The origin and population structure of Purple Sandpipers Calidris maritima in northern France

Abstract

Biometrics of Purple Sandpipers captured in Brittany, northern France, indicated that they belonged to a long-billed population, so may have originated in Canada or Russia. There was a preponderance of males (81%). An uneven sex ratio in favour of males is proving to be the norm for winter populations of Purple Sandpiper. A high percentage of captures were of first-year birds. This was probably biased by the catching methods (mist-netting and dazzle-netting), because a lower value was obtained by observing free-living birds.