HYPOXIA CHALLENGES IN ESTUARINE ENVIRONMENTS: EFFECTS ON EARLY FISH DEVELOPMENT AND LIPID UTILIZATION

The distribution and intensity of hypoxia (low dissolved oxygen, DO) is increasing due to eutrophication and algal blooms in estuaries like those in the Gulf of Mexico and the Indian River Lagoon. The objective of this study is to determine how low DO affects the development and lipid utilization of the Florida Pompano (Trachinotus carolinus) and Red Drum (Sciaenops ocellatus). Fertilized eggs were incubated in two DO hypoxia treatments: severe (20% DO saturation, 1.6 mg/L), moderate (50% DO saturation, 3.9 mg/L), and normoxia (100% DO saturation, 7.6 mg/L). Eggs and larvae were sampled at 24-hours post-fertilization to assess hatch survival, larval development, and fatty acid (FA) lipids utilization. Results suggest hypoxia significantly impacts Florida Pompano development, with polar FAs most affected, while Red Drum shows greater tolerance to low DO. These findings provide insight into early fish larval stages to improve conservation and management strategies for their recruitment.