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Résumé :
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Creating self-sustaining populations resilient to stochastic events is the goal of conservation reintroductions. Concern about disrupting locally co-adapted gene complexes, outbreeding depression, and hybridization has led to a "local is best paradigm" for source selection, yet this policy constrains rare plant reintroduction efforts and may not always best conserve rare species. Using progeny from controlled crosses (control, selfed, near neighbor, far neighbor and between sites) with maternal plants from two sites, we tested survival and population trajectories of US endangered Jacquemontia reclinata reintroduced in 2004 and 2005 to three sites. By 2011, survival and recruitment was greatest for mixed-population progeny, was consistent across years, and became most apparent after extreme climate events (hurricanes, drought, and exceptional cold). Populations founded from mixed sources exhibited greater resilience to stochastic disturbances than those from a single source and had positive projected population growth at two of three sites. Recipient sites most proximal to maternal origin were not those with best survival. Maximizing reintroduced population persistence calls for re-examining paradigms, using decision trees and reintroduction guidelines to guide source selection choices. The local is best paradigm may be dooming many reintroductions to failure. (C) 2012 Elsevier Ltd. All rights reserved.
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