Shorebird Wrap-up 2016: Vehicle-induced Hatchling Mortality Disrupts Productive Shorebird Season

2016-plover-chicks-at-restoration-area-edge

click to enlarge; plover chicks at restoration area edge

Efforts at fencing, monitoring, education, enforcement, and predator management ensured that minimal nest and hatchling losses occurred, and the highest productivity (chicks fledged/pair) observed since 2001 was achieved this Piping Plover season at Division of Conservation and Recreation (DCR) beaches in Bristol County.

Horseneck Beach produced 24 fledges (23 in 2015) and a productivity of 2.4 chicks per pair, for the most productive year ever at the reservation. At Horseneck, Least Terns did well down the stretch and had a heavy presence near public use areas, especially the new restoration area near facilities where nesting density was highest. This new habitat and increased cobble in the east refuge are both factors that caused the terns to shift onto the main beach, and this season as far as the west dunes. Terns were again a spectacle on the main beach and have become an attraction at Horseneck.

West Island produced six fledges after no hatching at all in 2015, including a nest each on town and state property. A plover banded in New England in recent years (details pending) nested on the town property, producing fledges on her second attempt. Winsegansett Heights, the non-DCR site closely linked to West Island, again had a pair which produced a fledge.

Demarest Lloyd State Park produced only seven fledges (nine in 2015) but with less pairs this season (in line with statewide trends of lower abundance at some small sites) this was a slight increase in productivity, and hatch success improved considerably.

2016-least-tern-chicks

click to enlarge; least tern chicks

With restoration funds from the Buzzards Bay Oil Spill, the United States Department of Agriculture (USDA), predator control efforts, while controversial, have surely helped plover productivity in recent years at our sites, including West Island where crow control occurred for the first time.

However, predators are diverse and adaptable. At Horseneck, deer caused an abandonment in a rare event, and with a bustling deer population, deer presence is becoming an issue to watch. Although stellar hatch success occurred at the site, modest initial predation of the tern colony occurred in the east refuge by coyote, and a pup was observed one morning in the dunes. Even with control efforts, crow managed to take a nest each at Demarest Lloyd and West Island early on. Demarest Lloyd has become the trickiest site, with hatchling predation by both coyote and most recently Great Horned Owl, two ongoing concerns. These species are preventing any Least Tern success at all at Demarest Lloyd.

It’s ironic that Horseneck’s most productive season will forever be remembered as the year a plover chick was crushed accidentally by a beach vehicle. A two-day old chick was found on the paved entrance to the beach, usually the most heavily travelled road in the park. Also ironic, is the fact that the chicks emerged from a nest placed in new sand created in a restoration project designed to improve shorebird habitat! Birds now have dune vegetation and much more sand near facilities than prior seasons when minimal cover existed and birds became trapped on pavement near buildings. However, the roadways that plovers must cross to reach the intertidal zone still exist.

2016-tern-chicks-near-shelter-at-horseneck

click to enlarge; tern chicks near shelter at Horseneck

Each season Lloyd Center staff have worked to prevent hatchling mortalities on a beach where “closures” are difficult to attain. Intensive monitoring during peak hours of beach operation, “closures” of roads or crossings when broods territories are nearby, and communications with various vehicle users during our shifts have helped greatly. But it was only a matter of time before a hatchling didn’t reach the other side on such a busy beach.

A positive outcome was improved collaborations with park workers and law enforcement that became necessary after state and federal personnel directed steps to be taken. Many hours were spent directing and escorting vehicle users of various types through hatchling habitat. And as unfortunate as the loss of the plover was, these communications brought more attention to the Piping Plovers, with plover staff, park workers, law enforcement, and life guards all contributing to the effort. These collaborations will surely carry over to future seasons so that Lloyd Center efforts are that much more efficient and such an incident doesn’t occur again, productivity remains high, and Horseneck continues to be known for the success story it really is.

We thank interns Connor Worden, Nick Smith, and Heidi Cortright, as well as various volunteers for their efforts this season! Tune in next spring for shorebirds 2017!