|Document Type:||Journal Article|
|Title:||Effectiveness of managed gene flow in reducing genetic divergence associated with captive breeding|
|Author:||Charles D. Waters, Jeffrey J. Hard, M. S. O. Brieuc, D. E. Fast, Kenneth I. Warheit, Robin S. Waples, Curtis M. Knudsen, W. J. Bosch, Kerry A. Naish|
|Keywords:||captive breeding,adaptive divergence,managed gene flow,genotyping,sequencing|
Captive breeding has the potential to rebuild depressed populations. However, genetic changes associated with captive breeding may decrease restoration success and negatively affect the adaptive potential of the entire population. Thus, approaches that minimize genetic risks should be tested in a comparative framework over multiple generations. Genetic diversity in two captive-reared lines of a species of conservation interest, Chinook salmon (Oncorhynchus tshawytscha), was surveyed across three generations using genome-wide approaches. Genetic divergence from the source population was minimal in an integrated line, which used only naturally-derived adults for reproduction, but significant in a segregated line, which bred only captive-origin individuals. Estimates of effective number of breeders revealed that the rapid divergence observed in the segregated line was largely attributable to genetic drift. Three independent tests for signatures of adaptive divergence also identified temporal change within the segregated line, providing possible evidence of domestication selection. Our results empirically demonstrate that using naturally-born individuals as parents for a captive-reared population reduces genetic divergence over the short term compared to one that relies solely on captive-origin parents. These findings complement existing studies of captive breeding, which typically focus on a single management strategy and examine the fitness of one or two generations.
|Theme:||Recovery and rebuilding of marine and coastal species|
Evaluate the effects of artificial propagation on recovery, rebuilding and sustainability of marine and anadromous species.