Knee-high waders are usually necessary to walk the dirt track to Nelson Island; without them, you must pay attention to the tides and plan to return to the parking lot well before high tide. There are no facilities, and dogs are prohibited at all times on Nelson Island. 

The salt marsh from late March to November is a feeding ground for the complete range of herons, egrets, and glossy ibises that summer in New England, especially at high tide when they can’t hide in the ditches. This is when they concentrate in the salt pans, some of which lie right beside the dirt track between the parking lot and Nelson Island. Shorebirds of many species also feed in these pans, while gulls, terns, and kingfishers course the surrounding marshes. Nesting marsh species are willets, killdeer, saltmarsh sharp-tailed sparrows, and occasional seaside sparrows. The hayfield has nesting bobolinks and sometimes eastern meadowlarks and savannah sparrows. The fringes of the island feature nesting orchard orioles and willow flycatchers–maybe one or two pairs of each. This is one of the best places in the county to find orchard orioles. Winter highlights are the raptors: short-eared and snowy owls, northern harriers, red-tailed and rough-legged hawks, and occasional bald eagles. Horned larks, snow buntings, and Lapland longspurs may also be found on the island in winter.

Nelson Island is a small island located within the Parker River National Wildlife Refuge. The Nelson Island section of the refuge is accessible by foot only via a 0.8-mile gravel trail. The island was once home to a fishing community and a Coast Guard station. Today, it is a habitat for various wildlife species, such as shorebirds, waterfowl, seals, and turtles. Nelson Island is open to the public from April to October. 

Access is via Stackyard Road. Rowley lies between Newbury and Ipswich. From the center of Rowley at the traffic light on MA-1A, drive north on MA-1A about 2 miles to a dirt road on the right marked Stackyard Road. Take this road and keep to the right when it forks. Follow to the end, about a mile from 1A, and park in the Parker River National Wildlife Refuge parking lot. (The refuge has much land on the west side of the marsh as well as Plum Island.) From here you can walk the dirt track out to Nelson Island, or back along the road to explore the marsh edges.

Located along the northeast coast of Massachusetts, Parker River National Wildlife Refuge was established in 1941 to provide a feeding, resting, and nesting habitat for migratory birds. Most commonly associated with Plum Island, a barrier beach island, the refuge is comprised of more than 4700 acres of diverse habitats including sandy beach and dune, cranberry bog, maritime forest and shrubland, and freshwater marsh. The most abundant habitat on the refuge is its 3,000+ acres of salt marsh, one of the most productive ecosystems in nature. Parker River provides a pristine coastal habitat for over 300 species of resident and migratory birds, as well as a large variety of mammals, insects, fish, reptiles, and amphibians. The refuge also provides critical habitat for the federally threatened piping plover.

In addition to its mission of wildlife conservation, the refuge provides a variety of excellent wildlife-dependent recreational activities, including surf fishing, wildlife observation and photography, a variety of interpretive programs, and seasonal waterfowl and deer hunting opportunities. A large visitor center, complete with a classroom and auditorium, msupports many of these public uses.

Parker River has achieved the following special designations: Western Hemispheric Shorebird Reserve Network (WHSRN), Important Bird Area (IBA), and Area of Critical Environmental Concern (ACEC).