Abstract
Macroinvertebrates were collected and identified to the genus level from ten sites at Green Lake, Fayetteville, NY. Green Lake is a meromictic plunge pool formed 11,000 years ago by a glacial waterfall. Due to the nature of its creation it has a very unique benthic habitat for macro invertebrates. The data collected were compared to three local lakes of varying human disturbance, Onondaga lake (most disturbed), Otisco Lake (mildly disturbed) and Cazenovia Lake (least disturbed). The comparison of Green Lake to Onondaga Lake is especially appropriate because they both have very high specific conductance levels (2,470 μS/cm and ~1,600 μS/cm, respectively). Genera richness did not differ between Green and Onondaga Lakes or between Green and Otisco Lakes. Green Lake had greater COTE (Coleoptera, Odonata, Trichoptera and Ephemeroptera) richness and number of intolerant taxa than Onondaga Lake according to the nonparametric Kruskal-Wallis test and post hoc Dunn's test. The differences could be caused by differing lake morphology or habitat types in each lake. Both Onondaga Lake and Green Lake have high conductivity levels relative to Cazenovia and Otisco Lakes, but the conductivity in each lake is driven by different ions (Green lake: Ca2• and So/ · Onondaga Lake: Cl"). The difference in ions in each lake may cause the changes observed.