Bogdanowicz Wiesław, Rutkowski Robert, Gabrielyan Bardukh K, Ryspaev Akylbek, Asatryan Anzhela N, Mkrtchyan Jon A, Bujalska Barbara M
Museum and Institute of Zoology, Polish Academy of Sciences, Warszawa, Poland.
Scientific Center of Zoology and Hydroecology, National Academy of Sciences of Armenia, Yerevan, Armenia.
PLoS One. 2017 Jul 6;12(7):e0180605. doi: 10.1371/journal.pone.0180605. eCollection 2017.
The Soviet Union played the leading role in fish introductions in Eurasia. However, only 3% of all introductions prior to 1978 gave a commercial benefit. One of the noteworthy examples appears to be the Sevan trout (Salmo ischchan Kessler, 1877)-an endemic salmonid of Lake Sevan in Armenia. This species has been introduced to Kirghizstan, Kazakhstan, and Uzbekistan, however, only the Kirghiz population has persisted in relatively high numbers. In this paper we provide the first extensive molecular study of S. ischchan using samples from the native population from Lake Sevan and three hatcheries in Armenia, as well as from the population introduced to Lake Issyk Kul in Kirghizstan. The Kirghiz population has been isolated since the introductions took place in 1930 and 1936. Our results, based on 11 nuclear microsatellites and a 905 bp fragment of the mitochondrial control region suggest that hatcheries have maintained genetic variability by way of ongoing translocations of individuals from Lake Sevan. Simultaneously, significant Garza-Williamson M-values suggest that bottlenecks could have reduced the genetic variability of the wild populations in the past. This hypothesis is supported by historical data, indicating highly manipulated water-level regulations and poaching as two main factors that dramatically impact fish abundance in the lake. On the other hand, a similar situation has been observed in Kirghizstan, but this population likely rebounded from small population size faster than the other populations examined. The Kirghiz population is significantly genetically differentiated from the other groups and have morphological features and biological attributes not observed in the source population. Genetic data imply that the effective population size in the native population is lower than that found in the introduced population, suggesting that some active protection of the Lake Sevan population may be needed urgently.
苏联在欧亚大陆的鱼类引进中发挥了主导作用。然而，1978年以前所有引进的鱼类中只有3%带来了商业效益。一个值得注意的例子似乎是塞凡湖鳟（Salmo ischchan Kessler，1877年）——亚美尼亚塞凡湖的一种地方性鲑科鱼类。该物种已被引入吉尔吉斯斯坦、哈萨克斯坦和乌兹别克斯坦，但只有吉尔吉斯斯坦的种群数量相对较多。在本文中，我们首次对塞凡湖鳟进行了广泛的分子研究，使用了来自塞凡湖本地种群、亚美尼亚三个孵化场以及引入吉尔吉斯斯坦伊塞克湖的种群的样本。吉尔吉斯斯坦的种群自1930年和1936年引进后就一直处于隔离状态。我们基于11个核微卫星和线粒体控制区的905 bp片段得出的结果表明，孵化场通过持续从塞凡湖转移个体来维持遗传多样性。同时，显著的Garza-Williamson M值表明，过去瓶颈效应可能降低了野生种群的遗传多样性。这一假设得到了历史数据的支持，这些数据表明高度人为的水位调节和偷猎是严重影响该湖鱼类数量的两个主要因素。另一方面，在吉尔吉斯斯坦也观察到了类似情况，但这个种群可能比其他被研究的种群更快地从较小的种群规模中恢复过来。吉尔吉斯斯坦的种群在基因上与其他群体有显著差异，并且具有在源种群中未观察到的形态特征和生物学属性。遗传数据表明，本地种群的有效种群大小低于引进种群，这表明可能迫切需要对塞凡湖种群进行一些积极的保护。
