Aflezingen van gekleurringde Zilvermeeuwen Larus argentatus en Kleine Mantelmeeuwen Larus fuscus in Nederland

Several colour-ring programmes became established in The Netherlands, to monitor the dispersal, migration routes, use of foraging areas, annual survival, return rates and other parameters of Herring Gulls Larus argentatus and Lesser Black-backed Gulls L. fuscus. One of the more comprehensive studies was launched in the mid-1980s and this involved the annual ringing of c. 100 fledglings in 12 (later 14) colonies of Herring Gulls scattered along the Dutch coastline between 1986 and 1988. Nearly 90 000 documented sightings of Herring Gulls ringed in these years have been processed and are currently available for analysis. The current status of this and other ringing schemes in The Netherlands is described, some preliminary results are provided, and observers are kindly asked to continue reporting documented sightings, even if some schemes are seemingly discontinued with co-ordinators failing to provide life-histories to the observers. In several of the long-running schemes, gulls are monitored that are well over 20 years of age and scheme continuation is of great significance to enhance our understanding of the life-history of these long-lived seabirds.