By Request, GSI Data For Notropis Asperifrons And N. Stilbius

By request from Andrew in a Comment to the last posting, here are GSI figures for Notropis asperifrons (burrhead shiners) and N. stilbius (silverstripe shiners) from Borden Creek in the Sipsey Wilderness of Alabama. The first graph is males, and the second is females, of the two species. Silverstripes are near relatives of telescope shiners, so the comparison is interesting. We have found much higher peak GSI values for both males and female telescopes than for silverstripes, and differences in reproductive timing: silverstripes peak in May, telescopes peak in June. And, in a slight twist, the burrheads have a reproductive peak in April, probably one way that two similar species partition the environment of a fairly small creek. In the graphs below, the small numbers represent the sample size for each month's average.

I guess one could do this in a really big way with a bunch of shiner species from around the region and discern apparent patterns. Maybe as interesting would be doing it for a given species in a given stream over several years, and see if the patterns hold steady or do they vary interannually as environmental conditions might vary. I honestly don't know the answer, maybe that's a graduate thesis or dissertation waiting to happen. But I'll continue to serve in my own way, too.