Northeast Coastal Areas Study
Significant Coastal Habitats
Site 25 (CT)
I. SITE NAME: Connecticut River and Tidal Wetlands Complex
II. LOCATION: This wetlands and river complex consists of over 20 individual tidal wetland units and river islands of various sizes occurring along a 40-mile (64 km) stretch of the lower Connecticut River from Old Saybrook to Cromwell. Taken as a whole, this complex represents a gradation of tidal wetlands from a very narrow zone of relatively high salinity marshes at the mouth of the Connecticut River where it enters Long Island Sound, through an intermediate zone of brackish, lower salinity wetlands, to extensive freshwater tidal marshes and floodplain forests beginning at Deep River and extending upriver to Cromwell.
TOWNS: Chester, Cromwell, Deep River, East
Haddam, East Hampton, Essex, Haddam, Lyme, Old Lyme, Old Saybrook
COUNTIES: Middlesex, Hartford
USGS 7.5 MIN QUADS: Old Lyme, Conn 41072-33; Essex, Conn 41072-34; Hamburg, Conn 41072-43; Deep River, Conn 41072-44; Haddam, Conn 41072-45; Middle Haddam, Conn 41072-55; Middletown, Conn 41072-56
USGS 30x60 MIN QUADS: New Haven 41072-A1; Hartford 41072-E1
III. GENERAL BOUNDARY: The following list of significant tidal wetland units occurring along the lower Connecticut River from Old Saybrook to Cromwell, regardless of protected status, is arranged here in order from the closest to the farthest from the mouth of the river, and thus follows a gradient from the saltiest to the freshest. All are subject to the influence of the rise and fall of tidal waters. Those wetlands in special need of protection, in total or in part, are indicated by asterisks (*), and approximate boundary outlines of each of those particular units are delineated on the general area map. Approximate acreages for each wetland unit in the following list, including upland buffers and adjacent tidal flats, are in parentheses. These acreage figures are rough estimates for the total unit and do not necessarily represent either the actual number of strictly wetland acres involved or total acres needing protection or acquisition.
A. Brackish Tidal Wetland Units (Total: 4,325 acres/1,752 ha)
1. Oyster River/Back River Marshes (550 acres/223 ha)
2. Great Island, Upper Island and lower segments of the Black Hall, Duck and Lieutenant Rivers (1,350 acres/547 ha)
3. North and South Coves (650 acres/263 ha)
4. Ragged Rock Creek (400 acres/162 ha)
*5. Ferry Point (110 acres/45 ha)
6. Lord Cove, including Calves, Goose and Nott Islands (650 acres/263 ha)
*7. Great Meadow (425 acres/172 ha)
*8. Hamburg Cove/Eight Mile River (190 acres/77 ha)
B. Freshwater Tidal Wetland Units (Total: 3,546 acres/1,436 ha)
*9. Joshua Creek (25 acres/10 ha)
10. Selden Creek and Cove (1,100 acres/446 ha)
*11. Post and Pratt Coves (130 acres/53 ha)
*12. Eustasia Island (11 acres/4 ha)
*13. Deep River (70 acres/28 ha)
*14. Chester Creek (120 acres/49 ha)
*15. Whalebone Creek and Cove (120 acres/49 ha)
16. Chapman Pond (190 acres/77 ha)
*17. Salmon Cove and River (415 acres/168 ha)
18. Seymour State Park/Higganum Meadows (100 acres/41 ha)
*19. Pecausett Meadows (125 acres/51 ha)
20. Boggy and Round Meadows (400 acres/162 ha)
*21. Dead Man's Swamp (220 acres/89 ha)
*22. Gildersleeve Island and adjacent shoreline (120 acres/49 ha)
*23. Wangunk Meadows (400 acres/162 ha)
IV. OWNERSHIP/PROTECTED STATUS: Of the 23 wetland/island units comprising this complex, at least 14 (61%) are in need of protection and/or management, either wholly or in part. While some are entirely privately-owned, many have some form of protective ownership. Several of these areas contain individual parcels owned and managed by the Connecticut Department of Environmental Protection or by conservation groups such as The Nature Conservancy, Connecticut River Gateway Commission and various Town conservation and land trusts.
V. GENERAL HABITAT DESCRIPTION: The Connecticut River is the only major river in the Northeast without a major urban port or harbor at its mouth. The adjacent uplands over a considerable distance along the lower river have escaped urbanization and exist in a relatively rural and very scenic condition. The tidal wetlands of the lower Connecticut River are largely marshlands dominated by several species of emergent grasses, sedges, rushes, mixed forbs, and cattails. As mentioned previously, these wetlands represent a gradient series from saline to freshwater. In a very narrow zone near the mouth of the river, where surface water salinities are greater than 15 parts per thousand, but less than that of seawater (approximately 32 parts per thousand), the vegetation is primarily salt marsh, dominated by dense, monotypic stands of cordgrass (Spartina alterniflora and S. patens). Tidal amplitude in this area is about 3.5 feet (1.07 m). A little further upstream, brackish tidal marshes are well-developed in the zone where surface water salinities are between 0.5 and 15 parts per thousand. Here the vegetation becomes increasingly more diverse than that of the salt marshes, and contains extensive pure and mixed stands of cattail (Typha angustifolia), bulrush (Scirpus pungens), freshwater cordgrass (Spartina pectinata) and wild rice (Zizania aquatica). North of Deep River, where the tidal surface waters of the river are completely fresh (less than 0.5 parts per thousand salinity), both species and community diversities of the marshes increase dramatically. Perennial sedges and grasses are conspicuous, especially wild rice, bulrushes (Scirpus pungens and S. validus) and reed grass (Calamagrostis canadensis), along with many species of forbs. Further upstream, for example at Dead Man's Swamp and Wangunk Meadows, floodplain forests become more common and better developed, characterized by such trees as cottonwood (Populus deltoides) and red and silver maples (Acer rubrum and A. saccharinum).
VI. SIGNIFICANCE/UNIQUENESS OF AREA: From a regional standpoint, there are no areas in the Northeast that support such extensive or high quality fresh and brackish tidal wetland systems as those in the Connecticut River estuary. In addition to their restricted occurrence, these marshes are significant for the following reasons: 1) they are exceedingly more diverse in species and structure than salt marshes, which contributes to their greater use by fish and wildlife of all types; 2) they are critical habitats for a variety of rare plants and animals (e.g. bald eagle (Haliaeetus leucocephalus), osprey (Pandion haliaetus), puritan tiger beetle (Cincindela puritana), black rail (Laterallus jamaicensis), least bittern (Laterallus jamaicensis), northern harrier (Circus cyaneus), American bittern (Botaurus lentiginosus), golden club (Orontium aquaticum) and Parker's pipewort (Eriocaulon parkeri)); 3) no two marshes are identical; 4) wild rice marshes are an outstanding wetland habitat type which function as significant resting and feeding areas for migratory waterfowl, shorebirds, and rails; and 5) productivity can equal or exceed that of salt marshes in the region. These areas are especially important wintering habitats for American black duck (Anas rubripes). Aside from the marshes themselves, the waters, tidal flats and river bed of the Connecticut River are important finfish and shellfish areas, especially for anadromous fish such as Atlantic and shortnose sturgeon (Acipenser oxyrhynchus and A. brevirostrum), Atlantic salmon (Salmo salar), American shad (Alosa sapidissima) and blueback herring (Alosa aestivalis), and for American oyster (Crassostrea virginica) and soft-shelled clam (Mya arenaria). Many of these finfish species migrate north into Massachusetts and northern New England through an extensive biological corridor linking marine waters of the Atlantic Ocean and Long Island Sound with freshwater spawning areas far inland.
VII. THREATS: Although wetlands in Connecticut are regulated by State and Federal laws, such areas and the species which depend upon them continue to be adversely impacted by various types of human disturbances and activities (e.g. burning, mowing, mosquito ditching) and habitat alteration of upland borders and tributaries. In addition, illegal fills and activities occur over the area. Overharvesting of fish, shellfish and waterfowl are major concerns, as is the threat of oil spills and toxic contamination in the river. Dredging, dredge spoil disposal, land fills, marina development, stormwater discharges, non-point source pollution and increased sediment loads pose significant problems for living resources in and along the river. There have also been various proposals to impound certain marshes, to locate a sewage treatment plant at the mouth of the river and to divert water from the river to supply water to Boston. Invasive species such as common reed (Phragmites australis) and purple loosestrife (Lythrum salicaria) threaten the typical marsh vegetation of several wetlands in the complex.
VIII. CONSERVATION CONSIDERATIONS: A substantial portion of this regionally, and probably nationally, significant tidal marsh complex remains unprotected and/or is not being effectively managed so as to maintain its high species and habitat diversity and to optimize fish and wildlife productivity. The current complicated ownership pattern necessitates establishment of cooperative management and conservation agreements among all parties in order to protect this valuable ecosystem in its entirety rather than by any piecemeal approach. Such an arrangement could include zoning ordinances and other restrictions to maintain or enhance existing land uses. There are also a number of potential opportunities for acquisition of private lands, to add to existing State Wildlife Management Areas and Town Land Trusts, or to establish as National Wildlife Refuges or National Estuarine Research Reserves, which will need to be explored further and studied in greater detail to identify specific tracts to be protected or potentially acquired. Congress is currently considering legislation to create a National Fish and Wildlife Refuge on the Connecticut River. This legislation calls for further examination of key sites throughout the Connecticut River watershed from its headwater sources near the Canadian border to the mouth of the river at Long Island Sound. The tidal wetlands section of the Connecticut River should be considered for listing as a Wetlands Complex of International Importance under the Ramsar Wetlands Convention and is currently under consideration by The Nature Conservancy for its Bioreserve Program. Such designations could form the bases for increased cooperative protection efforts.
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