Here it is another year and we’re still searching for slender chubs, Erimystax cahni! This extremely rare minnow was last seen in the Clinch and Powell Rivers in the upper Tennessee drainage. One specimen was seen in the mid ’90s in the Clinch and a few others were collected in the late ’80s. In the Powell, they have not been seen since the early ’80s. So, the question is….are they gone? We’re betting that they are     still persisting somewhere in the Clinch or Powell, but probably in very low numbers. They are big river fish and can be somewhat difficult to collect (even when they were definitely still around).  

Dave Etnier, in one of the only theoretical presentations I’ve ever seen him give, suggested that certain rare fishes have a tendency to cycle in their abundance. When the low end of the cycle falls below a particular point, those fish are no longer detectible (at least not easily). Specimens may start showing up again at some point in the future, but until that time, they can appear to have disappeared altogether (my apologies, Ets, if I’ve butchered your theory). We can only hope that this is what’s happening with the slender chubs! 

Our goal is to be able to start a captive propagation program and begin to augment (or restore) populations in the Clinch and Powell. Several years ago we began working with some of the closest relatives of the slender chub, the streamline and blotched chubs, E dissimilis and E insignis, respectively. We successfully spawned and reared both species. Our hope is that the slender chubs have a similar mode of reproduction and can similarly be reared in our hatchery. But, first we have to find some!

Erimystax dissimilis

  Erimystax insignis

This week, we are headed out again to the Clinch, and maybe Powell rivers. Two weeks ago, we were collecting in the Clinch at Kyles Ford, a popular collecting site now owned by the Nature Conservancy. We found no slender chubs, however, we did turn up a fish that might be considered even rarer in the upper Tennessee drainage! We collected a single western sand darter, Ammocrypta clara! This is the first one any of us there had ever seen!

The following day, we took our crew to the Powell River in search of slender chubs. Once again, no luck! But here, we managed to pick up another couple of rare fish, two yellowfin madtoms, Noturus flavipinnis.

 These were collected at Brook’s bridge in Tennessee. One specimen was taken from that site last year. The two we saw there this year were young specimens, one last years’ reproduction and one from the previous year. The fact that these were taken relatively easily coupled with the fact that several have been seen over the past few years, gives us reason to hope that this population is on the rebound (at least in some areas of the Powell). Up until a few years ago, only three specimens had ever been collected in the Powell River! Even now, probably fewer than 15 have ever been seen there!

 The yellowfin madtom and the western sand darter are probably both species that fall into Etnier’s cyclical population theory. Both of these have been thought extirpated at one time or another. Hopefully, we will be able to say the same thing about the slender chub soon!

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