New York Natural Heritage Program
Maritime Freshwater Interdunal Swales
Maritime freshwater interdunal swale at Napeague State Park Stephen M. Young
System: Palustrine
SubSystem: Open Mineral Soil Wetlands

State Protection: Not Listed
Federal Protection: Not Listed

State Rarity Rank: S2
A State Rarity Rank of S2 means: Typically 6 to 20 occurrences, few remaining individuals, acres, or miles of stream, or factors demonstrably make it very vulnerable in New York State.

Global Rarity Rank: G3G4
A Global Rarity Rank of G3G4 means: Vulnerable globally, or Apparently Secure -- At moderate risk of extinction, with relatively few populations or locations in the world, few individuals, and/or restricted range; or uncommon but not rare globally; may be rare in some parts of its range; possibly some cause for long-term concern due to declines or other factors. More information is needed to assign a single conservation status.

Did you know?
The large cranberry (Vaccinium marcrocarpon) found in maritime freshwater interdunal swales is more commonly associated with bogs in New York. It is the same cranberry that is commerically produced for fruit and juice and is used in medical research. The plant is considered a shrub but creeps along the ground, seeming more like a small vine, and has small evergreen leaves. Commercial cranberry beds and maritime interdunal swales are both flooded seasonally, though swales are flooded more irregularly and unpredictably.

State Ranking Justification [-]
There are approximately 20 extant occurrences statewide. The several documented occurrences are small and geographically restricted, but they have good viability and are protected on public or private conservation land. The community is restricted to the Coastal Lowlands ecozone in Suffolk County. The community's trend is declining due to threats related to invasive species, such as common reed (Phragmites australis); groundwater contamination; off-road vehicle abuse; and management practices that alter natural hydrologic processes, such as breach contingency plans. The surrounding landscape is vulnerable to exotic flora invasion and urban development.

Short-term Trends [-]

Long-term Trends [-]