Population Sex Ratios: Another Consideration in the Reintroduction ? Reinforcement Debate?

LAMBERTUCCI S.A,; CARRETE M; SPEZIALE K.L.; HIRALDO F.; DONÁZAR J.A

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2013 vol. 8 p. 1 - 7

1932-6203

Reintroduction or reinforcement (RorR) of wild populations is a common conservation strategy. Many conservationprojects involve the release of individuals of poorly studied species. This may lead to inefficient results or negativeimpacts on the conservation efforts. Here, we provide new insights into the conservation implications and potentialconsequences of a skew in the sex ratio of released birds and of the number of birds supplemented for thedemography of a long-lived dimorphic bird species, the Andean condor (Vultur gryphus). We demonstrate that aRorR conservation program may be less effective in conserving a species if the sex ratios of the releases and therecipient populations are not considered. We also show that releases can reduce population declines but only ifcarried out over long periods (i.e., several decades). This can mean high costs for release programs and the addedchallenge of maintaining programs over time. If RorR programs are to be implemented, bearing in mind theimportance of properly assessing their effectiveness, we urge conservation researchers and managers to considerthe implications of sex ratio biases for wild populations, and particularly for dimorphic species with sexually despoticbehaviour.