Life in Lake Joyce is dominated by microbes. The water of Lake Joyce is nutrient-depleted and only little light makes it through the ice. The nutrient concentrations are so low in the water column that microbes remain at low concentrations, however diverse microbial communities can be found a long the bottom and the sides of the lake.
Much of the microbial communities are cyanobacterial mats and many unusual structures can be found.
Some of the structures are several centimeters tall and have a orange-purple colour. The colour is due to the production of cyanobacterial pigments that help capture light for photosynthesis.