Boating & Water Access: A Barrier Island Bordered by Back-Bay Marsh
Stone Harbor is a borough in Cape May County, New Jersey, occupying the southern end of Seven Mile Island (also called Seven Mile Beach) - the same barrier island it shares with Avalon to the north. The Atlantic Ocean runs along the island's front side, and behind the island lies a network of back-bay channels and salt marsh that separates the island from the New Jersey mainland. That marsh reaches a particularly notable stretch just south of Stone Harbor at Nummy Island, whose tidal flats and salt-marsh feeding grounds sit near the Stone Harbor Bird Sanctuary - New Jersey's first National Natural Landmark - and draw wading birds that depend on that shallow, undeveloped bay water. This page does not name a specific marina, boat ramp, or dock-rental operation in or around Stone Harbor, and it does not quote slip fees or launch costs - none of that was confirmed in this site's research pass. What follows is grounded in Stone Harbor's documented geography, along with the state and county agencies that can answer the specifics an actual boater needs.
Seven Mile Island: Ocean on One Side, Bay and Marsh on the Other
Seven Mile Island is a barrier island - a narrow strip of land facing the open Atlantic on one side and separated from the New Jersey mainland by bay and marsh water on the other. Stone Harbor occupies the island's southern half, with Avalon to the north; both towns trace back to the same 1887 purchase of the island by the Seven Mile Beach Company. That shape defines boating access here the same way it does on every barrier-island community along this coast: ocean-side water, with its swell, current, and open exposure, behaves differently from the calmer, shallower back-bay channels behind the island, and neither should be assumed to behave the way it did last season.
This site has not confirmed the specific back-bay marina locations, boat ramps, or dock-rental facilities that serve Stone Harbor as distinct from neighboring Avalon on the same island. Rather than guess at which waterway serves which town, this page treats that as a question for local and state sources, not something to flatten into a single generic description of "Seven Mile Island."
Nummy Island and the Marsh Behind the Bird Sanctuary
Just south of Stone Harbor, Nummy Island sits within the same back-bay system, its tidal flats and salt marsh forming part of the feeding grounds tied to the Stone Harbor Bird Sanctuary - a 21.5-acre protected area established by local ordinance in 1947 and designated New Jersey's first National Natural Landmark in October 1965. That sanctuary and the marsh around it are a real, working ecosystem, not scenery: shallow bay water, marsh grass, and tidal flats like these support nesting and feeding waterbirds, and they are exactly the kind of water where depth, channel markers, and no-wake or protected-area rules can differ meaningfully from a few hundred yards away. A boater unfamiliar with this stretch should treat it as distinct water requiring its own current information, not an extension of a channel or ramp used elsewhere on the island.
This site has not confirmed specific navigational channels, depth markers, or posted boating restrictions for the waters around Nummy Island and the bird sanctuary's marsh. Current conditions there are a question for NOAA nautical charts, the U.S. Coast Guard, and New Jersey's own wildlife and boating-access agencies - not for a general description like this one.
Cape May County: The Right Level for Local Specifics
Stone Harbor is one of several municipalities on Seven Mile Island and the surrounding Cape May County shoreline, and county-level and municipal sources are where confirmed, current detail on boat ramps, marinas, and docking actually lives. This site has not independently verified marina names, slip counts, ramp locations, or rental pricing for Stone Harbor, and none of that is invented here. Readers planning an actual outing should check with Cape May County and the Borough of Stone Harbor directly, since those are the sources positioned to answer where to actually launch, with current, dated information.
Seasonal and storm-driven change is a real factor on this stretch of coast as well. Barrier-island geography here - including the marsh behind Nummy Island - can shift with storms, tides, and sand-management projects. None of that is a substitute for a current chart or a local harbormaster's word on what a given channel or inlet looks like this season, but it is a reminder that bay channels and marsh flats on this island are moving targets, not fixed features.
Registration and Regulation: Where the State Comes In
Boating in New Jersey waters involves state-level rules that this page does not attempt to summarize in full. Boat registration and titling in New Jersey is handled through the New Jersey Motor Vehicle Commission, and readers should confirm current registration requirements, fees, and safety-equipment rules directly with that agency rather than rely on assumptions carried over from another state.
Fishing and boating access tied to New Jersey's public waterways - including boat-access sites the state itself maintains, and any rules specific to protected marsh and wildlife areas like the waters near the Stone Harbor Bird Sanctuary and Nummy Island - falls under the New Jersey Division of Fish and Wildlife. For anyone weighing where public water access exists near Stone Harbor, that division, alongside Cape May County and the Borough of Stone Harbor, is the accurate source, not a guess made from this page.
What This Page Does Not Claim
This page does not name a specific marina, boat ramp, launch site, or dock-rental facility in or around Stone Harbor, and it does not state slip counts, launch fees, or rental prices. None of that was confirmed in this site's research pass, and rather than borrow a figure from a neighboring Jersey Shore market, this page directs readers to Cape May County, the Borough of Stone Harbor, the New Jersey Division of Fish and Wildlife, and the New Jersey Motor Vehicle Commission for current, verifiable specifics.
It also does not offer legal, tax, insurance, or financial advice - including on riparian rights, dock permitting, flood zone status, or the property-tax treatment of waterfront or near-water parcels. New Jersey's tax structure, including its state sales tax, differs from the no-sales-tax framework used in some other markets this site covers, and this page does not assume otherwise. Anyone making a decision based on these questions should consult a licensed New Jersey attorney, a tax professional, or an insurance agent, and verify directly with the relevant county, municipal, or state agency.
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Get a Free Agent Referral →Independent research. No ads. No sponsored listings. Confirmed: Stone Harbor is a borough in Cape May County, New Jersey, on Seven Mile Island, a barrier island facing the Atlantic Ocean and bordered on its bay side by back-bay marsh, including the tidal flats near Nummy Island tied to the Stone Harbor Bird Sanctuary (established 1947, designated New Jersey's first National Natural Landmark in October 1965). This page does not name any specific marina, boat ramp, launch site, or dock-rental facility, and does not state slip counts, launch fees, or rental prices - none of that was confirmed in this research pass, and none of it is invented here. Verify current boating access, ramps, and marina details with Cape May County and the Borough of Stone Harbor; verify boat registration requirements with the New Jersey Motor Vehicle Commission; and verify public waterway access with the New Jersey Division of Fish and Wildlife. Nothing on this page is legal, tax, or financial advice.