Long-Distance Breeding Dispersal of Snowy Plovers in Western North America

• Published in: The Journal of animal ecology 1994-10, Vol.63 (4), p.887-902
• Main Authors: Stenzel, Lynne E., Warriner, Jane C., Warriner, John S., Wilson, Katherine S., Bidstrup, Frances C., Page, Gary W.
• Format: Article
• Language: English
• Subjects: Animal ethology; Aves; Aviculture; Biological and medical sciences; Bird nesting; Breeding; Breeding seasons; Breeding sites; Charadrius alexandrinus; Female animals; Freshwater; Fundamental and applied biological sciences. Psychology; Male animals; Mating behavior; Nesting sites; Nesting tables; Psychology. Psychoanalysis. Psychiatry; Vertebrata
• ISSN: 0021-8790; 1365-2656
• DOI: 10.2307/5266

1. The year-round movements and nesting activities of snowy plovers that bred on the California coast in the Monterey Bay and Point Reyes areas were closely monitored between 1984 and 1989. 2. About half of 208 females and a quarter of 190 males with histories of one or more complete breeding seasons were absent from focal nesting areas for all or part of at least one breeding season. The incidence of such absences in the population was 41% in females and 16% in males, as estimated from regular nesters at the focal areas. 3. Partial-season absence was far more common than entire-season absence for regular nesters in the focal areas. Presence for partial-seasons was more common than presence for entire seasons for irregular nesters in the focal areas. 4. Of 147 plovers with any absences, 25 females and 14 males were found during the breeding season from 50 to 1140 (median = 175) km from their study area nesting sites. Positive or highly suggestive evidence of nesting at alternative locations was documented for 16 females and seven males. Movements were both north and south. We found evidence only for movements of individuals, not pairs. 5. Winter migrants were more likely than residents to make long-distance movements, a phenomenon partly attributable to birds that typically migrate to their nesting area making occasional nesting attempts on their wintering grounds. During years that the nesting season began exceptionally early at one focal area, some winterers made very early nesting attempts and in years in which they returned before July, some made late attempts in their wintering areas. 6. There was no relationship between breeding success and long-distance movement. 7. The large difference between female and male long-distance breeding dispersal rates is hypothesized to be due to the species' variable and widely spaced nesting habitat, polygamous nesting strategy, parental roles, and possibly the exercise of female mate choice.