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Providing evidence to improve practice

Individual study: The effects of anthelminthic treatment on parasite infection and fledging success of Eurasian oystercatcher Haematopus ostralegus chicks on Schiermonnikoog, Friesland, the Netherlands

Published source details

Van Oers K., Heg D. & Le Drean Quenec'hdu S. (2002) Anthelminthic treatment negatively affects chick survival in the Eurasian oystercatcher Haematopus ostralegus. Ibis, 144, 509-517


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Remove/treat endoparasites and diseases Bird Conservation

A randomised, replicated and controlled trial in 1996 on an island in the northern Netherlands (Van Oers et al. 2002) found that fledging success of Eurasian oystercatcher Haematopus ostralegus broods was significantly lower when chicks were treated with anthelminthic drugs, compared to controls (18-20% success for treated broods vs. 29-38% for controls). This was despite there being no significant differences in clutch size or hatching success between groups and treated hatchlings having significantly lower incidence of gut parasites (41% of 17 treated chicks infected vs. 60% of 20 untreated chicks). The authors suggest that interference with chicks’ immune systems could have driven this pattern.