Diatoms are a longstanding indicator for the Great Lakes and were a large component of the Great Lakes EMAP program, but they are still often overlooked. Diatoms are very diverse and occur both on substrates and in the water column. Gene Stoermer, Russ Kreis, and Norman Andresson recently published a checklist of Great Lakes diatoms: There are 1500 species occurring across the Great Lakes. We may find new species in coastal wetlands.

(Stoermer, E., R. Kreis, and N. Andresen. 1999. Checklist of Diatoms from the Laurentian Great Lakes. II. Journal of Great Lakes Research 25(3): 515-566.)