At the end of August 2017, Jim Hood, Susan Curless, and collaborators at Saint Catherine's University and the Icelandic Institute for Freshwater and Marine Fisheries measured primary production in Lagarflöt. Lagarflöt, a glacial lagoon in Northeastern Iceland, has experienced a 50% decline in water transparency due to hydroelectric water diversions. Our group is working to better understand how these changes in transparency shape the quantity and spatial distribution (benthic versus pelagic) of energy available to higher trophic levels.