Nest poaching in Neotropical parrots

Timothy F. Wright, University of Maryland
Catherine A. Toft, University of California, Davis
Ernesto Enkerlin-Hoeflich, Tecnologico de Monterrey
Jaime Gonzalez-Elizondo, Tecnologico de Monterrey
Mariana Albornoz, Provita
Adriana Rodríguez-Ferraro, Provita
Franklin Rojas-Suárez, Provita
Virginia Sanz, Provita
Ana Trujillo, Provita
Steven R. Beissinger, University of California, Berkeley
A. Vicente Berovides, Universidad de La Habana
A. Xiomara Gálvez, Universidad de La Habana
Ann T. Brice, University of California, Davis
Kim Joyner, University of California, Davis
Jessica Eberhard, Princeton University
James Gilardi, Wildlife Preservation Trust International, Trinidad and Tobago
S. E. Koenig, Yale University
Scott Stoleson, Yale University
Paulo Martuscelli, Instituto Insularis
J. Michael Meyers, Patuxent Wildlife Research Center
Katherine Renton, University of Kent
Angélica M. Rodríguez, Universidad Autónoma de Chiriquí
Ana C. Sosa-Asanza, University of Georgia
Francisco J. Vilella, Mississippi State University
James W. Wiley, Grambling State University

Abstract

Although the poaching of nestlings for the pet trade is thought to contribute to the decline of many species of parrots, its effects have been poorly demonstrated. We calculated rates of mortality due to nest poaching in 23 studies of Neotropical parrots, representing 4024 nesting attempts in 21 species and 14 countries. We also examined how poaching rates vary with geographic region, presence of active protection programs, conservation status and economic value of a species, and passage of the U.S. Wild Bird Conservation Act. The average poaching rate across all studies was 30% of all nests observed. Thirteen studies reported poaching rates of ≥20%, and four reported rates of >70%. Only six studies documented no nest poaching. Of these, four were conducted on islands in the Caribbean region, which had significantly lower poaching rates than the mainland Neotropics. The other two studies that showed no poaching were conducted on the two species with the lowest economic value in our sample (U.S. retail price). In four studies that allowed direct comparison between poaching at sites with active nest protection versus that at unprotected sites, poaching rates were significantly lower at protected sites, suggesting that active protection efforts can be effective in reducing nest poaching. In those studies conducted both before and after the passage of the U.S. Wild Bird Conservation Act, poaching rates were found to be significantly lower following its enactment than in the period before. This result supports the hypothesis that the legal and illegal parrot trades are positively related, rather than inversely related as has been suggested by avicultural interests. Overall, our study indicates that poaching of parrot nestlings for economic gain is a widespread and biologically significant source of nest mortality in Neotropical parrots.