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Providing evidence to improve practice

Individual study: Effect of pesticide treatment on tick infestation and nesting success of brown pelicans Pelecanus occidentalis on South Pelican Island and Ferry Slip Island, North Carolina, USA

Published source details

Norcross N.L. & Bolen E.G. (2002) Effectiveness of nest treatments on tick infestations in the eastern brown pelican. Wilson Bulletin, 114, 73-78


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

Remove ectoparasites from nests to increase survival or reproductive success Bird Conservation

A replicated, controlled study at two brown pelican Pelecanus occidentalis colonies in North Carolina, USA (Norcross & Bolen 2002), found that pelican chicks in nests sprayed with insecticide (1% dilution of Rabon® 50 WP applied three times during the 1998 and 1999 breeding seasons) had significantly fewer immature ticks on them, compared to those in control nests (0.4-4.2ticks/chick in 64 treated nests vs. 10.4–20.1 ticks/chick in 60 control nests). In the first year of the study, significantly more control nests were abandoned than treated nests, but there was no difference in the second study year (1998: none of 30 treated nests abandoned vs. 27% and 40% of 30 control nests on the two islands, 1999: two treated nests, three control nests sprayed with water and three undisturbed nests were abandoned). There were no significant differences in chick survival between treatment and control nests in either colony in either year.