Snowy plovers are often sighted along local beaches during the winter months, resting up for the nesting months ahead. But the last time the birds appear to have nested in Half Moon Bay was in 2009, according to Supervising State Park Ranger Nelle Lyons.
Until then, she had observed that the birds were consistently nesting at Francis State Beach with one pair in particular always returning, even without any others.
But in their last observed season six years ago, the female went missing at some point in the four-week incubation period, Lyons said, possibly killed by a predator. While the male successfully hatched two of the three eggs on his own, the chicks never made it to the fledgling period, another four-week-long process.
“We’re always hopeful (that the birds will nest in Half Moon Bay),” Lyons said. But so far it hasn’t happened, at least to the best of Lyons’ knowledge.
“I think if (Half Moon Bay) had a successful plover nest, one of (the trained volunteers) would have found them (by now),” Lyons said.
She is aware, though, that snowy plovers have managed to nest in the past, most recently in Pescadero in 2012.
Half Moon Bay has become a less friendly nesting atmosphere for the snowy plovers, a threatened species under the Endangered Species Act. Various factors, from the increasingly narrow beaches to the resident predators like the peregrine falcons and the nonnative red foxes, have played significant roles in discouraging snowy plovers from nesting in the area, Lyons explained.
“The wider the beaches, the more (available) habitat and the more likely (that the snowy plovers will) nest,” Lyons said. “In Monterey, because (snowy plovers) have large nesting areas, they’re able to do more predator management.”
And for those reasons, combined with the temperate climate in the past few months, Monterey Bay has actually observed its earliest snowy plover nest in the last 32 years from a pair that started nesting last February, according to the biologists from Point Blue Conservation Science.
But the warmer temperatures won’t always be an advantage for this shorebird species. And, in the long term, the effects of climate change could negatively impact snowy plover populations with the disappearance of sandy, open beaches on which the birds like to nest, the conservation organization said in a statement.
For now, the local snowy plover population is actually on the rise. A winter survey, conducted on Jan. 20, reported the sighting of 152 snowy plovers over six beaches in San Mateo County, the highest number since 2004. Last year, there were only 99 birds sighted.
To help the nesting efforts, beachgoers are encouraged to watch for signs and to respect symbolic fencing that keeps foot traffic away from nests and chicks. Children and dogs should be kept from chasing shorebirds. And walking the dunes in the spring months should be limited to the water’s edge to avoid disturbing possible nesting areas.
Most plovers have a life span of about five to six years, but Lyons has observed one that lived until at least 13 years of age. Birds are often tracked through tags with color variations. And some birds seen along the San Mateo coast have originated from faraway beaches of San Diego and Oregon.