Of the tens of thousands of Canada geese flying their way northward each year, 30,000-40,000 can be viewed from the refuge, and approximately two hundred pair nest on the refuge. Iroquois National Wildlife Refuge is a stopover point on the Atlantic Flyway for waterfowl to rest and feed on their way to sting grounds in Canada. Spring waterfowl migration peaks from mid-March through early April, and other species that can be observed include American black duck, northern pintail and mallards. Fall migration peaks, generally from mid-September through early October, and visiting one of the various wetland overlooks increases your chances of viewing any of these species.

Over the years, two pairs of bald eagles have established nest sites on the refuge. Eagles start nesting behavior in January and continue until eaglets fledge in July. Eagles stay on or near the refuge for most of the year, leaving only to find open water in winter or in times of drought. When visiting Cayuga Overlook, the eagles are likely to be observed flying above. Osprey also nest on the refuge preferring similar habitat as the eagles, and are found near open water, or nesting on raised platforms. Other raptors that visitors often see include red-tailed hawks and cooper’s hawks.

The refuge’s various wetlands and marshes is ideal habitat for the muskrat. Predominantly herbivores, the species mainly consumes plant roots and stems as its diet. To provide adequate habitat for this species and others requiring similar conditions, the refuge conducts water management by manipulating water levels. Water is drawn down to low levels allowing plant seed production and high abundance of carbohydrates and re-flooded before the fall migration begins.

Emergent marsh is important to waterfowl as well as wading birds, shorebirds, songbirds, mammals, reptiles, amphibians and others. Species such black tern, bald eagle, Virginial rail, muskrat, mink and green frog all need emergent marsh for their survival. This habitat is characterized by shallow water, approximately 1-2” feet deep, with waterloving plants emerging through the surface of the water. Much of the emergent marsh in the area was long ago drained and converted to other uses. The refuge tries to restore and manage this habitat for the many species that depend on it.

The refuge contains over 3000 acres of forested wetlands (bottomland hardwoods) most of which is part of the Oak Orchard Creek floodplain. Dominant tree species include, red and silver maple, green and black ash, eastern cottonwood and American elm. These forests provide habitat for many species, including wood ducks and cerulean warblers. Species like wood ducks nest in cavities in trees, which provide them added safety from next predators. These cavities are often old holes originally excavated by woodpeckers. Cerulean warblers nest and forage high up in the tree canopies, and can usually only be heard, not seen.

While historically rare in western New York, grasslands are currently an important habitat type on the refuge. Grassland nesting birds have suffered decades of population decline, primarily due to a loss of critical habitat. The refuge maintains several large grassland areas, providing nesting and foraging habitat to these birds, which often require large unbroken grasslands for their survival. Smaller grasslands, which generally do not provide good habitat, are slowly being converted to more appropriate and useful habitat types.