Aquaculture America 2023

February 23 - 26, 2023

New Orleans, Louisiana USA

ENVIRONMENTAL HYPOXIA IN THE INDIAN RIVER LAGOON (IRL) AND ITS EFFECTS ON NATIVE FISH SPECIES DURING EARLY DEVELOPMENT

Magaleate Kostelnik* Alessandra Jimenez Yap, Bing Ouyang, Paul S. Wills, and Sahar Mejri

 

Harbor Branch Oceanographic Institute, Florida Atlantic University (HBOI-FAU)

5600 US 1 North, Fort Pierce, FL 34946

Email: mkostelnik2022@fau.edu

 

 



The IRL is one of the most species-diverse estuaries in North America. However, the distribution and intensity of hypoxia (low dissolved oxygen, DO) is increasing due to eutrophication, ‘dead zones’, algal blooms, etc. Effects of coastal hypoxia is well-studied in adult fish, yet gaps of information remain in terms of early life stages, including potential consequences to their development, hatching success, or future recruitment of economically important native species. These include Florida pompano, red drum, snook, Atlantic croaker, and grey snapper. To test the effects of severe hypoxia (i.e. 20% saturation, 1.4 mg/L), fertilized eggs will be incubated in two treatments (20 and 50% DO saturation, 1.4 mg/L and 3.3 mg/L, respectively) and one treatment of normoxia (100% DO saturation, 7 mg/L). Treatments will run in triplicates (n=3). Eggs and larvae will be sampled at 10, 20, 30, and 40 hours post-fertilization (hpf) to assess development, survival, and fatty acid lipids use. Lipids will be extracted from each sample and separated into neutral (used for energetic purposes) and polar (used for membranous development) fatty acids. Concentrations of these fatty acids will inform us on the potential effects of severe hypoxia on energy demand and membrane permeability (i.e., homeostatis mechanism). It is expected to see a decrease in hatch rate, survival, and overall development. This project helps increase understanding of marine ecosystem function, especially in the IRL. By investigating potential impacts of hypoxia on early larval stages, conservation and management strategies will be more well-informed and executed.