Assessing the impact of extreme flooding on survival in a southern European population of White-throated Dippers Cinclus cinclus

Abstract

ABSTRACTCapsule: There were only weak effects of winter flooding episodes on apparent annual survival of a White-throated Dipper breeding population in northern Iberia.Aims: To test whether extreme winter flooding episodes affected survival in a breeding population of White-throated Dippers Cinclus cinclus.Methods: Dippers were ringed during the breeding seasons of seven consecutive years on rivers in northern Iberia. Cormack–Jolly–Seber models were used to estimate apparent annual survival in relation to flooding during the winter periods.Results: We obtained weak evidence for an effect of flooding during the winter on the surveyed population. Two of the six winters were characterized by having an exceptionally high discharge. Our models showed that survival in the subsequent breeding period tended to be lower, although models assuming constant survival were equally well supported.Conclusion: Extreme flooding in winter may affect survival of some White-throated Dippers in northern Iberia, but its impact at the population level seems to be weak.