Wildlife & Habitat
Besides Phragmites, other dominant plants in the emergent freshwater wetlands are broad-leaved cattail (Typha latifolia), and a variety of sedges and rushes (Juncus spp., Eleocharis spp., Scirpus spp.). A portion of a red maple swamp lies on the western edge of the refuge. Several scrub-shrub wetlands are scattered throughout the area, dominated by buttonbush (Cephalanthus occidentalis), swamp rose (Rosa palustris), and swamp loosestrife (Decodon verticillatus).
A unique rare plant site, containing six species the State considers rare or endangered, lies within the grassland habitat on Ninigret Refuge. The rare species include colicroot (Aletris farinosa), slimspike three-awn (Aristida longespica), yellow-fringed orchids (Platanthera ciliaris), tall- and few-flowered nutrushes (Scleria triglomerata, S. paucifolia), and Indiangrass (Sorgastrum nutans).
Approximately 16 percent of the refuge is upland shrub habitat. Shrubland communities vary in height and composition but are usually dominated by northern arrowwood (Viburnum dentatum), sumacs (Rhus spp.), bayberry (Myrica pensylvanica), highbush blueberry (Vaccinium corymbosum), or shadbush (Amelanchier canadensis). Non-native plants such as Asian bittersweet dominate about 15 acres and have affected upland areas by crowding out native trees and shrubs.
The forest cover type has increased the most in the past 15 years, and now totals 413 acres, or 59 percent of the refuge. On forested refuge lands below Route 1, red maple and black cherry (Prunus serotina) dominate upland forest cover, followed by eastern red cedar (Juniperus virginiana), quaking aspen (Populus tremuloides), and gray birch (Betula populifolia). Red maple dominates the forested wetlands. Some remnant pitch pine (Pinus rigida) is also found on the refuge. The two refuge tracts north of Route 1, totaling 292 acres, are upland deciduous forest dominated by various oaks, hickory, and red maple, followed by eastern red cedar and white pine.
Intensive surveys have shown invasive plants to be wide-spread on Ninigret Refuge at varying densities. Asian bittersweet and Phragmites are two of the most common invasive plants on the refuge, and dominate cover on 15 and 32 acres, respectively. Autumn olive is also fairly common on the refuge, and was actually planted during the 1980’s along the runways as wildlife food. This species occupies about 4 acres and continues its aggressive spread. Several species of honeysuckle are also found throughout refuge lands, comprising about 14 acres total. Honeysuckles exist at lower densities than the other invasive species, and are found in more shaded areas.
Threatened and Endangered SpeciesFederal-listed: Piping plover, a threatened species, have nested either on the barrier beach portion of the refuge or on the adjacent Ninigret Conservation Area every year since 1993.
BirdsThe wide variety of habitats have contributed to the great diversity of birds found on Ninigret Refuge. Approximately 70 species are known to nest on the refuge. Recent mist-netting on refuge lands has shown that gray catbirds (Dumetella carolinensis), common yellowthroats (Geothlypis trichas), and red- winged blackbirds (Agelaius phoeniceus) are the most abundant nesting birds in the shrub community. Other birds using early successional shrub and grassland vegetation for nesting include white-eyed vireo, black-billed cuckoo, willow flycatcher, northern bobwhite, prairie warbler, and American woodcock. Recently, bobolink, eastern meadowlark, eastern bluebirds, and wild turkey have been found nesting on the refuge. Birds using the wetlands include green herons, wood ducks, Virginia rails, swamp sparrows, and marsh wrens. Winter birds present on the refuge include northern harrier, shorteared owl, eastern bluebird, and a variety of sparrows. Waterfowl include black duck, mallard, American wigeon, and green-winged teal. Ninigret Pond is an important wintering area for bufflehead, common goldeneye, greater scaup, and red-breasted merganser.
MammalsTwenty-two species of mammals have been observed on the refuge. Large mammals include white-tailed deer (Odocoileus virginianus), coyote (Canus latrans), red squirrel Tamiasciurus hudsonicus), red fox (Vulpes fulva), raccoon (Procyon lotor), striped skunk (Mephites mephites), and eastern cottontail (Sylvilagus floridanus). Mink (Mustella vison) and river otter (Lutra canadensis) have been observed on or adjacent to the refuge. Small mammals include eastern meadow vole (Microtus pennsylvanicus), white-footed mouse (Peromyscus leucopus) and woodland jumping mice (Napaeozapus insignis).
InvertebratesIn July 2008, refuge staff and volunteers participated in the annual butterfly count organized by the National Audubon Society. We surveyed the Ninigret salt pond and headquarters units and volunteers surveyed Trustom Pond fields and along Moonstone Beach Rd and beach. Notable finds include the variegated fritillary at Ninigret and Baltimore checkerspots at Sachuest. The list of species found at Ninigret included Black Swallowtail, Eastern Tiger Swallowtail, Pieridae, Cabbage White, Clouded Sulphur, American Copper, Edwards Hairstreak, Eastern Tailed-Blue, Variegated Fritillary, American Lady, Little Wood Satyr, Common Wood Nymph, Monarch, Little Glassywing, and Dun Skipper.
During August of 2008, refuge staff participated in a Regional effort to inventory bee species on National Wildlife Refuges in Region 5. Species on Ninigret included: Agapostemon texanus, Agapostemon virescens, Andrena brevipalpis, Augochlorella aurata, Ceratina calcarata, Ceratina calcarata/dupla, Ceratina dupla, Halictus ligatus, Hylaeus affinis/modestus, Lasioglossum ellisiae, Lasioglossum imitatum, Lasioglossum pectorale, Lasioglossum pilosum, Lasioglossum rohweri, Melissodes bimaculata and Sphecodes atlantis.
Deer tick surveys indicate that Ninigret Refuge is a hotspot for ticks carrying Lyme disease, erlichiosis, and babesiosis.
Amphibians and ReptilesThe red maple swamp and the small pools scattered throughout the refuge provide the best habitats for amphibians. Amphibians generally do not occur within tidal waters because salt water dries their skin. Gray tree frogs (Hyla versicolor), spring peepers (Pseudacris crucifer) and green frogs (Rana clamitans) are the most abundant frog species. Red-backed salamanders (Plethodon cinereus) were the only members of that group found on the refuge, but other salamander species probably occur in the area. Snapping, painted, and spotted turtles (C. guttata) are abundant in most of the ponds on the refuge. They are also known to occur in brackish water and may venture out into estuaries. Recently, eastern box turtles (Terrepene carolina) have been found in the uplands. Six species of snakes have also been observed on the refuge: eastern garter snake, ribbon snake (T. sauritus), northern water snake (Natrix sipedon), black racer (Coluber constrictor), eastern milk snake (Lampropeltis triangulum), and northern brown snake (Storeria dekayi).
FishSince Ninigret Pond is not technically part of the refuge, we do not manage the fisheries resource. According to the Coastal Salt Pond Special Area Management Plan, more than 100 species of finfish and shellfish utilize coastal salt ponds at some stage of their life cycle.