Key Biodiversity Areas

Grand Etang (19923)
St Martin (to France), Caribbean

Site overview


KBA status: confirmed
Year of last assessment: 2009
National site name: Grand Etang
Central coordinates: Latitude: 18.0572, Longitude: -63.1425
System: marine, terrestrial
Elevation (m): 0 to 5
Area of KBA (km2): 0.20984
Protected area coverage (%): 88.37
KBA classification: Global/Regional TBD
Legacy site: Yes

Site details


Site description: Grand Etang is a large saline pond located in the gated Lowlands subdivision of St. Martin. It is approximately 50 hectares in size. Due to its high salinity (>100 parts per thousand), the pond has little vegetation. At the west end, a small pond is separated from the larger pond by a narrow strip of land. Electric wires on poles cross the pond at this point. The surrounding land is low hills of scrub habitat interspersed with roads and homes on large estates. A dirt road runs directly next to the shore along one side. An exclusive resort borders the road.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance because it meets one or more previously established criteria and thresholds for identifying sites of biodiversity importance (including Important Bird and Biodiversity Areas, Alliance for Zero Extinction sites, and Key Biodiversity Areas)
Additional biodiversity: Least Terns nest on a sandy spit located in the smaller pond of Grand Etang. Wilson's Plover nests at the same location and in surrounding areas. In the summer of 2004, nesting success of both species was monitored by EPIC. During that time, a high count of 180 Least Tern nests and 82 breeding pairs was recorded. Ten pairs of Wilson's Plover were recorded. Black-necked Stilt Himantopus mexicanus also breeds at Grand Etang (25 nests).Regionally limited species found at this site include Green-throated Carib Eulampis holosericeus, Antillean Crested Hummingbird Orthorhyncus cristatus, Pearly-eyed Thrasher Margarops fuscatus, and Lesser Antillean Bullfinch Loxigilla noctis. Non-bird biodiversity: Not applicable.

Habitats


Summary of habitats in KBA: Vegetation begins about 5 meters from the waterline and is thorn scrub composed primarily of Acacia. In some areas, the pond borders the yards of upscale homes. The area is residential
Land use: not utilised
IUCN HabitatCoverage %Habitat detail
Wetlands(Inland)100

Threats


Summary of threats to biodiversity at KBA: The primary threat to nesting birds at Grand Etang is flooding. Ten percent of Least Tern nests (n=130) were recorded as submerged after heavy rains raised the water level of the pond. Many others may have been flooded as well, but this could not be confirmed because the chicks may have hatched and moved away from the waterline between checks. Introduced predators are also a major concern for nesting birds. During Least Tern nest monitoring, predation was confirmed at 5% of all nests. Wilson's Plovers experienced a 30% predation rate (n=10) at Grand Etang. The actual percentages are likely much higher. Rats and dogs are the primary culprits. Fresh dog tracks were present at almost every weekly check. A fence should be constructed around the nesting area to keep dogs out. Another possibility is to dredge around the nesting site, creating an island, which would make the area less accessible to predators.Bird are periodically found dead under the powerlines which cross Grand Etang with signs of blunt trauma such as broken necks and wings. The lines may be difficult for the birds to see, especially migratory birds arriving at night. The lines should be rerouted away from the pond or markers should be placed on the lines to make them more obvious.Yard debris from surrounding residences is dumped into the pond and often burned along the shore of Grand Etang. The resort which borders the pond periodically empties its septic system by allowing the sewage and associated debris to flow across the road and into the pond. Funding for the existing sewage treatment plant for this area is not available.An individual with a shotgun was seen once walking around the border of Grand Etang but it is not clear if he was hunting.

Additional information


References: COLLIER, N.C. and A.C. BROWN 2001-2006; DANFORTH, S. T. 1930;HALEWYN, R. VAN, AND R. L. NORTON. 1984; HOOGERWERF, A. 1977;PINCHON, R. 1976;ROJER, A. 1997;VOOUS, K. H. 1954;VOOUS, K. H. 1955a;VOOUS, K. H. 1955b;VOOUS, K. H. 1983. ;VOOUS, K. H. AND H. J. KOELERS. 1967