The goal of Audubon New York’s Long Island Bird Conservation Program is to conduct stewardship, monitoring, outreach, and advocacy to reduce threats to, and increase productivity of, approximately 130 pairs of Piping Plovers, 70 pairs of American Oystercatchers, 540 Least Terns, 14,000 Common Terns, and 1,500 Roseate Terns as well as thousands of non-breeding shorebirds. A key component of the coastal work is monitoring and protecting at-risk shorebirds like the American Oystercatcher; with 51 pairs nesting at our Town of Hempstead site alone, this season was a particularly busy and exciting one!
METHODS
The American Oystercatcher is recognized as a species of special concern by conservation entities including the United States Fish and Wildlife Service, Partners in Flight2, and the National Audubon Society. To conserve this species, the National Fish and Wildlife Foundation Business Plan for the American Oystercatcher recognizes the following needs: management of predation; management of disturbance; management and acquisition of habitat; assessment of reproductive success, survival, and population size; and assessment of potential climate change effects. In accordance with the business plan’s recommendations, the National Audubon Society developed an Atlantic Coast flyway-wide project (funded by National Fish and Wildlife Foundation) in 2013 to gather information and better manage this species across its range. In New York there is little information about the reproductive success of American Oystercatchers. Through this project Audubon New York aimed to document American Oystercatcher productivity at Town of Hempstead beaches and Jones Beach State Park, which are key nesting areas on Long Island for this species, as well as Tobay Beach, a Town of Oyster Bay beach which is located just east of the Jones Beach State Park boundary.
From early April until late August 2017, Audubon New York and Town of Hempstead staff surveyed potential nesting areas at the beaches owned or managed by the Town of Hempstead (from the Long Beach Towers to Jones Inlet), Jones Beach State Park, and Tobay Beach two to three times per week. American Oystercatcher nesting areas, which usually coincided with Piping Plover nesting areas, were pre-fenced with symbolic string fencing at the start of the breeding season. At Jones Beach and Town of Hempstead, the land managers installed the fencing and adjusted it as needed throughout the season. At Tobay Beach, Audubon staff worked with NYS DEC to install the symbolic fencing. Most oystercatcher nests, except for a few at Jones Beach which land managers couldn’t fence off, were located within this protective fencing. Staff walked the beach (outside of the fencing when possible) with binoculars and/or a spotting scope looking for oystercatchers. When American Oystercatchers were located, staff noted their location and observed the birds to determine if they were exhibiting nesting behaviors. If oystercatchers appeared to be incubating, the surveyor checked to see if there were eggs at that location. If eggs were present, the number of eggs were recorded and its location was marked in a GPS unit. Nests were labeled by the adult pair number and nest attempt (“a” for the first nest, “b” for a renest, “c” for a third nest attempt, or “d” for a fourth nest attempt).
Nests were checked on all subsequent visits by observing the incubating adult through binoculars and/or spotting scope. If the adult was incubating it was assumed that the nest was still present. If the adult was no longer incubating or guarding the nest, the nest bowl was checked to see if the eggs were gone and cause of loss (if it could be determined) was recorded. Nests in which eggs disappeared with no sign of flooding or human disturbance were classified as “depredated.” Cause of depredation was determined by tracks or other signs of predators in the vicinity of the nest. Nests lost to flooding, human disturbance, inviable eggs, or abandonment were also recorded. Nests were tracked until they failed or hatched. After nests hatched the chicks were monitored until they fledged or disappeared. Productivity for the sites was determined by dividing the total number of chicks fledged throughout the season by the total number of nesting pairs observed. Pairs were considered successful if they fledged at least one chick.
RESULTS
We located 68 nesting pairs of American Oystercatchers. 51 pairs nested at Town of Hempstead Beaches, 14 pairs nested at Jones Beach State Park, and three pairs nested at Tobay Beach Town Park. At the Town of Hempstead, 51 nesting pairs were located throughout the breeding season. The pairs produced 82 nests. Thirty-nine nests (47.6%) had at least one egg hatch, resulting in 100 chicks. Of the 39 pairs with broods, 28 (79.8%) successfully fledged at least one chick for a total of 48 fledglings at the site resulting in an average productivity of 0.9 fledglings/pair.
The Town of Hempstead beaches and Jones Beach State Park support some of the highest numbers of nesting American Oystercatchers on Long Island, with Town of Hempstead having the greatest number of nesting pairs in the state. Jones Beach supports fewer pairs, but is still a significant breeding site and is a very important stopover site for migrating birds. Within Jones Beach, the West End supported the greatest number of breeding pairs with fewer being found at the eastern portions of the site. The average productivity at Town of Hempstead beaches was above the goal in 2017.
The members of Audubon New York's Coasts Program are: Amanda Pachomski, Long Island Bird Conservation Manager; Jillian Liner, Director of Bird Conservation; and Lindsey DeLuna, Rachel Carson Field Technician.
