Each spring, piping plovers and least terns return to nest and raise their young on Maine’s coastal beaches. They share the beach with other wildlife and with people—both of which affect their ability to survive.
Unfortunately, their survival is not guaranteed.
Both are listed as Endangered Species in Maine, which means they are in imminent danger of disappearing. These birds are an important part of the natural beauty and heritage of Maine’s coast.
By conserving them, we are also conserving our environment, which relies on a delicately balanced interplay of all its inhabitants.
Maine Audubon, the Maine Department of Inland Fisheries and Wildlife, and the U.S. Fish and Wildlife Service work in partnership with other groups to protect and conserve these rare birds.
This is only possible with the assistance of people like you.
Why Do Piping Plovers and Least Terns Need Protecting?
For over 25 years, a coalition of groups (starting with Maine Audubon and now including the Maine Department of Inland Fisheries and Wildlife, The Nature Conservancy, the U.S. Fish and Wildlife Service, the Maine Bureau of Parks and Lands, and municipalities) has worked with local residents, landowners, and beachgoers to protect these endangered shorebirds and increase their populations.
Historically, Maine had more than 30 miles of suitable nesting beaches that may have supported more than 200 pairs of piping plovers and 1,200 pairs of least terns.
Since World War II, however, construction of seawalls, jetties, piers, homes, parking lots, and other structures along the shoreline has reduced the available habitat for these two species by more than 75 percent.
This increase in development has brought many more people and their pets to nesting beaches, which keeps adult plovers from tending to their eggs and chicks, leaving the nests vulnerable to the elements and predators.
In addition, because the nests are hard to see, beachgoers can inadvertently step on them. Sometimes the birds will try to nest again, but a second nest is even less likely to survive later in the summer amid the increased presence of both people and predators.
Encroaching development has also caused an increase in the numbers of foxes, raccoons, skunks, gulls, and crows, which prey on eggs and chicks.
Least terns will aggressively attempt to chase a predator away, but are not always successful.
When a piping plover perceives that a predator is threatening its nest, the bird will attempt to distract it by moving a few feet away, pretending to have a broken wing, and sounding a distress call.
Even if this ruse works, the adult bird’s absence leaves the eggs or chicks vulnerable to the elements.
Piping plovers and least terns are well adapted to surviving losses in the naturally dynamic system of a coastal beach, but only if the system is intact.
The problem is that Maine’s beach systems, like all others on the Atlantic coast, can be dramatically altered by winter storms or exceptionally high tides that erode nesting areas or wash eggs out to sea.
Historically, birds could easily move to other sites; now those sites are unavailable due to development or other beach alterations.
The remaining habitat’s ability to support nesting plovers and terns is further reduced by intense recreational use and continued development.
Are recovery efforts working?
In Maine, piping plover populations have responded to innovative conservation measures and the support of towns and private landowners.
In 2002, as many as 66 pairs of piping plovers nested on Maine beaches, an almost tenfold increase from the mid 1980s.
Unfortunately, due to increased predation on chicks and adults and habitat erosion by heavy storms, the population fell to 40 pairs of piping plovers in 2006. Conservation efforts are constantly changing in response to these new challenges.
The least tern population has rebounded from under 50 pairs in the early 1980s to over 150 pairs in 2003.
Recently, least terns have also suffered from increased predation from “smart” predators. These are crows and fox that have keyed in on least tern nesting sites and learned how to raid the colonies for eggs.
As a result, least terns have begun to nest on Stratton Island amongst the common and roseate terns that already nest there. This affords the least tern with more protection from predators, but means they have to travel longer distances back to the salt marshes too feed.
The last twenty years of conservation work have brought these two species back from the very brink of extinction in Maine.
Maine Audubon continues to work with its many partners to help piping plovers and least terns produce stable populations. By working to restore balance to the beach environment, we can all help these birds recover.