Wells NERR Research

Overview

The Wells NERR research department studies and monitors change in Gulf of Maine estuaries, coastal habitats, and adjacent coastal watersheds, and produces science-based information needed to protect, sustain, or restore them. In a typical year, the program directs or assists with more than 20 studies involving dozens of scientists, students, and staff from the Reserve, academic and research institutions, resource management agencies, and environmental and conservation groups.

Wells NERR scientists participate in research, monitoring, planning, management, and outreach activities locally, regionally, and nationally. The program supports field research along Maine's southwest coast from the Kennebec River to the Piscataqua River, including nearshore and offshore waters of the Bigelow Bight. Within this region, effort is focused on the coastal compartments from Kittery to Cape Elizabeth, which are characterized by numerous marsh-dominated estuaries and barrier beaches.

Jump to Scientific Publications

Wells NERR Research Themes

Estuarine Water Quality

Water quality is monitored continuously at several stations with automated instruments as part of the System-wide Monitoring Program, as well as bimonthly at 15 to 20 stations through the Watershed Evaluation Team (WET) volunteer monitoring program. These data 1) have allowed us to identify several bacterial "hot spots," 2) are used to identify and open areas safe for shellfishing, and 3) have uncovered a relation between tides and low dissolved oxygen levels. Our water quality work has contributed to the designation of several "Priority Watersheds" in coastal southern Maine by the Maine Department of Environmental Protection. Our partnership with Maine Sea Grant and the University of New Hampshire has identified species-specific sources of bacterial contamination in our coastal watersheds.

Salt Marsh Habitats and Communities

Factors that control the dynamics and vigor of salt marsh plant communities and marsh peat formation determine the ability of a salt marsh to persist in the face of sea level rise. Through a combination of experimental manipulations and long term monitoring, we are producing data to answer questions concerning the sustainability of natural and restoring salt marsh habitats in this region. These studies are looking at nutrient-plant relations, plant community responses to physical and hydrologic disturbance, and the relative contribution of short-term natural events (e.g., storms) and human activities (e.g., dredging, tidal restriction) on patterns of sediment accretion and erosion. The Reserve's marshes and beaches are among the best-studied sites nationally with regard to long-term accretion and erosion (over thousands of years). The barrier beaches that protect these marshes have also been well studied, especially with respect to alterations due to human activity and sea level rise.

Habitat Value for Fish, Shellfish and Birds

The Reserve combines long-term monitoring with periodic surveys and short-term experiments to identify species and measure trends and changes in populations of fish, crustaceans, clams, and birds. We have more than 10 years of data on upland birds, wading birds, and shorebirds for assessing population status. Our wading bird data are used as a gross indicator of salt marsh health. Our periodic larval, juvenile, and adult fish surveys have produced the best available data for fish utilization of salt marsh estuaries and coastal watersheds in the Gulf of Maine. We periodically conduct surveys and field experiments to look at the survival and growth of hatchery seed, juvenile, and adult softshell clams, as well as their favored habitat characteristics and predation by the invasive green crab.

Salt Marsh Degradation and Restoration

Since 1991, the Wells Reserve has been studying the impact of tidal restrictions on salt marsh functions and values, and the response of salt marshes to tidal restoration. Salt marsh ecosystems in the Gulf of Maine sustained themselves in the face of sea-level rise and other natural disturbances for nearly 5,000 years. Since colonial times large areas of salt marsh have been lost through diking, draining, and filling. Today, the remaining marshland is fairly well protected from outright destruction, but during the past 100 years, and especially since the 1950's, salt marshes have been divided into fragments by roads, causeways, culverts, and tide gates. Tidal flow to most of these fragments is severely restricted, leading to chronic habitat degradation and greatly reduced access for fish and other marine species. Under the umbrella of the Global Programme of Action Coalition for the Gulf of Maine, the Reserve evaluates monitoring results from marsh restoration projects throughout the gulf to assess their performance and to identify data gaps and future monitoring needs.

Selected Recent Research Projects

Benthic Habitat Correlates of Juvenile Fish Distribution in the Bigelow Bight and Adjacent Estuaries

Read a news release about this study.

This study allows us to work with, train, and be trained by local fishermen as we study food web linkages between estuarine, nearshore, and offshore groundfish habitats. A Sediment Profile Imager photographs different bottom types and their associated fish prey organisms. Our goal is to identify relationships between juvenile fish, bottom types, and prey types. The results of this study will provide information for development of habitat-based fisheries management. It will also provide a baseline for measuring habitat and fish responses to changes in commercial fishing practices.
Collaborators: University of New Hampshire, University of Maine, Maine Department of Marine Resources

Salt Marshes as an Energy Source for Coastal Food Webs

This experimental study uses stable carbon and nitrogen tracers to measure the contribution of energy derived from salt marsh grasses to estuarine food webs, especially for fish. We are also measuring the influence of stormwater runoff and other hydrologic alterations on the marsh food web and its productivity. This study is our first as part of the Long Term Ecological Research Project (on our links page) for Plum Island Sound, for which the Wells NERR serves as a northern field site.
Collaborators: Woods Hole Marine Biological Laboratory--Ecosystems Center, University of New England, University of Southern Maine

Watershed Shoreland Surveys

The Merriland River, Branch Brook, Little River shoreland survey report is now available. Read the summary. (2002-08-14)

Teams of trained volunteers survey selected stream segments, describing all potential pollution inputs observed within a 250-foot shoreland zone on each river bank. Pollution sources are categorized and ranked in terms of potential disturbance to the watershed.
Collaborators: Multiple partners within each river's community.

Salt Marsh Erosion and Accretion in Response to Natural and Human Disturbance

We are documenting patterns of sediment erosion and accretion within the marsh-dominated Webhannet estuary in response to both natural disturbance from storms and ice and anthropogenic disturbance through harbor dredging.
Collaborators: Boston University, University of Maine, Maine Geological Survey, Maine Sea Grant, University of New Hampshire, Brown University

Mapping Coastal Water Quality

We are testing a new device being developed at the North Carolina NERR in several Maine water bodies. The device transforms a standard water quality data logger, normally deployed at fixed points, into an instrument that can be towed and georeferenced to create contour maps of water quality for entire water bodies. We are using the instrument to measure the influence of natural sources of organic matter (such as salt marsh peat) and human sources of nutrients and organics (such as sewage effluent) on spatial patterns in water quality. This study addresses questions about depressed dissolved oxygen patterns observed in a 1995-1996 statewide coastal survey.
Collaborator: North Carolina NERR

Fish Use of Natural, Degraded, and Restored Coastal Habitats

For 10 years we have surveyed and studied fish fauna of southern Maine estuaries and coastal watersheds. Our current emphases are on the York River and Casco Bay.
Collaborators: York Land Trust, York Rivers Association, University of New England

Ecological Functions of Fringing Salt Marshes Susceptible to Oil Spills in Casco Bay, Maine

Casco Bay is the largest oil port in northern New England, handling over 20-million tons of crude oil and oil products annually. Oil spills could cause extensive damage to the Bay's ecosystem. Because the Casco Bay marshes are predominantly fringing marshes that serve as nursery grounds for finfish and shellfish, more information is needed about their ecological role in the estuaries of New England. To measure these functions, the researchers will map marshes, survey fish and invertebrate populations, assess plant communities, and investigate sediment accretion rates. This information will help guide oil spill management and improve the baseline knowlege for assessing natural resource damage if a spill affects the marshes.
Collaborators: University of New England

Microbial Source Tracking

The Microbial Source Tracking project investigated non-point source pollution in the Webhannet estuary and Little River estuary watersheds in Wells, Sanford, and Kennebunk. This project focused on the Webhannet watershed from December 2001 to September 2002, and the Little River watershed from December 2002 to September 2003. Learn more at the MST web site.
Collaborators: Maine Sea Grant, University of New Hampshire Jackson Estuarine Lab, Cooperative Institute for Coastal and Estuarine Environmental Technology

Visiting Investigators

In addition to the projects described above, the Wells Reserve hosts numerous visiting scientists. Their diverse investigations have encompassed the effects of land use, sea level rise, and climate on estuarine productivity; relationships among soil nutrients, soil salinity, and plant community patterns and interactions; habitat use by upland birds; and the ecology of Lyme disease.

For more information contact:
Dr. Michele Dionne (207) 646-1555 x136
dionne@wellsnerr.org