Collaborative Research: Ecological Correlates of Introgressive Hybridization Between Native and Introduced Populations of Salmonid Fishes

这项建议侧重于引入非本地虹鱼(Oncorhynchus Mykises)对受威胁的黄石切喉鲑鱼(O.clarki buvieri)的本地基因库的生态和遗传影响。除了引入物种的竞争、捕食和引入疾病生物外，对一些本地鱼类物种来说，一个主要威胁是与引入物种的杂交。杂交种如果能繁殖，就会传播，并导致引入物种的亲本基因完全替换。这项研究旨在确定黄石切喉鲑鱼和彩虹鲑鱼之间的杂交程度，以及在当地基因库中发生的遗传稀释程度。此外，研究还将测试环境的特定特征(温度、海拔、溪流等)。与纯物种或杂交种的存在与否相关。通过这种方式，这项研究将确定特定的环境是否有利于杂交鱼类的传播，或者为黄石切喉鱼剩余的纯种群提供优势。这项研究将提供关于虹鱼遗传入侵模式的第一份文献，并开始探索导致这种模式的生态机制。如果找到与环境相关的因素，可以预测本地黄石公园的鲑鱼比杂交鲑鱼成功，这样的栖息地可以被放在保护的首要位置。只有通过综合理解影响入侵物种成功的生态和遗传因素，我们才有希望阻止它们的传播并拯救本土基因库。

This proposal focuses on the ecological and genetic impacts of the introduction of non-native rainbow trout (Oncorhynchus mykiss) on native gene pools of threatened Yellowstone cutthroat trout (O. clarki bouvieri). In addition to competition, predation and the introduction of disease organisms by introduced species, for some native fish species, a major threat is that of hybridization with the introduced species. Hybrids, if fertile, can spread and cause the complete replacement of parental genes with those of the introduced species. This study is designed to determine the extent of hybridization between Yellowstone cutthroat trout and rainbow trout as well as the degree of genetic dilution that has occurred in native gene pools. In addition, the study will also test whether particular features of the environment (temperature, elevation, stream flow, etc.) are correlated with the presence or absence of pure species or hybrids. In this manner, the study will determine if particular environments favor the spread of hybrid fishes, or provide an advantage to the remaining pure populations of Yellowstone cutthroat trout.This study will provide the first documentation of the pattern of genetic invasion of rainbow trout and begin to explore the ecological mechanisms that are responsible for this pattern. If environmental correlates are found which predict the success of native Yellowstone cutthroat trout over hybrids, such habitats can be given top priority for conservation. Only through a combined approach of understanding both the ecological and genetic factors that influence the success of invasive species, can we ever hope to deter their spread and save native gene pools