Department of Wildlife, Fish & Conservation Biology, University of California Davis, Davis, CA, United States.
AECOM, Oakland, California, USA.
PeerJ. 2022 May 18;10:e13322. doi: 10.7717/peerj.13322. eCollection 2022.
Lahontan cutthroat trout have experienced massive declines in their native range and are now a threatened species under the US Endangered Species Act. A key management goal for this species is re-establishing extirpated populations using translocations and conservation hatcheries. In California USA, two broodstocks (Pilot Peak and Independence Lake) are available for reintroduction, in addition to translocations from wild and naturalized sources. Pilot Peak and Independence Lake fish are hatchery stocks derived from native fish from the Truckee River basin and used for recovery activities in the western Geographic Management Unit Areas only, specifically within the Truckee River basin. Yet suitability of these sources for re-introduction in different ecosystem types remains an open and important topic. We conducted growth experiments using Lahontan cutthroat trout stocked into Sagehen Creek, CA, USA. Experiments evaluated both available broodstocks and a smaller sample of fish translocated representing a naturalized population of unknown origin from a nearby creek. Fish from the Independence Lake source had significantly higher growth in weight and length compared to the other sources. Further, Independence Lake fish were the only stock that gained weight on average over the duration of the experiment. Our experiments suggest fish from the Independence Lake brood stock should be considered in reintroduction efforts.
拉洪坦鳜鱼在其原生范围内经历了大规模的减少，现在根据美国濒危物种法案，已成为受威胁物种。该物种的一个关键管理目标是利用移植和保护孵化场来重建灭绝的种群。在美国加利福尼亚州，除了从野生和归化来源进行移植外，还有两个亲鱼种群（派恩峰和独立湖）可用于重新引入。派恩峰和独立湖的鱼类是由特鲁基河盆地的本地鱼类培育而来的，仅用于西部地理管理单元地区的恢复活动，具体来说是在特鲁基河流域内。然而，这些来源在不同生态系统类型中的再引入适宜性仍然是一个悬而未决的重要话题。我们在美国加利福尼亚州的萨奇恩溪进行了拉洪坦鳜鱼的生长实验。实验评估了两个现有的亲鱼种群，以及一小部分来自附近溪流的归化种群的鱼类移植样本。与其他来源相比，来自独立湖来源的鱼类在体重和长度方面的生长速度明显更高。此外，独立湖的鱼类是唯一一种在实验过程中平均体重增加的种群。我们的实验表明，应考虑将来自独立湖亲鱼种群的鱼类纳入再引入工作中。
