Protected shorebirds

How the American oystercatcher reclaimed its Island home.

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In the spring of 2017, walking along the sea wall to the Lagoon Pond Bridge, I saw two large, exotic-looking birds I’d never seen before, stalking about and foraging at one of the beaches formed by a small breakwater, emitting piercing cries of “queep … hweep.” Sporting long, thick, bright orange beaks, yellow-rimmed round eyes, and striking black and white plumage, the flamboyant pair were American oystercatchers (AMOY for short), Latin name, Haematopus palliatus. 

In subsequent years, they came back to the little Breakwater Beach. AMOYs mate for life, tend to return to the same nest every year, and can live quite long — up to 20 years or more, so it is likely that these are regular seasonal visitors that are having breeding success at this site. I would observe the parents alternately babysitting and foraging at the beach while the mate foraged all along the area between the bridge and Packer’s Wharf. After the chicks fledged, the whole family foraged together. 

In 2021, awareness of a potential threat to this pair of AMOYs motivated me to learn more about the species. The American Oystercatcher Working Group (AMOYWG) describes the AMOY as “one of the few birds to specialize on bivalve mollusks living in saltwater.” The AMOY’s striking trademark orange bill is a powerful multipurpose tool that is used to stab, wedge, hammer, shovel, lever, and cut — whatever it takes to gain access to a mollusk’s abductor muscle, sever it, pry open the shell, and enjoy the meal, or feed its chicks. In the absence of mollusks, AMOYs plunge these swordlike weapons into the sand to find small crustaceans and worms to dine on. 

According to audubon.org, “Nest … is a shallow scrape in sand, sometimes lined with pebbles, shells.” In other words, they are typically quite exposed to predators, and also to being washed out by high tides. Good foraging territory is also a must; even if it is some distance away, it must be defended, along with the nesting site itself. 

The AMOYWG notes, “Virginia was the northern edge of the breeding limit during the first three decades of the 20th century. The breeding limit gradually moved north over the course of the twentieth century. The first Massachusetts nesting occurred on Martha’s Vineyard in 1969 … The recognition, in 2000, that the entire North American population of this species numbered around 10,000 individuals … led to a flurry of research on its biology [and] to document total numbers.” 

What is the explanation for the AMOY’s expanding range? According to Mass Audubon, the AMOY’s appearance “is more a matter of re-establishing itself in territory once occupied than a bona fide range extension. Oystercatchers were apparently common in [the Northeast] during the early 1800s … By the mid-1800s they had disappeared from the entire Northeast, due in part to excessive hunting (for their feathers and eggs). With protection, oystercatchers gradually began to reclaim some of their former range.” In other words, this “new” population of New England AMOYs is once again migrating north to breed and back south to overwinter.

Protective measures used by programs such as Mass Audubon’s Coastal Waterbird Program include symbolic fencing, signage, electric fencing, and exclosures to protect nest activity and improve reproductive success of AMOYs, as well as other species of concern. Sam Kefferstan, CWP manager for the Islands, states, “We are able to quantify our impact, and our efforts are making a difference. As of 1984, the whole state population was 42 pairs.” Now, on the Vineyard alone, 50 pairs are being monitored by the CWP, BiodiversityWorks, and the Trustees of Reservations, at Lobsterville, Harthaven, and State beaches, Sengekontacket Pond, Cape Poge, Norton Point, Long Point, and Beach Road in Vineyard Haven. Kefferstan considers this pair as “something of an outlier in terms of their nest location, right next to a road with traffic thundering by all day. The rocks against the seawall provide better-than-average protection for the incubating eggs and chicks.” 

It turned out that I wasn’t the only oystercatcher watcher on Beach Road. I often saw Vasha Brunelle perched on the seawall with her binoculars trained on the Breakwater Beach. Brunelle first became aware of these birds about 10 years ago — “because they made so much noise and were so colorful, and I wondered what they were.” She could also see a pair on Ferry Island, in the west arm of the Lagoon, from her home on Beach Road. “I contacted Felix Neck to find out more about these birds, and they suggested I could help them as a monitor with Mass Audubon’s Coastal Waterbird Program. They came and gave me lessons in what to look for in the birds’ behavior, how to behave around them, and how to approach people who are getting too close to them.” As Sam Kefferstan of the Mass Audubon Coastal Waterbird program states, “If they notice you, you’re too close.”

As I’ve watched these birds over the years, I feel a profound connection to what they endure and the obstacles they face to raise and successfully fledge their chicks: find a suitable nesting site, incubate their eggs, protect and feed their chicks. They may lose one or two of their chicks. Ferry Island has changed, and apparently is no longer viable as a nesting site. That pair appeared to be looking for a new site this year, but didn’t breed. Perhaps they got pushback from the Breakwater Beach pair, defending their own foraging territory. At Breakwater Beach, the only interruption in that pair’s breeding record was in 2016, very likely disturbed by the bridge construction. One year, the Breakwater pair had four chicks, but only two survived. This year they started with three, but only two survived. But if they succeeded in fledging two chicks annually for nine years, that is an increase of 18 birds from this one pair. 

An AMOY banding program on the Vineyard would help researchers nail down demographics and migratory patterns of both juveniles and breeding adults. Meanwhile, a great deal of data has been amassed via direct observation by wildlife professionals and volunteers such as Vasha Brunelle.

To me it feels like a gift to be able to know and follow a particular pair of these quirky, characterful birds over many years. I have always approached their nest site circumspectly, to observe them without disturbing them. One day after walking by Breakwater Beach, I looked back through my binoculars and saw one of the adults fly off; then I lost sight of it. As I kept looking for it, I suddenly heard a loud queep. The bird was standing on a boulder right next to the seawall, barely six feet away from me. It had flown to where I was standing. It certainly felt like I was getting the message, “Hey! Look over here!” I was able to observe it up close for a few minutes, until it flew back to home base. Hopefully this special pair of American oystercatchers will be returning to their seasonal home at Breakwater Beach to breed and to fledge their chicks for many years to come. 

For more information on the AMOY and on efforts to protect them and other coastal waterbirds: 

American Oystercatcher Working Group, with photo and video galleries: amoywg.org. Mass Audubon, American oystercatcher: bit.ly/audubonguide. Mass Audubon, Coastal Waterbird Program: bit.ly/audubonprogram. Mass Audubon, Breeding Bird Atlas, American oystercatcher: bit.ly/audubonatlas. BiodiversityWorks, Beach-Nesting Bird Protection: bit.ly/biodiversityworks.

 

2 COMMENTS

  1. Is this relevant to the closing of Norton Point and much of Chappy for the piping plovers? There are a lot of very angry Islanders and visitors who are shut out of those beaches. The Trustees enforcement of protective measures is far more aggressive than in past years, when there was a balance and the birds survived quite nicely. I for one won’t fork over the fee for an OSV pass next year, having been fleeced this one for the Plovers.

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