http://www.nanfa.org/ac/slender-madtom-rock-lake-wi.pdf
We still don’t know quite what to make of our discovery. Finding
a new population of a rare fish species is always exciting. But find-
ing the population in a completely atypical and unexpected spot
can be a bit disconcerting. It calls into question what you think you
know about the biology and habitat preferences of the species and,
in a larger sense, your competence as a naturalist. Such was the case
when we found Slender Madtom Noturus exilis in Rock Lake, Wis-
consin (Figure 1), to our knowledge the first and only population of
this normally flowing-water fish species from a natural lake.