At the tail end of the snowy plover breeding season, Point Reyes National Seashore ecologists have good news to report. The last month was the most productive of the summer: Park staffers announced the appearance of two broods near Abbotts Lagoon that had hatched from nests they didn’t know about. It could signify that the initial count of 32 nests this summer, down from 39 last year, was low. Within a few weeks, the breeding season will be over. “It is typical that we’re most successful at the end of the season, and even more so this year, as it turns out,” said Dave Press, the park’s wildlife ecologist. “We’re having a great year.” The seashore partners with Point Blue Conservation Science to protect the snowy plover population and restore habitat along the coast. Snowies are federally threatened—only about 2,500 of the birds are estimated to live on the Pacific Coast—so the park is obligated to protect them. Ecologists also treat the species as an indicator of the health of beaches and the coastal ecosystem. Shorebirds like snowies thrive when undersea kelp forests are healthy because they forage for insects in the wrack zone, the line of seaweed and other debris deposited on the shore at high tide. “The beach as nesting habitat is unique,” Mr. Press said. “They’re tied to the entire near shore ecosystem, just through their foraging habits.” Beach activities and development threaten the birds during their breeding season, which coincides with peak summer activity on the coast. A stretch of sand between the North Beach parking lot and the mouth of Abbotts Lagoon will remain closed every weekend until Labor Day to prevent human disturbance to nesting areas.