California coastlines include some of the most picturesque landscapes anywhere on earth. Popular destinations for beach recreation, these coastal areas also support a diverse range of wildlife, from marine mammals to hundreds of migratory and resident bird species.
Spring and summer are busy times of the year for both beach-goers and wildlife along the California coast. The warm, dry season marks the kick off for breeding season for many bird species, and for some, like the California least tern (Sterna antillarum browni) and Pacific Coast population of the Western snowy plover (Charadrius nivosus nivosus), a successful breeding season is crucial for the species’ long-term survival.
The federally endangered California least tern and federally threatened Pacific coast population of Western snowy plover are protected under the Endangered Species Act (ESA). Their ability to recover and maintain self-sustaining populations depends, in large part, on the protection of important habitats along the Pacific coast where they feed and reproduce.
Many beach activities, from kite-flying to dog-walking, can disturb these nesting birds, causing the adults to abandon their nests and leave their eggs or chicks vulnerable to foxes, crows, ravens and other predators.
“Because the birds are so small, particularly in the case of the plover, and their eggs the same coloring as the sand, they can be particularly difficult to spot with the naked eye. This makes them especially vulnerable to the impacts of human disturbance,” said Bill Standley, fish and wildlife biologist with the U.S. Fish and Wildlife Service’s (Service) in Ventura.
Standley works with land managers and conservation partners along the southern and central California coast, from California State Parks to federal landowners, to minimize impacts to the birds during this critical time of year.
Where known breeding sites occur, some land managers install temporary fencing and signage to direct visitors around nesting areas. Many of these designated areas still provide public access while protecting nesting areas closer to the coastal dunes and salt flats.
“Temporary fencing not only provides protection for nesting plovers and terns, but also for many other species of invertebrates and plants, and the larger coastal ecosystem upon which they depend,” said Alexis Frangis, environmental scientist with California State Parks. Frangis works with a team of state biologists and staff to install the temporary fencing on State Park lands, including McGrath State Beach in Ventura, where the birds are known to nest.
“We strive to achieve a balance between natural resource protection and outdoor recreation,” she said.
And so far, these efforts to protect the birds during breeding season are paying off. The Service, in coordination with California Department of Fish and Wildlife, Point Blue Conservation Science, California State Parks, and other partners, conducts surveys at the local, state and range-wide levels to gauge population trends for these at-risk species. When viewed over time, these population surveys give land managers insights into recovery action implementation, aimed at reducing threats that impact these birds.
“The surveys allow us to evaluate the effectiveness of specific management efforts, and determine how individual breeding sites are contributing to the overall population. Ultimately, our objective is to recover the species by having a self-sustaining population,” said Jim Watkins, biologist with the Service’s Arcata office
Watkins, who coordinates range-wide recovery efforts for the Western snowy plover in coastal Washington, Oregon and California, notes that there have been some short-term population declines, primarily attributed to unseasonably cold winters and site-specific predation. However, surveys indicate an overall upward trend, indicating that management efforts are working. For the Pacific Coast population of Western snowy plovers in California, current estimates are between approximately 2,170 and 2,270 individuals, compared to 1,780 in the early 1990s.
The estimated number of California least terns has increased from 600 pairs when listed in 1970 to more than 4,900 pairs in 2014.
Biologists say the overall upward trends for both species are a result of efforts to protect nesting birds, predator management, habitat restoration, and outreach programs to increase awareness of the species’ plight among beach-goers and local communities.
In addition to establishing ESA protections for the Pacific Coast population of Western snowy plover and California least tern, the Service also established Recovery Plans in concert with land managers and conservation agencies to provide recommended steps and actions to help boost populations over time.
“The ultimate goal is to recover the species to sustainable levels to the point that they no longer need protection under the ESA,” Standley said.
A Share the Shore education campaign was also initiated by California Audubon Society to encourage beach-goers and local communities to learn about these at-risk species and their importance to overall coastal ecosystems. Volunteer docents offer their time to help monitor the birds during the nesting season, and educate beach-goers about activities that could disturb nesting activities. Service biologists take school groups on beach nature hikes to learn about plovers, terns and other native wildlife, and California State Parks offers training opportunities every spring for volunteers interested in becoming beach docents.
Building on these past successes, the Service and conservation partners will continue to implement habitat restoration efforts including removal of invasive plants from beaches and dunes to improve nesting habitat. Wildlife managers and researchers also continue to investigate ways to reduce predation and disturbance at nesting sites.
“Effective conservation of at risk-species like the California least tern and Western snowy plover demands collaboration, sound science, and education,” Watkins said. “Looking forward, by leveraging our resources to restore habitat, reduce threats and educate the public, we are giving these species a fighting chance against extinction.”
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Did you know?
Western snowy plover breeding season extends from March through September, while the breeding window for California least extends from April through August. Western snowy plovers and California least terns nest on the dry-sand portions of beaches, coastal dunes, estuaries, river bars, and salt ponds, and make small indentations in the sand or surface to form their nest.
Expansive urban development, the introduction of non-native vegetation, and an increase in beach predators like crows and ravens contributed to the Western snowy plover’s decline and classification as threatened by the U.S. Fish and Wildlife Service in 1993. Similar threats led to the decline of the California least tern, which was designated as federally endangered in 1970.