Effects of hypoxia, and the balance between hypoxia and enrichment, on coastal fishes and fisheries

This threshold suggests that habitat quality for the demersal fish assemblage begins to be reduced at values above 2 mg l-1 (the typical definition for hypoxia), as fish exhibit elevated respiration and metabolism, reduced growth, or other signs of physiological stress that drive mobile animals to emigrate from the affected area.

“This threshold suggests that habitat quality for the demersal fish assemblage begins to be reduced at values > 2 mg l -1 (the typical definition for hypoxia), as fish exhibit elevated respiration and metabolism, reduced growth, or other signs of physiological stress that drive mobile animals to emigrate from the affected area (Breit burg 2002, Gray et al. 2002).”

The drastic decline in species richness, Simpson's diversity, and CPUE documented here was consistent with work from other systems and suggests that from a multispecies, community perspective, there is a strong threshold avoidance response that begins when dissolved oxygen drops below approximately 4 mg l-1.

“The drastic decline in S, D, and CPUE documented here was consistent with work from other systems (e.g.Breitburg 2002, Eby & Crowder 2002, Keller et al. 2010) and suggests that from a multispecies, community perspective, there is a strong threshold avoidance response that begins when DO drops below ~4 mg l -1 .”