Lifelong and carry‐over effects of early captive exposure in a recovery program for Atlantic salmon (Salmo salar). (8th January 2016)

• Record Type: Journal Article
• Authors: Clarke, C. N.; Fraser, D. J.; Purchase, C. F.
• Is Part Of: Animal conservation. Volume 19:Number 4(2016:Aug.)
• Page Start: 350
• Page End: 359
• Publication Date: 2016-01-08
• Subjects: Atlantic salmon -- captive breeding -- domestication effects -- early exposure -- phenotypic plasticity -- transgenerational; Conservation biology -- Periodicals; Wildlife conservation -- Periodicals; Conservation de la biodiversité; Conservation de la faune; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 333.95416
• DOI: 10.1111/acv.12251
• Languages: English
• ISSNs: 1367-9430

Abstract

Abstract: A full life cycle understanding of how different captive rearing strategies affect wild fitness is needed for many species of conservation concern. Over the life cycle of endangered Atlantic salmon, we measured effects on wild fitness resulting from two widely applied conservation captive rearing strategies. One strategy releases juveniles before the onset of feeding (reduced exposure) and the other after 5 months of captive feeding (extended exposure). Fish were released into the wild and monitored 1–3 years later as seaward migrating juveniles. A sample of migrating fish from both rearing strategies was held captive in the ocean until mature, and artificially bred to monitor offspring viability. Extended early captive exposure resulted in smaller size‐at‐stage throughout life, shorter generation time and reduced offspring viability. Altering early captive exposure by 5 months generated long‐term and transgenerational effects on fitness and life history traits that likely accelerate domestication effects and hence provide insight into effective recovery strategy design. Abstract : Over the life cycle of endangered Atlantic salmon, we measured the effects on wild fitness resulting from two widely applied captive rearing strategies in a conservation program that releases juveniles before the onset of feeding (reduced exposure) or after 5 months of captive feeding (extended exposure). Fish were released into the wild and monitored 1–3 years later as seaward migrating juveniles. A sample of migrating fish from both rearing strategies was held captive in the ocean until mature, and artificially bred to monitor offspring viability. Extended early captive exposure resulted in smaller size‐at‐stage throughout life, less wild exposure at maturation, shorter generation time and smaller, less viable offspring in the next generation. Our results demonstrate how brief alterations in captive exposure generate long‐term effects on fitness and life history traits and hence provide insight into the effective recovery strategy design.