Adult piping plover habitat selection varies by behavior

Piping plovers (Charadrius melodus, “plover”) are beach-nesting shorebirds that occupy their breeding range from about April to August. When plovers arrive on the breeding grounds, they select and defend territories, lay and incubate eggs, and tend to precocial broods; additionally, adults can return to a non-breeding stage after final nest failure or after chicks have fledged or died. We hypothesized that habitat selection would differ among these phases of the breeding cycle because the needs of the birds differ among them. We monitored plovers on Fire Island and Westhampton Island, New York, during 2016– 2018, recording individual locations of adult birds. We used resource selection functions to determine whether breeding stage (pre-breeding, nesting, brooding, post-breeding), breeding status (breeding, nonbreeding), or instantaneous behavior class (parental [incubating, brooding, and accompanying chicks], non-parental [all other behaviors]) best explained relationships with landscape characteristics known to be important to breeding plovers. Differences in habitat selection between adults exhibiting parental behaviors and non-parental behaviors had the greatest support in our model set. Compared with non-parental plovers, plovers displaying parental behavior selected areas closer to bay intertidal habitats and with proportionally more dry sand in the surrounding landscape than other habitat types. Non-parental plovers avoided areas with more dry sand and did not select for or against bay intertidal habitats. Additionally, non-parental plovers avoided development and higher elevation areas more than parental plovers, although both exhibited avoidance of these features. The total amount of suitable habitat ranged from 100.14 ha to 151.07 ha. In each year, there was more suitable habitat for parental plovers (129.57–151.07 ha) than non-parental plovers (100.14–108.83 ha). Due to these differences, when improving, creating, and protecting plover habitat, managers should consider habitat needs of both behavioral classes. Habitat management for nesting and brooding plovers should focus on maintaining vegetation-free sand and access to foraging habitat, and habitat management for non-parental plovers should focus on flat, low-elevation foraging habitats, particularly areas further from development.