The Wildlife Observation Center consists of an Information Booth with displays and boardwalks leading to observation blinds for observing plant and animal communities of marshes, swamps and hardwood upland forests. Today it enjoys very healthy population sizes throughout the Refuge. Eastern Bluebirds typically nest within tree cavities created by woodpeckers and they are therefore referred to as hole or cavity nesters. The term marsh refers to any community of plants and animals that live in an area containing wet soils and lacking trees. Marshes represent an intermediate stage of the process of ecological successional that transforms an open water habitat into moist, forested land.
Marshes provide food, shelter and water for many animals such as ducks, blackbirds, and muskrats.
They act as nurseries for insects, fish, amphibians, reptiles, birds, mammals and other animals. A food web for a freshwater marsh consists of a series of interconnecting food chains. The wood duck also nests in cavities and was also an endangered species in many freshwater wetlands of the northeast not too long ago. Wood duck nesting in the Great Swamp begins in March and continues until it peaks in May and June. Unlike other ducks, wood ducks nest in tree-cavities within a half mile of suitable water.