Meeting Abstract
Harmful algal blooms caused by the marine microalga Aureoumbra lagunensis have been associated with fish kills as well as the loss of seagrass and benthic invertebrates in New York, Texas, and, most recently, the Indian River Lagoon (IRL) system along Florida’s east coast. Within the IRL, intertidal oyster reefs comprised of the eastern oyster Crassostrea virginica provide important ecosystem services including habitat for commercially important fishes, erosion protection, and water filtration. To determine if blooms of A. lagunensis negatively impact C. virginica, recruitment was monitored monthly beginning in May 2013 to the present on 10 oyster reefs within Mosquito Lagoon (northern IRL). Recruitment occurred continuously from May to December 2013, resuming again in February 2014. During the 2013 warm water months of April to November, maximum recruitment occurred during October (392 ± 168 live oysters/m2) and minimum recruitment during July (80 ± 48 live oysters/m2). A one-way ANOVA showed statistical significance in 2013 oyster recruitment (p<0.0001) with Tukey’s posthoc test indicating less recruitment during months with A. lagunensis present. As of September 2014, no blooms of A. lagunensis have been reported for Mosquito Lagoon. Additionally, salinity became more suitable for oyster recruitment in 2014 (≈30 ppt) than in 2013 (>40 ppt). 2014 recruitment for the month of May (the month of peak A. lagunensis densities in 2013) increased by 300% from the previous year. Depressed oyster recruitment rates were associated with presence of A. lagunensis; however, oysters in Mosquito Lagoon settled and spat (juvenile oysters) survived under brown tide conditions.
