Brittany Woodthorp walked a sandy beach in May 2016 at Waugoshance Point in Michigan’s Wilderness State Park, like she has for nearly a decade, looking for signs of nesting Piping Plovers. The park, 11 miles west of Mackinaw City, at the northern tip of the Lower Peninsula, was once a stronghold for the Great Lakes population of nesting plovers — holding at least 14 nesting pairs decades ago. The last time a pair nested at the point was in 2006.
Woodthorp, a plover monitor for the Michigan Department of Natural Resources, heard the telltale piping sound.
Then she saw a Piping Plover and then another. A pair!
Every day after that, she trekked two miles to the spot. And when she saw the male do its goose-step courtship display next to the female, she knew. “The male stood up really tall, lifted his legs straight up and down really fast, then approached the female,” she recalls. “The female leaned down and let him hop on her back. Confirmed.”
Three chicks fledged from that pair’s nesting attempt — giving Woodthorp, biologists, and other officials and volunteers another ray of hope that restoration work, monitoring, nest protection, captive rearing of abandoned chicks and eggs, and public education is helping the federally endangered species’ population grow. But more works needs to be done and funds raised if the plover is to continue to be successful.
An encouraging year
Piping Plovers nest in three reproductively isolated populations in the United States and Canada. About 2,000 pairs breed in the northern Great Plains, and approximately 2,000 more nest along the Atlantic coast. The two populations are listed as threatened. By contrast, only 75 nesting pairs — including the one Woodthorp discovered — nest along the Great Lakes. The pairs produced a record 138 young in 2016.
Vince Cavalieri, a biologist and the Great Lakes Piping Plover recovery coordinator with the U.S. Fish and Wildlife Service, is encouraged. “One of our recovery goals is to reach 150 pairs in the Great Lakes population and to get 50 pairs outside of Michigan,” he says. “For a long time we were hovering at about 10 or 12. In 2016, we jumped up to 24 outside of Michigan — which includes 15 pairs in Ontario, two in Illinois, two in New York, and at least five in Wisconsin.”
Piping Plovers nest on sandy beaches, often near pebbles with sparse vegetation. They winter along the Gulf and southern Atlantic coasts, although much less is known about their winter habits compared with their breeding season activities.
The males return to their breeding grounds in April and May, flying over their territory with deep wing beats while giving a repeated piping sound. The females return a few weeks later, when the males begin digging scrapes in the sand and perform other courtship activities to attract a mate. “They get flat down on their bellies and kick out backward and shape out the scrape with their belly,” Cavalieri says.
After that, the female sits in the nest cup while the male stands over her, spreading his wings wide and tilting up and down in what biologists call the tilt display. “Once you start seeing that, that’s an indication that nesting is about to begin,” he adds.
Four eggs are laid, and four weeks later, the precocial young hatch. Almost immediately, they begin searching for food. In another month, they’re able to fly and migrate south before the cold autumn winds arrive. Both adults care for the young as they grow, and the male often remains with them and migrates later than the female.
In need of habitat
Habitat loss, human disturbance, and predation have led to the bird’s decline. Historically, 30 pairs nested along the Lake Michigan beach shoreline in Illinois alone, within a space of two miles, according to the 1907 book The Birds of the Chicago Area, by Frank Woodruff. By 1904, in another stronghold, the Indiana shoreline, the species was down to two pairs.
In 1981, just 17 nesting pairs of plovers were left in the Great Lakes population, according to Cavalieri.
Loss of quality habitat has been key — not only the loss of beaches, but pressure from recreational activities as well. “Nests were getting stepped on or crowded out, and that was too much disturbance for adults to successfully raise the chicks,” Cavalieri explains. A recovery program began in 1986 after the species was listed as federally endangered. “Then in the early to mid-1990s, we really started to ramp up protection efforts.”
Biologists began closing small portions of beaches where the plovers once nested. “At Dimmick’s Point at Sleeping Bear Dunes National Lakeshore in Michigan, we did a complete beach closure, because that was one of the strongholds of the plover’s historic nesting range,” he says. “It has one of the widest beach locations in the entire Great Lakes — there’s a mile of rolling dunes a long way from any tree line. It’s really a great habitat spot. That entire point is closed to the public.”
Dimmick’s Point is on North Manitou Island, in northern Lake Michigan. Most of the island is managed as wilderness. People can visit, but to protect plovers, the point is closed from May 1 through August 15 each year. Volunteer and paid monitors look for nesting plovers, and when they find them, they put up nest exclosures to deter predators, then keep tabs on the birds, reporting daily to Cavalieri and other biologists.
The exclosures resemble a wire cage topped with netting. Plovers can move in and out freely, but predators such as crows are kept out. Throughout the plover’s nesting range, other predators, including raccoons, foxes, skunks, coyotes, and raptors, may take eggs, chicks, or even adults.
For example, two years ago pairs of American Kestrels and Peregrine Falcons raised families at Illinois Beach State Park north of Chicago, near where a pair of plovers nested after an attempt in 2009 (and a 30-year absence in the state prior to that). One of the falcons likely killed the male plover, says Brad Semel, a biologist for the Illinois Department of Natural Resources. Remarkably, all four chicks survived and were banded, and one was spotted on the plover’s traditional wintering grounds.
In 2016, two pairs nested at the park. A few volunteer monitors tried to keep tabs on them, but there aren’t enough people to guard the areas daily. The young hatched and survived, and U.S. Fish and Wildlife Service officials banded them in hopes of tracking where they winter and if they nest. In fact, all Great Lakes Piping Plovers — adult and young — are banded for tracking purposes.
Many more strategies are needed, including educating people on how rare the plovers are and on their importance to the ecosystem. “They’ve always been here,” Cavalieri says. “You have these share-the-beach campaigns. A lot of our monitors like to show the public the chicks in their scopes. One of the things I talk about is Piping Plovers are an umbrella species for the Great Lakes ecosystem. By protecting the plovers, it’s like an umbrella protection over the entire Great Lakes dune system, which is the largest freshwater dune system in the world.”
The ecosystem provides habitat for plant species such as the federally listed Pitcher’s thistle, as well as migration habitat for the threatened Red Knot.
Habitat restoration has helped plovers return to their historic nesting grounds, including at Wilderness State Park, where up to 12 pairs have nested in the past. “But for the last 10 years, we didn’t find any Piping Plovers there,” Cavalieri says. The culprit: non-native species, including spotted knapweed, which grows in a dense monoculture. Plovers prefer sparse vegetation.
A federal grant has helped restore plover habitat, which includes removing the non-native plants and reseeding with native ones. “The restoration project required a lot of physical labor,” says Woodthorp, who helped with the work. Mother Nature had a hand, too. “Last year was a good year for ice scour, which pushes pebbles and cobblestones in a way that is attractive to nesting plovers,” she explains.
In addition, restoration involves enhancing what’s called a cobble pan, a flat zone of large gravel that naturally occurs on beaches — and that attracts Piping Plovers to nest.
“I’m hoping next season we have more than one pair,” says Woodthorp. “We did have a couple lone birds that were hanging out on the point mostly around the nesting pair. It’s a big area that could house two or three nesting pairs.”
Other efforts include retrieving eggs or chicks from areas where adults have abandoned the nest and hatching them via an incubator at a facility in Michigan. When the chicks are ready to fly, they’re released into the wild with other Piping Plovers. In 2015, seven chicks rescued as eggs were raised and released. In 2016, six chicks were fledged from the captive facility. In 2014, “due to a lot of abandonments,” Cavalieri says, “we fledged 24 chicks from the captive facility.”
In April 2009, three abandoned chicks were found along the Lake Michigan shoreline in Illinois — the first nesting attempt observed in the state since 1979. Adults likely abandoned the nest due to predation or human disturbance. The eggs were incubated at Lincoln Park Zoo, then the chicks were transported to Michigan, where they were raised and later released at Sleeping Bear Dunes National Lakeshore. One of the chicks later bred at Port Inland in Michigan’s Upper Peninsula.
The majority of the Piping Plover population winters along the Atlantic and Gulf coasts from North Carolina to Texas, as well as into the Caribbean. Cumberland Island National Seashore, on the southeastern Georgia coast, is a major wintering area for Great Lakes plovers. “Some of the birds migrate over 1,000 miles from the Upper Peninsula to the Bahamas, and they need stopover habitat along the way,” says Cavalieri. “To increase the overall survival of these birds, we also need to increase efforts on their wintering grounds.”
Melissa Bimbi, a biologist with the U.S. Fish and Wildlife Service, has been working in the plovers’ wintering habitats for about a decade. She monitors the Carolinas, Georgia, and the Caribbean, while co-workers do the same in Florida and the Gulf States. “When I started working on plovers in 2005, we didn’t know much about them on the nonbreeding grounds,” she explains. “We have come so far. We’ve definitely got our work cut out for us. The most important thing is to collect the data that show where there are negative impacts to the birds.”
Most Great Lakes plovers winter in Georgia and South Carolina. “Georgia’s coastline is a lot less developed than South Carolina’s shoreline,” Bimbi notes. “They have a lot more islands that are undeveloped and only accessible by boat. There’s a lot of recreation pressure where our Great Lakes plovers winter in South Carolina. They go to Hilton Head, a very popular vacation and recreation site. What we’re finding is that the sites we’re monitoring, whether it’s in Georgia or South Carolina, if those habitats are developed and used extensively for recreation, the plovers have a lower survival rate.”
Another issue is renourishment projects, which involve bringing in sand to give homeowners more beach to protect their oceanfront property. “When they put sand on the beach, it depresses invertebrate populations, which is what plovers eat,” Bimbi says. “It can take a couple months to two years for the invertebrates to recolonize.”
If the sand on the beach is a not good match for what was originally present, it makes it hard for the animals to recolonize at all. “What we’re finding in a lot of these projects,” she adds, “is if they have good quality sand, the better it is for the beach, for tourism, for sea turtles, for the invertebrates.” And for Piping Plovers.
The birds require good roosting and feeding habitat in winter. They like to roost in areas with a lot of wrack — spartina grass that washes up on shore and acts as a sand binder. The wrack also serves as wind breaks for the birds and gives them a place to hide and remain camouflaged.
“The reality is, a lot of this stuff is political,” Bimbi says. “In North Carolina, for example, it used to be illegal to build terminal groins (man-made sea walls). They are not good for dynamic barrier islands or Piping Plovers, but a bill recently was passed that allows for four terminal groins to be built in the state.”
Bimbi has been banding plovers at Hilton Head and working to teach people that the beach is an ecosystem that provides a home for many living things. “When they begin to realize that, they become really fascinated,” she notes.
Piping Plovers still face many challenges: ever-increasing recreation pressure, continuing development of beaches on both the breeding and wintering grounds, and, thanks to climate change, rising sea levels. “Still, Piping Plovers have many fans and folks that are looking out for them throughout their range,” Cavalieri explains. “If we can continue to protect the birds on both their breeding and wintering grounds, there is no reason to think we can’t eventually reach recovery.”
“The future for Piping Plovers and other beach-dependent species of conservation concern would be a lot brighter if people embraced the idea of sharing the beach with plants and animals that live there,” Bimbi adds. “We can choose to be good beach stewards by respecting the needs of the living things that use the same sites we do.”