In 1985, Connecticut replaced the standard practice of maintaining the existing mosquito ditch network throughout its tidal marsh system with that of open marsh water management (OMWM) techniques. Abandonment of the ditch network restores preditching water table conditions and habitats such as pannes. Although OMWM was developed as a mosquito control technique for natural marshes, certain OMWM techniques actually serve an important habitat restoration function in ditched tidal marshes. For example, the construction of shallow ponds quickly recreates a habitat type - open water ponds - that was lost from the marsh landscape as a result of intense ditching. It is uncertain whether natural ponds will ever reestablish on the marsh simply through the abandonment of ditches without any other active management practice. To date, OMWM techniques have been used for only a few small wetland areas on the lower Connecticut. CTDEP and the Service are experimenting with the use of OMWM techniques expressly for waterfowl management purposes in the McKinney National Wildlife Refuge in Westbrook, Connecticut. If positive results culminate from these practices, this program will likely be extended into Connecticut River sites such as the Great and Upper Islands.
Tidal wetland restoration projects have occurred at three sites on the lower river. The first includes tidal flow restoration and herbicide control at the small wetland located between CTDEP's marine headquarters at Old Lyme and the railroad embankment. The second project includes creek and tidal flow restoration at a small wetland at Saybrook Point in Old Saybrook. The third site is a diked marsh in Ragged Rock Creek to the north of the railroad embankment. At this location the existing small culvert was replaced with four large culverts. Each pipe was set at an angle positioning the seaward end of the pipe at approximately -1 meter (-3.0 feet) below mean low water. At this depth, the salt content has been observed at times to exceed 20 ppt. In addition, the internal creek and ditch network were cleaned to facilitate better flushing. This combination of flushing and elevated salt concentration is expected to reduce the extent of common reed in this wetland.
Haddam Meadows contains an 18-acre marsh that is currently managed for the enhancement of northern pike, accomplished through the use of dikes and weirs to regulate water levels. In the spring, rainfall and high river flows allow the marsh to be filled to an optimal depth for spawning. Adult pike are captured in the downstream section and introduced to the upper marsh to spawn. Later in the season, water levels are drawn down and juveniles are captured and transported to other water bodies, mostly along the Connecticut River.
The lower Connecticut River from Salmon River Cove to the mouth is part of CTDEP's annual statewide midwinter waterfowl survey, and the entire river is part of the annual statewide wintering bald eagle survey. CTDEP takes an annual census of the osprey population on the river, annually measures its breeding success, and constructs and maintains osprey nesting platforms. At Griswold Point, CTDEP annually conducts censuses, measures breeding success, and encloses nesting areas for piping plover and least tern. The population of the Puritan tiger beetle, a U.S. threatened species and state endangered species, is counted and monitored annually, and a translocation of individuals to establish a new population is being attempted.
10. SCIENTIFIC RESEARCH AND FACILITIES:
There are a number of research facilities and academic institutions in the vicinity of the project area that are actively engaged in scientific studies and research on the lower Connecticut River and associated tidal wetlands. These include: Connecticut College, Trinity College, University of Connecticut, University of Massachusetts, University of New Haven, University of Southern Connecticut, Wesleyan University, and Yale University, as well as several community colleges. Drs. Suzanne O'Connell and Peter Patton of Wesleyan University and Dr. Ralph Lewis of CTDEP's Long Island Sound Natural Resources Center are jointly conducting studies to use shallow water side-scan sonar technology to map the bottom sediments/cover types in Long Island Sound between Hatchetts and Cornfield Points and in the lower Connecticut River as far north as Salmon Cove. This project will endeavor to enter the shallow coves of the river and will supplement The Nature Conservancy's SAV project (see below). Drs. Scott Warren and Paul Fell from Connecticut College are investigating the ecological role of Phragmites australis in several brackish marshes in the estuary. Drs. Evamaria Koch and Charles Yarish of the University of Connecticut (Stamford) are conducting a coastwide survey of eelgrass and widgeon-grass to determine present-day distribution. This study will provide much-needed data on the distribution of these species at the mouth of the Connecticut River, and will be used to assist in restoration planning efforts. Drs. James O'Donnell and Frank Bohlen of the University of Connecticut (Avery Point) are characterizing and modeling the flow dynamics of the lower river.
The Nature Conservancy, as part of its Connecticut River Tidelands Program, is especially active in conducting various research studies in the project area. One of their major studies is mapping the submerged aquatic vegetation in the project area and studying its patterns of distribution within the river, using both field investigations and aerial photo interpretation. The organization is also funding and overseeing research projects on the Puritan tiger beetle, relationships between Phragmites australis and bird populations in marshes along the lower river, vegetation dynamics of freshwater tidal wetlands, and mapping of invasive species populations within some of the lower Connecticut River marshes.
CTDEP's Wildlife Division is conducting a survey of northern diamondback terrapins in coastal waters, with an emphasis on their status in the Connecticut River estuary. The CTDEP's Fisheries Division, located at the CTDEP Marine Headquarters near the mouth of the river in Old Lyme, routinely conducts estuarine and riverine fisheries surveys in the project area. One such study involves the use of radio-telemetry to monitor the movement of shortnose sturgeon, estimate population abundance, and identify important concentration and use areas. CTDEP's Wildlife Division conducts annual winter waterfowl surveys throughout the state and provides critical data on waterfowl use on the Connecticut River. Both the State of Connecticut and U.S. Fish and Wildlife Service conduct population surveys on federal- and state-listed species in this area.
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