A mud hen wades in the shallows of the water's edge at NASA's Kennedy Space Center in Florida.

A mud hen wades in the shallows of the water's edge at NASA's Kennedy Space Center in Florida.

The center shares a boundary with the Merritt Island National Wildlife Refuge, consisting of 140,000 acres. The refuge provides a wide variety of habitats -- coastal dunes, saltwater estuaries and marshes, freshwater impoundments, scrub, pine flatwoods, and hardwood hammocks -- that provide sanctuary for more than 1,500 species of plants and animals, including about 331 species of birds. Photo credit: NASA/Jim Grossmann