La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Titre :	Recent Snowy Plover population increase arises from high immigration rate in coastal northern California (2017)
Auteurs :	Mark A. Colwell, Auteur ; Elizabeth J. Feucht, Auteur ; Matt J. Lau, Auteur ; David J. Orluck, Auteur ; Sean E. Mcallister, Auteur ; Amber N. Transou, Auteur
Type de document :	Article
Dans :	Wader Study (124(1) April, 2017)
Article en page(s) :	40-48
Résumé :	The Pacific coast population of the Snowy Plover Charadrius nivosus nivosus is listed as threatened under the U.S. Endangered Species Act, which requires demographic data to inform management directed at increasing the population. Accordingly, we summarized a 16-year dataset on population size and growth, return rates, and productivity of a color-marked breeding population in coastal northern California, one of six recovery units for the listed population. The geographically isolated population varied annually in size (19-74 breeding adults), with an early nine-year decline (lambda = 0.92 +/- 0.30) followed by a seven-year increase (lambda = 1.22 +/- 0.19). Overall, productivity averaged 0.85 +/- 0.29 chicks fledged per male, which is well below that identified by viability analyses to maintain the population. Adult return rates, an index of survivorship, varied greatly among years (30-95%). Immigrants comprise 63 +/- 5% of the population over the past

Lundi , mardi et jeudi de 9h à 12h et de 13h à 17h00 : ouverture au public ...