A rare and unique perspective on the impact of Glacial Lake Missoula on life in the surrounding mountains has been offered by Professor Emeritus Gary Belovsky of Notre Dame.  An object of his studies is a previously unidentified shield-backed katydid (Tettigoniidae: Steiroxys sp.) cricket insect, found on what had been Lake Missoula islands in the Mission Valley and in the Mission Mountains. Based on years of field research (since 1978) in the Bison Range and Mission Valley he found that this remarkable insect occurs in the areas that, during the last major ice-age advance, were islands isolated by the surrounding waters of Glacial Lake Missoula.

This diurnal large-bodied insect herbivore (1 – 1.5 gram adult females) can attain relatively high densities (0.35/m ² ) in mountain meadow habitats. This insect can attain even higher densities in drier prairie habitats, but due to high bird predation they do not occur in these more open habitats. Therefore, the more open lower elevation grasslands act as a barrier to the dispersal of these insects between the surrounding mountains that were formerly isolated islands in Glacial Lake Missoula.

Another interesting characteristic of this species, is the absence of males, but that’s another story.