OVERDIJK O (2004) Eurasian Spoonbill Platalea leucorodia as an 'ambassador' for protection of international flyways. LIMOSA 77 (2): 93-100.

Within NW-Europe, the Netherlands support a significant but isolated population of Eurasian Spoonbills. Although the species faced major setbacks in the past centuries (due to loss of breeding colonies and human persecution), it has made a remarkable population recovery in the past decades. The population is still thriving and ringing has shown that new colonies in the German-Danish Wadden Sea as well as settlements in France originate from Dutch Spoonbill colonies. From 1982 onwards, an increasing number of Spoonbill chicks has been ringed with individually engraved darvic rings. This projects aims to unravel the network of staging areas in the flyway between the European breeding sites and African wintering areas, in order to improve protection of Eurasian Spoonbills at the site level. In addition, population dynamics in terms of mortality and survival can be analysed.
      About 13% of the Dutch breeding population is ringed and so far about 51,000 sightings have been received, most from the Netherlands (70%), from the Atlantic coast of France (15%) and from Spain (12%; Fig. 1). Adult birds mainly move to West-Africa to winter, whereas juveniles and subadults remain relatively more in North-Africa and the Mediterranean (Fig. 2). Expeditions to West-Africa showed that 33-79% of the Dutch breeding population may be found at the Banc d'Arguin, Mauritania, in winter.
      Survival analyses by Bauchau et al. (1998) with data from the initial part of the study showed that annual survival rate of adults was 83%; for juvenile and subadult birds 32% (latter based on observations of 3rd and 4th -year birds which returned to the breeding range for the first time). Adult survival was stable over years, but seems to have improved lately (Fig. 3), perhaps due to improved protection of staging sites. Moreover, recent data suggest that subadult birds return to the breeding colonies and start to breed at an earlier age. Both 2nd -year and 3rd -year birds have been increasingly observed in the breeding colonies in the 1980s and 1990s (Fig. 4), whereas previously these birds remained in the wintering areas. The improved survival of adults and the earlier recruitment of subadult birds in the breeding population probably cause the current expansion of the population. From 2003 onwards, ringing has started in several Central and East-European countries since the flyway of this population is still imperfectly known and many staging areas are possibly under human threat.
      Winter-expeditions to Mauritania in 1997- 2001 to study wintering flocks Eurasian Spoonbills have also revealed much information on the resident 'Mauritanian' Spoonbill P.l. balsaci. During the study period, about 6000- 7000 balsaci were counted at the Banc d'Arguin. The breeding population in this area was estimated at 1800-2350 breeding pairs. Breeding success was extremely poor; in none of the years the proportion of first-year birds in the population exceeded 7%. It was observed that many colonies were raided by Common Jackals Canis aureus. Besides, predation by Slender-billed Gull Larus genei and Lesser Black-backed Gull L. fuscus was suspected. Sometimes, breeding colonies were 'suddenly' deserted during the breeding season, probably as a result of occurrence of predators near the breeding sites. In 2001 and 2002, mass-mortality occurred among both adult and juvenile birds. The causes of this phenomenon are still unknown. Eurasian Spoonbill Platalea leucorodia

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