Gonçalves da Silva Anders, Appleyard Sharon A, Upston Judy
CSIRO Oceans and Atmosphere Flagship, GPO Box 1538, Hobart, TAS, 7001, Australia; School of Biological Sciences, Monash University, 18 Innovation Walk, Clayton, Vic., 3800, Australia.
Mol Ecol. 2015 Feb;24(3):564-79. doi: 10.1111/mec.13046.
Identifying fish stock structure is fundamental to pinpoint stocks that might contribute colonizers to overfished stocks. However, a stock's potential to contribute to rebuilding hinges on demographic connectivity, a challenging parameter to measure. With genomics as a new tool, fisheries managers can detect signatures of natural selection and thus identify fishing areas likely to contribute evolutionarily compatible colonizers to an overfished area (i.e. colonizers that are not at a fitness disadvantage in the overfished area and able to reproduce at optimal rates). Identifying evolutionarily compatible stocks would help narrow the focus on establishing demographic connectivity where it matters. Here, we genotype 4723 SNPs in 616 orange roughy (Hoplostethus atlanticus) across five fishing areas off the Tasmanian coast in Australia. We ask whether these areas form a single genetic unit, and test for signatures of local adaptation. Results from amova, structure, discriminant analysis of principal components, BAYESASS and isolation by distance suggest that sampled locations are subjected to geneflow amounts that are above what is needed to establish 'drift connectivity'. However, it remains unclear whether there is a single panmictic population or several highly connected populations. Most importantly, we did not find any evidence of local adaptation, suggesting that the examined orange roughy stocks are evolutionarily compatible. The data have helped test an assumption of the orange roughy management programme and to formulate hypotheses regarding stock demographic connectivity. Overall, our results demonstrate the potential of genomics to inform fisheries management, even when evidence for stock structure is sparse.
识别鱼类种群结构是确定哪些种群可能为过度捕捞种群提供定居者的基础。然而，一个种群对种群恢复做出贡献的潜力取决于种群动态连通性，这是一个难以测量的参数。作为一种新工具，基因组学可以帮助渔业管理者检测自然选择的特征，从而识别可能为过度捕捞区域提供进化上兼容的定居者的捕捞区域（即那些在过度捕捞区域没有适应性劣势且能够以最佳速率繁殖的定居者）。识别进化上兼容的种群将有助于缩小关注范围，将重点放在建立关键的种群动态连通性上。在此，我们对澳大利亚塔斯马尼亚海岸外五个捕捞区域的616条橙棘鲷（Hoplostethus atlanticus）中的4723个单核苷酸多态性（SNP）进行了基因分型。我们探究这些区域是否形成一个单一的遗传单元，并测试局部适应性的特征。方差分析（amova）、结构分析、主成分判别分析、BAYESASS以及距离隔离分析的结果表明，采样地点的基因流水平高于建立“漂变连通性”所需的水平。然而，目前尚不清楚是否存在一个单一的随机交配种群或几个高度连通的种群。最重要的是，我们没有发现任何局部适应性的证据，这表明所研究的橙棘鲷种群在进化上是兼容的。这些数据有助于检验橙棘鲷管理计划的一个假设，并就种群动态连通性提出假设。总体而言，我们的结果表明，即使在种群结构证据稀少的情况下，基因组学也有潜力为渔业管理提供信息。
