Seasons of Wildlife
The Medicine Lake National Wildlife Refuge provides breeding and migration habitat for a diverse group of bird species. In fact, the refuge has been designated a Globally Important Bird Area in the United States by the American Bird Conservancy. The Refuge Complex bird list includes 283 species seen in the area since the Refuge was established.
The Refuge is central to the breeding ranges of the prairie songbirds endemic to the northern Great Plains, many of which are experiencing alarming population declines. From 1995 to 2000, the most abundant breeding songbirds in Refuge grasslands were grasshopper sparrow, Baird's sparrow, chestnut-collared longspur, and Savannah sparrow. Western meadowlarks, clay-colored sparrows, lark buntings, Sprague's pipits, and bobolinks were also common.
The importance of this area to breeding and migrating waterfowl has long been recognized and was the primary reason for the purchase of the Refuge in 1935. Most common nesting ducks are mallard, gadwall, northern pintail, northern shoveler, blue-winged teal, and lesser scaup, with a total of 14 species breeding locally. More than 300 pairs of Plains Canada geese breed in the Refuge Complex.
Spring and fall migrations bring thousands of waterfowl to the Refuge, mostly ducks, Canada and white-fronted geese, and tundra swans, with a smaller number of snow geese. Refuge wetlands provide habitat for many colonial-nesting waterbirds, including western and eared grebes, California and ring-billed gulls, double-crested cormorants, great blue herons, and American white pelicans. The large pelican colony on Big Island and Bridgerman Point has been in existence since at least 1939, and is one of the largest colonies in the United States, with about 3,000 to 5,000 nests each year.
Other marsh-nesting birds breeding in the Refuge Complex include American bittern, rails (Sora, yellow, and Virginia ), and terns (black, common, Caspian, and Forster's). A large (40-60 acre) breeding colony of Franklin's gulls is located on nearby Manning Lake, an expansive, temporary and semi-permanent wetland complex in the floodplain of Big Muddy Creek, on the Fort Peck Indian Reservation.
Thousands of migrating shorebirds are found throughout the Refuge, especially in drier years, when low water levels leave large areas of exposed shoreline. Thirty-five species of shorebirds have been observed in the Refuge, and 12 species breed there. Several upland-nesting shorebirds are common breeders in native prairie habitats: marbled godwit, willet, upland sandpiper, and Wilson's phalarope. American avocet, killdeer, spotted sandpiper, and piping plover are the most common wetland breeders.
Sharp-tailed grouse are one of the few native prairie birds that are year-round residents. They commonly breed on native prairie throughout the Refuge with about 20 leks (or “dancing grounds” for bird display and courtship behavior) located on the Refuge.
Several nonnative bird species introduced from other countries, including house sparrow, European starling, and rock dove, have spread to Montana.
Thirty-eight species of mammals have been observed in the Refuge in recent years. White-tailed jackrabbit, beaver, muskrats, and many small mammals are common. Richardson's ground squirrels are an important species, providing a prey base for other prairie species, such as ferruginous hawks and badgers, and burrows for burrowing owls and various reptiles and amphibians. White-tailed deer have increased with agricultural development and are now abundant. Mule deer and pronghorn antelope are sighted occasionally around the Refuge, and are more common in the western portions of the Refuge.
Many of the large mammals native to northeast Montana were extirpated from the area during late 1800s and early 1900s by bounty hunters and settlers. Wolves, elk, bison, swift fox, and grizzly bear were abundant in this area when the Lewis and Clark expedition traveled through in 1805. Lewis and Clark killed the first grizzly bear of their expedition 25 miles south of Medicine Lake near Culbertson, Montana. Swift fox were declared extinct in Montana in 1969, but the Refuge is within their historic range. Swift fox have been reintroduced in Saskatchewan and on the nearby Fort Peck Indian Reservation. They have re-established populations in some prairie areas, and are expanding their range. One sighting was reported in the Refuge, in northern Sheridan County in 1999.
Amphibians and Reptiles
At least 17 species of amphibians and reptiles are found within the Refuge. Tiger salamanders, northern leopard frogs, and chorus frogs are the most common amphibians. Painted turtles and garter snakes are the most common reptiles. The smooth green snake, locally common, is found nowhere else in Montana. Western hog-nosed, smooth green snakes, and northern leopard frogs are state species of special concern. While northern leopard frogs are experiencing widespread declines in other parts of Montana and North America, they remain relatively abundant in the Refuge.
More than 26 species of fish have been documented within the Big Muddy watershed of the Refuge. On the Refuge, fewer fish were present before the development of water management facilities, because wetlands periodically dried up completely. After installation of Refuge dikes and water control structures, more permanent water was maintained. Fish gained access to the Refuge water units by migrating from the Big Muddy Creek and other tributaries. Most common species were fathead minnow and carp.
Several attempts were made over the years to establish a fishery, and stocking northern pike to control large numbers of carp was successful in the late 1960s. An exceptional northern pike fishery developed in Medicine Lake, and the Refuge became well-known. However, little reproduction occurred, and restocking was required annually. The fishery was eliminated during the drought of the late 1980s and early 1990s due to low water levels and winter-kill.
The return of high water flows in 1993 and 1994 again brought forage fish back into the Refuge. White pelicans, great blue herons, grebes, and other birds feed extensively on these fish. Stocking of northern pike resumed in 1996, and the northern pike fishery is again well-established at Medicine Lake. Few, if any, fish inhabit wetlands in waterfowl production areas, since the basins are not deep enough for fish to survive the winter.
The diversity of invertebrates in the Refuge has not been well-quantified, though they are an extremely important component of the ecosystem. Refuge wetlands produce huge numbers of invertebrates such as midges, dragonflies, amphipods, copepods, and water boatmen. Prairies and other grasslands produce large numbers of insects (notably grasshoppers, leafhoppers, butterflies, beetles), and spiders. These invertebrates are the food base for nearly all breeding bird species. Two butterfly species of special concern, Ottoe skipper and tawny crescent, have been collected in the Refuge.
Medicine Lake National Wildlife Refuge is home to a variety of wildlife. From birds and mammals to fish and invertebrates, the Refuge provides shelter and food for many species including the grasshopper sparrow, bobolink, beaver, muskrat, tiger salamander, leopard frog, northern pike, and Ottoe skipper butterfly.