Artificial nests increase yellow-shouldered blackbird Agelaius xanthomus nesting success in Cabo Rojo and Lajas municipalities, Puerto Rico

  • Published source details López-Ortiz R., Ventosa-Febles E.A., Reitsma L.R., Hengstenberg D. & Peluca W. (2002) Increasing nesting success in yellow-shouldered blackbird Agelaius xanthomus in southwest Puerto Rico. Biological Conservation, 108, 259-263


This study is summarised as evidence for the following.

Action Category

Remove/control adult brood parasites

Action Link
Bird Conservation

Provide artificial nesting sites for songbirds

Action Link
Bird Conservation
  1. Remove/control adult brood parasites

    A study in 1996-9 in coastal forests on Puerto Rico (López-Ortiz et al. 2002) found that only a single yellow-shouldered blackbird Agelaius xanthomus nest was parasitized by shiny cowbirds Molothrus bonairensis in the study period. The authors argue that this was due to a widespread cowbird eradication programme initiated in 1984. This study is discussed in more detail in ‘Provide artificial nesting sites’.


  2. Provide artificial nesting sites for songbirds

    A replicated, controlled study in 1996-9 in coastal forests on Puerto Rico (Lopez-Ortiz et al. 2002) found that 65% of yellow-shouldered blackbird Agelaius xanthomus nests were successful in artificial nests, compared to 48% of those in natural nests. In addition, natural nests suffered higher egg loss (74% vs. 43%) and chick loss (52% vs. 22%) than artificial nests. Nests were PVC ‘elbows’ on top of fence posts, with wire baskets inside and protected from rats by a metal cone attached to the fence post. This study occurred at the same time as a shiny cowbird Molothrus bonairensis eradication programme, discussed in ‘Remove/control brood parasites’.


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