UMaine Part of 4-Year Regional Effort to Conserve Tidal Marshes – B. Olsen

The salt-water tidal marshes along Maine’s coast are part of an intricate network of waterways along the eastern North American coast that are unique globally. Yet the marshes are disappearing due to rising sea water levels and the development of inland and coastal areas.

University of Maine bird biologist Brian Olsen is part of a multi-state study looking at the loss of salt-water marshes from Maine to Virginia and its effect on bird species that rely on that habitat.

The work is critical, Olsen said, because eastern North American tidal marshes are home to 56 percent of the world’s endemic salt marsh species or subspecies.

“This is our rainforest,” Olsen said. “This ecosystem is a North American phenomenon and because of that, it’s a strongly North American responsibility. If we don’t work to conserve it, the planet loses something.”

The project has a budget of $1.1 million, including a 4-year, $760,202 grant from the U.S. Department of the Interior. Researchers in Maine, Connecticut, Delaware and Maryland are the primary partners, with other researchers participating in New Hampshire, Massachusetts, Rhode Island, New York, New Jersey, and Virginia.

Tom Hodgman of the Maine Department of Inland Fisheries and Wildlife is the other primary researcher in Maine.

Although the situation is not as dire in Maine, said Olsen, tidal marshes in Chesapeake Bay states such as Maryland and Virginia have already started to disappear.

“There are places that used to be huge emergent plains that are just open water now, and islands that have disappeared down there,” he said.

The first step of the project involves technicians and volunteers making systematic surveys of thousands of points in marshes in the region, including more than 100 marshes in Maine, to determine the density of birds and the centers of distribution of different species.

After those determinations have been made, researchers will determine how demographic rates vary in the region. Six sites have been chosen in the region with one of a group of graduate students, including UMaine students Kate Ruskin and James Style, located at each site to gather in-depth information to understand how many young are produced on average for each species, and how well the young and adults are surviving. Modeling will be used to interpolate the areas between the six points.

The third step is to compare the data to surveys and studies of species done in the past 10-15 years, a time when there has been marked sea level rise. UMaine graduate student Mo Correll will gather and analyze that data.

“Then we’ll be able to say, here’s a place where the birds are very common and they probably can reproduce pretty well now, but if we look at the trend over the last decade, they’re half of what they were and sinking fast,” Olsen said. “We’ll be able to identify those sorts of places.”

The study’s focus will be on five bird species that are either entirely or primarily dependent on tidal marsh habitat, although not all are found in Maine. The five include the Nelson sparrow, the saltmarsh sparrow, the seaside sparrow, the clapper rail, and the willet. Researchers will also gather data about species such as the American black duck, the red-winged blackbird, the swamp sparrow, herons and egrets, which are not entirely dependent on salt marsh but do use the habitat and would be impacted if it were to disappear.

Part of the third and fourth years of the grant will be aimed at developing recommendations and working at the state level, which the researchers hope will have an impact on decision-making at a more local level. The state of Connecticut is already doing a pilot study in how to pull together different groups to discuss conservation priorities.

“We want the local groups to have a part in the conversation because ultimately that’s where the rubber meets the road, where the conservation and development happens,” Olsen said. “We want local interests to be aware of the responsibility they have in a regional context. That wet spot in your town could play a role in the dynamics of species that span the whole east coast.”