Fledging success of wader chicks, estimated from ringing data

Abstract

From 1976 to 1985 large numbers of chicks of Lapwing Vanellus vanellus, Black‐tailed Godwit Limosa limosa, Redshank Tringa totanus, and Oystercatcher Haematopus ostralegus have been aged during ringing in The Netherlands in a large scale programme involving many volunteers. Hatching dates have been calculated from ringing dates (corrected for estimated age at ringing). Distributions of hatching dates in the province of Frisia differ from elsewhere, because of egging (Lapwing eggs are taken), and the associated activities of nest protection. Hatching dates of Frisian Lapwing are strongly synchronised, not only because of a peak in replacement clutches after the closing of the egging season, but also as a result of nest protection, which precludes the occurrence of many late replacement clutches. Synchronisation also characterizes the other species. Age‐specific recovery rates from the same material have been used to estimate fledging success. Fledging success in the Lapwing may be positively correlated wit...