Refuge with horned grebe, pacific loon, and red-necked grebe being the most common breeders. Common loons are rare breeders and red-throated loons are considered casual. A small number of sandhill cranes nest on the muskeg flats in the northern third of the refuge. During spring and fall migration, up to 200,000 sandhill cranes (one half of the entire world population) can pass through the Tanana River Valley. The numbers seen from year to year vary depending on weather conditions which affect their flight paths. The Upper Tanana Valley is one of the few places in Alaska where sora and American coot are found.
While some 26 species of shorebirds occur on the Refuge, most are migrants passing between wintering and breeding grounds. The most abundant breeding shorebird is the ubiquitous lesser yellowlegs. Common snipe are less abundant but widely distributed, while spotted sandpipers are common along watercourses. Red-necked phalaropes are often seen during fall migration. Mew and Bonaparte's gulls are common breeders. The American golden plover, upland sandpiper, and whimbrel breed in the alpine areas