Located on the Mississippi Flyway, Minnesota hosts migratory waterfowl such as geese and ducks, and game birds such as grouse, pheasants, and turkeys. It is home to the largest population of bald eagles in the contiguous United States following a large increase in conservation efforts and breeding areas since 1989, with an estimated 30 active nests in the Twin Cities alone. The red-tailed hawk thrives in Minnesota woodlands, swamps, and prairies, where rodent populations are high. Although they do not nest in the state, snowy owls migrate to Minnesota from the arctic tundra to hunt voles, mice, and rabbits. The number of snowy owls in the state in any given winter depends greatly on the winter conditions of the snowy owl's natural habitat, in areas such as Canada and Alaska.