Hawaiian stilt, Hawaiian coot, and black-crowned night heron are the most commonly observed native waterbirds. During the March-August nesting season of the Hawaiian stilt and coot, access must be limited to the office and parking area in order to prevent disturbance of nesting females and young of these endangered species. Fall and winter provide the best viewing, and visitors may walk cleared paths along the dikes of the old aquaculture facility to access the main body of Kealia Pond. Hawaiian duck and migratory waterfowl including northern shoveler, pintail, lesser scaup, mallard, common merganser, American and Eurasian wigeon and teal can sometimes be seen at a distance. Except for the Hawaiian duck, these birds are migrants from North America and eastern Asia.
Shorebirds seen in Hawai'i are all migrants.
They breed in Alaska, Canada, and Siberia and spend the winter in the tropics. At Kealia Pond, these birds usually forage at the outlet and mudflats on the refuge, and on adjacent beaches. These sanderlings, ruddy turnstones, wandering tattlers, Pacific golden plovers, and a variety of other coastal migrants including yellowlegs and several species of sandpipers can be seen at relatively close range during the winter months. In addition to native and migratory birds, a number seabirds and introduced species can be observed on or near the refuge. In the winter, gulls and terns that are rarely seen in Hawai'i may be found her.