Long Beach Island — One hundred fourteen pairs of piping plovers nested in New Jersey in 2019, a 19 percent increase compared to 2018, when the numbers came in at just 96 pairs – the third lowest since federal listing in 1986. The most significant shift, as stated in a report from state biologists, occurred at the Holgate Unit of the Edwin B. Forsythe National Wildlife Refuge, where pair number increased 61 percent as compared to 2018 – 29 pairs in 2019, versus 18 in 2018 – and was the highest recorded pair number at Holgate since federal listing.
In addition, several historic nesting sites in New Jersey were revived, including in Loveladies, which was last active in 1996.
Ocean County municipal and state properties – Island Beach State Park, Barnegat Light and Loveladies – had the highest productivity statewide this season, with 1.63 fledglings per pair.
The Holgate, Little Beach and North Brigantine Natural Area region fell slightly in productivity this season, but had a significant 27 percent increase in pair numbers – with 42 pairs in 2019 versus 33 pairs in 2018 – attributed almost exclusively to increases at Holgate.
Piping plovers, small sand-and-white-colored shorebirds with a black neck band and orange legs, breed on barrier islands and beaches in New Jersey, arriving in late March and April. The species, the population of which declined to only 108 pairs in 2013, is listed as endangered under the state’s Endangered and Nongame Species Conservation Act.
Slight gains and losses in plover numbers were made throughout the state this year, notes the report, prepared by Emily Heiser of the Conserve Wildlife Foundation of N.J. and the N.J. Division of Fish and Wildlife’s Endangered and Nongame Species Program, and Christina Davis, of the NJDFW’s Endangered and Nongame Species Program.
Overall, the 2019 population of piping plovers “is slightly below the long-term average (117 pairs) and well below the peak of 144 pairs in 2003,” Heiser and Davis wrote. “State-wide productivity (1.24 fledglings/pair) remained above the long-term average (1.03 fledglings/pair) for the sixth consecutive season but falls short of the federal recovery goal (1.50 fledglings/pair) and below last season’s record high productivity (1.51 fledglings/pair).”
Researchers also recorded an unusually high number of unpaired adults this season – 10 – compared to just three the previous year.
The report also details nest success, and points out depredation remains the leading cause of nest failure for the seventh consecutive year. Of the depredated nests, more than half (17, or 58 percent) were lost to mammals, and the majority of those (13, or 76 percent) were lost to red foxes. The remainder of mammalian depredated nests were lost to opossums, American minks and raccoons.
Crows, gulls, ghost crabs and unknown predator species also contributed to some nest loss, as did flooding and nest abandonment.
As Heiser and Davis wrote, the Forsythe Refuge’s Holgate and Little Beach Units and Gateway National Recreation Area’s Sandy Hook Unit maintain 71 percent of the statewide population. “The importance of these federal lands in New Jersey is paramount,” the biologists noted. “They provide the state’s premier nesting and foraging habitats and recreational use can be better managed than elsewhere in New Jersey.”
“Sustained productivity over the last six years is partly attributed to species managers working together and thinking outside the box in the protection of this species,” they added. “Many uncertainties remain in the recovery of piping plovers in New Jersey, including whether the increase in pair number will be sustainable over time. While it is encouraging to see a small distribution shift to a few sites, species managers remain cautious as the impact of many other factors, such as sea level rise, habitat loss, human alteration of the coastline and human subsidized predators.
“Addressing these issues in a dynamic coastal system while managing habitat suitability and increasing pair recruitment will continue to challenge species managers. Despite these challenges, NJDFW is confident that a sustainable population may be achieved through a strong foundation of partnerships on which research, management and monitoring needs are met.”
Heiser and Davis also prepared a short summary of nesting in 2019 for the four primary species of beach-nesting birds in the state: the piping plover, which is federally threatened and state endangered; the black skimmer, which is state endangered; the least tern, also state endangered; and the American oystercatcher, a species of special concern.
“The distribution of beach-nesting birds across the state continues to be in flux,” Heiser and Davis noted. “The pattern of piping plovers primarily nesting at federal sites in the central and northern portion of the state continued, but previous year’s fledges have dispersed into other parts of the state and thus increased the number of pairs at non-federal sites.”
Species commonalities includes depredation, which continued to be the major limiting factor for all species, with red foxes, gulls, fish crows, peregrine falcons, great-horned owls, cats and ghost crabs the confirmed or suspected predators. “Efforts to manage depredation were hindered in some locations by public interference as well as the lower suitability of some sites for trapping,” the biologists said.
New Jersey, in conjunction with Conserve Wildlife, the State University of New York’s College of Environmental Science and Forestry, and The Wetlands Institute, continued to expand its banding program this year. Three of the four species – all but least terns – are banded with field-readable color bands, and biologists are collecting data to better understand population dynamics, natal site fidelity and dispersal, and to improve monitoring.
To learn more about the state’s beach-nesting birds, visit njfishandwildlife.com.
— Juliet Kaszas-Hoch