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Edged in white by 12 miles of coastline, Mashomack Preserve on Shelter Island is considered one of the richest habitats in the Northeast. Just 90 miles from New York City, the preserve covers a third of the island with 2,039 acres of interlacing tidal creeks, mature oak woodlands, fields, and freshwater marshes and is often referred to as the "Jewel of the Peconic."
You can also play a role in the Conservancy’s long-term success on Mashomack when you make a safe and secure online gift to support our global conservation work.
Mashomack was purchased by The Nature Conservancy over 25 years ago, in an effort to stop development of this nearly pristine peninsula and to protect one of the most dense populations of breeding ospreys on the east coast. In the years since, Mashomack has continued to be a favorite nesting place for ospreys, in addition to harboring populations of the endangered piping plover and least tern, as well as a number of rare plants.
A Brief History of Mashomack
The history of Shelter Island dates back to the 1600's, when the island was inhabited by the Manhansets, Native Americans who were part of the wide-spread Algonquin culture. Over the next 400 years, through a fascinating tale traversing generations of wealthy families, stock market crashes, development plans, and hunting clubs, Mashomack miraculously escaped certain demise time and time again.
In 1980, The Nature Conservancy stepped in and was able to secure Mashomack and the rest is history.
See how we’re helping families reconnect with nature at Mashomack Preserve.
Take a virtual visit to Mashomack.
Mashomack Preserve is open 9am to 5pm, March through September, and 9am to 4pm October through February. The preserve is closed Tuesdays, except in July and August when it is open 7 days/week. In January, the preserve is open only on the weekends. A suggested donation of $2.00 per adult and $1.00 per child will help us continue our mission to protect Mashomack for generations to come.
Download a trail map for this preserve.
Please note: No pets allowed.
A birder and botanist's paradise alike, there's no doubt that the biological diversity on Mashomack Preserve is stunning. Learn more>>
In accordance with the Department of Justice’s amended regulation implementing Title III of the 1990 Americans with Disabilities Act (ADA) regarding "Other Power‐Driven Mobility Devices,” Mashomack Preserve has completed an assessment of our public areas and trails. While some types of OPDMDs can be accommodated, there are necessary restrictions on their use. Please download and review the policy prior to your visit.
- Take your best route to Shelter Island.
- When disembarking from the Greenport/North Ferry, follow Route 114 south for three miles to the preserve.
- If you come by way of the North Haven/South Ferry, follow Route 114 one mile north to the preserve.
- A large wooden sign on the east side of Route 114 marks the entrance.
- Park just inside the preserve entrance on Route 114 (less than a mile from the South Ferry) and walk in to the visitor center to sign the guest book and pick up trail maps.
For more information, please contact the Mashomack office at (631) 749-1001.