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Auteur (up) Henry, P.-Y.; Ollivier, P. url  doi
  Titre Low immigration and high local recruitment in an isolated, coastal population of a declining grassland passerine, the Northern WheatearOenanthe oenanthe Type Article scientifique
  Année 2015 Publication Acta Ornithologica Revue Abrégée Acta Ornithologica  
  Volume 50 Numéro 2 Pages 193-203  
  Mots-Clés apparent survival, coastal grassland, demography, dispersal distance, habitat fragmentation, immigration, local extinction, local population dynamics, local recruitment  
  Résumé The western European populations of Northern Wheatear Oenanthe oenanthe have halved over the past two

decades. In this context of increasingly fragmented populations, a key issue is to understand the role of immigration in

the maintenance of remnant populations. We characterized the local survival, fecundity, recruitment and immigration

rates of a small, geographically isolated, coastal French population during a period of population stability, while the

regional population was rapidly decreasing (19911999). Annual local adult and juvenile survival rates were estimated

with capture-resighting data at, respectively, 0.463 ± 0.052 (n = 157 adults) and 0.215 ± 0.054 (n = 363 nestlings). Only

2.1 immigrants joined the population per year (7.3% of all recruits). This annual immigration rate (0.039) is lower than

all 14 available estimates for small to medium-sized birds. The local population growth rate depended equally on all

demographic parameters, apart from a minor influence of the immigration rate. Within-site breeding dispersal distances

were low, and differed between sexes (78 ± 49 m for males, 259 ± 274 m for females). Juvenile and adult survival

rates appeared lower than for populations of wheatears settled in high quality habitats, but this deficiency was compensated

by high fecundity and the 2 annual immigrants. The small population size (2227 pairs), extremely low immigration,

and strong dependence on local recruits suggest that this population was demographically isolated on a patch

of moderate habitat quality, with no chance of rescue by immigration in case of stochastic event. Indeed, this population

went extinct in the 2000s, after a disturbance of unknown origin.
  Auteur institutionnel Thèse  
  Editeur Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0001-6454 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MNHN @ henry @ collection 1376  
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