Places We Protect

Sagg Swamp Preserve

New York

A boardwalk runs through a densely wooded area.
Sagg Swamp Preserve Boardwalk at TNC's Sagg Swamp Preserve on Long Island. © A. Graziano Photography

A jewel at the southern end of the Long Pond Greenbelt.



At the center of the preserve, the freshwater stream that bisects the wild swamp and tangled woodland are impounded by a weir. On the downstream side, it becomes a shallow, bubbling rill, while the upper section widens out into acres of open picturesque swampland, with stunted red maples and carpets of sphagnum moss.

Like many natural areas on Long Island, Sagg Swamp has a long and interesting history of human use. From the 1600s to the 1800s, various gristmills, where grain was pounded into flour, and fulling mills, where cloth makers cleaned and thickened wool, were constructed and operated with limited success near the bridge on Sagaponack Road. There was even a brewery on the banks of the stream. When the last of these attempts failed around 1850, the area returned to swampland.




105 acres

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Sagg Swamp is a great destination for botanists and birding. The mostly level trail and boardwalk traversing the swamp make it a good place for family nature outings. Encompassing more than 105 acres, Sagg Swamp is easily the largest and most diverse red maple swamp on the South Fork of Long Island. The preserve trail loops around through the southern part of the swamp via a long stretch of boardwalk that provides a close-up look at a fascinating habitat that would otherwise be inaccessible without hip boots.

The plant diversity of the preserve is remarkable, with more than 330 species, including a particularly rich variety of ferns. Red maple, tupelo, wild azaleas and a variety of other moisture-loving shrubs, wildflowers, and ferns dominate the lower, wetter sites while pockets of oak woodland occupy the higher ground. These, plus three stands of Atlantic white cedar, now exceedingly rare on Long Island, make this a paradise for plant lovers.

Sagg Swamp is also a great destination for birders. The preserve is a locally important nesting area for the black-crowned night heron, just one of the 84 bird species that have been recorded here. Its north-south expanse also makes Sagg Swamp important stopover habitat for migrating birds. Jeremy’s Hole, a peaceful pool north of the trail, is a critical sanctuary for a great abundance and variety of waterfowl, particularly during migration. Among the preserve’s other wild denizens are muskrats, a number of locally rare turtles and salamanders, and flying squirrels. American eels and alewives live in the freshwater streams and ponds.

The fragrant white and pink, trumpet-shaped flowers of swamp and pinxterbloom azaleas, along with migrating songbirds and waterfowl, are among the highlights of spring.

In summer, the white flower spikes of sweet pepperbush perfume the air, and you’ll find no fewer than a dozen different ferns on the woodland floor. Look for the night heron as you hike the trail. In autumn, the tupelo is one of the first trees to explode in a fireball of foliage color, as migrating birds stop to feed and rest on their journey south. Winter, when the ground is frozen, is a great time to explore Sagg Swamp. Without their leaves, tree trunks and branches are etched against the sky, and it is easy to see overwintering birds.

Sagg Swamp Preserve | Long Island Explore the beauty of nature at our Sagg Swamp Preserve with Long Island Preserve Director Kevin Munroe.