Managing a Rare Island Habitat

Dr. Sarah Treanor Bois
Director of Research & Education at the Linda Loring Nature Foundation

Grasslands | Nantucket, MA

Sandplain grasslands of the northeastern United States are important hotspots for native plant and animal biodiversity.

Nantucket has some of the largest expanses of intact sandplain grassland and heathland habitat. With much of this landscape lost to development up and down the Atlantic coast, almost 90% of the world’s sandplain grassland occurs on Nantucket, Martha’s Vineyard, and a slice of Long Island. We know these habitats for their Black Huckleberry, sweet Low- and Highbush Blueberries, fragrant Northern Bayberry, and Little Blue-stem grasses rolling in the winds. The grasses, low shrubs, and multitude of wildflowers define this habitat. These plant communities are host to a number of regionally and globally rare species as well including the Eastern Silvery Aster, Nantucket Shadbush, and the spectacular New England Blazing Star, among others.

While plants are the cornerstone for ecosystems everywhere, sandplain grasslands and coastal heathlands support a diversity of life found in few other locations. Northern Harrier Hawks and Short-Eared Owls hunt and nest in the grassland/shrub mix. Grasshopper Sparrows eat, sleep, and nest on the ground—impossible to do off-island where skunks, raccoons, and other nest predators are about. Grasslands and heathlands are also host to a multitude of insect fauna, including at least 19 rare species. This includes important pollinators, dragonflies, butterflies, and moths.

Sandplain grasslands are early successional habitats, which means they require maintenance and active management to stay grasslands. In some areas of Nantucket, high winds, salt spray, and deer browse are enough “management” to maintain the grassland mix. However, many properties require more disturbance to prevent woody shrubs from becoming the dominant vegetation. That is why you may see large mowers and evidence of prescribed fire in your favorite conservation areas.

Many of the island’s conservation groups have been working for decades to maintain and sometimes reclaim sandplain grasslands. Recently, however, continued regrowth of woody vegetation, increasing threats due to climate change, and limitations on management methods have inspired local conservation professionals to look beyond Nantucket to see what others are doing in similar habitats.

Grasslands group | Nantucket, MA

The Sandplain Grassland Network, a new regional partnership among scientists and land managers, was formed in 2016 to improve management of the globally rare sandplain grassland habitat. The group has been working over the past two years to coalesce published papers, unpublished reports, and conduct interviews with experts. The culmination of this collaborative work is a report, released this month, which details the status of the northeastern sandplain grasslands.

The report calls for more effective management that will require increased use of mowing and prescribed fire. The report also urges greater use of these techniques during the growing season, when their influences in re-ducing shrubs and trees will be greatest. The regrowth of woody vegetation threatens protected sandplain grasslands habitat across the northestern U.S.

The Network released the online report that describes sandplain grassland management successes, lessons learned from past efforts, and recommendations for better managing grasslands in the future. The report contains information from scientific reports and from interviews with more than 30 researchers and managers who have decades of hands-on experiences managing sandplain grasslands from Long Island to Maine. The report also describes new challenges that will arise from climate change, rising sea levels, higher deer populations, and more intensive human use of surrounding coastal lands.

Find Nantucket Hotels at Nantucket.netThis report will be published on the new Sandplain Grassland Network website (whrc.org/sgp), hosted by the Woods Hole Research Center (WHRC).

WHRC Senior Scientist Christopher Neill and The Nature Conservancy’s Karen Lombard led the development of the Network, report, and website in partnership with a Coordinating Committee that includes Sarah Bois of the Linda Loring Nature Foundation, Karen Beattie and Jen Karberg of the Nantucket Conservation Foundation, members from the Central Pine Barrens Joint Planning and Policy Commission, the Massachusetts Natural Heritage & Endangered Species Program, and The Trustees of Reservations.

purple flower | Nantucket, MABecause many sandplain grasslands have already been lost to forest regrowth and residential development, the report urges consideration of creating new habitat on former agricultural lands and expanding high quality existing grasslands onto adjacent woodlands. While this is true for many of the grasslands off-island, on Nantucket, our goals for sandplain grassland management fall mainly into the category of maintenance and expansion rather than creation.

Nantucket was ahead of its time in creating so much open space early on. In so doing, it created some of the best and biggest examples of sandplain grassland and coastal heathland on Earth. We are lucky to be on the side of preservation and maintenance rather than restoration and reclamation seen in other areas.

Interested in seeing more? Visit a sandplain grassland and heathland property and see it for yourself. The island’s south coast is the place to be for these habitats, with many Nantucket Conservation Foundation and Nantucket Land Bank properties open to the public. The Linda Loring Nature Foundation also offers weekly plant and