Beginning in 2016 The Taimen Fund has helped fund taimen population genetic studies throughout Mongolia. In conjunction with Dr. Sudeep Chandra of the University of Nevada, Reno, the headwaters of the Lena and the Amor in Mongolia have been sampled and analyzed. In addition The Taimen Fund has helped bridge research efforts between UNR and The Wild Salmon Center in an overall effort to genetically map taimen populations worldwide.
Scientists from UNR in coordination with fly fishing guides from Mongolia River Outfitters and Hovsgol Travel Company have used the minimally invasive technique of fin-clipping, the most widely-accepted method for collecting samples from wild fish. Once captured, fish were kept in the water in a large fishing net to ensure maximum respiration and minimal handling during the brief sampling time. A small piece was removed from the left adipose fin using surgical grade scissors dipped in ethanol, and virtually zero impact is imposed upon the fish. Each fin clip was placed into a unique 1.5 mL microcentrifuge tube containing ethanol for preservation and transport. In addition to fin-clipping, measurements were recorded including the total length and largest girth of each fish. Finally, latitude and longitude coordinates for each sample were recorded. The necessary taimen samples collected from various locations were then transported to the University of Nevada, Reno for processing.
In fall 2017, TTF and UNR collected and sequenced DNA from small fin clips taken from the pelvic fin of 56 lenok (1 from the Amur, 2 from the Onon, 7 from the Delgermoron, and 46 from the Eg) and 254 taimen (7 from the Amur, 12 from the Onon, 28 from the Delgermoron, 82 from the Tugur, 32 from the Eg, 14 from the Uur, and 79 from the greater Selenge basin), and we generated hundreds of thousands of single nucleotide polymorphisms (SNPs) using a genotyping by sequencing approach. We are pending analysis of lenok until we can obtain more samples and resources for analysis. For taimen, our preliminary analyses have produced the following results:
We see no evidence of genetic structure within river systems. Instead, we have large, unstructured populations spanning enormous basins.
We see significant genetic differentiation between river drainages, suggesting that taimen from these basins have been diverged for a very long time (>1 million years, and perhaps much longer).
We find moderate genetic structure between the Amur River drainage (Amur and Onon Rivers) and the Tugur River drainage (Tugur River), suggesting historical connectivity of these populations.
The Taimen Fund is committed to ongoing genetic population studies throughout Mongolia. Two of the four distinct river basins have been sampled and analyzed. It is our goal to have the remaining basins completed by 2020.