in the 1970’s, "dunaliella" dominated the north arm planktonic community, since the waters were too salty for other algae to thrive. the organisms were horizontally and rather randomly distributed on the surface, especially in places with minimal sunlight such as underneath rocks and logs. they were found in densities of 200-1000 cells/ml and sometimes in peak densities of 3000-10000 cells/ml. at times they were even found to be more abundant at deeper depths, though little is known on whether this was due to intolerable light intensities at the surface. even in the less saline south arm, "dunaliella" was responsible for various short-lived blooms with up to 25000 cells/ml. unfortunately, populations in both arms went into decline after periods of increased precipitations that decreased the great salt lake’s salinity. dunaliella started to become outcompeted by other phototrophs like the cyanobacterium "nodularia".