Ecological Dynamics of Hypoxia-Impacted Coastal Fishes

Hypoxia, defined as low dissolved oxygen levels (≤2 mg L⁻¹), is increasingly prevalent in coastal zones due to nutrient enrichment and water-column stratification. This stressor alters fish physiology—reducing aerobic scope, growth and reproductive capacity—and drives behavioural responses such as avoidance and aggregation in oxygenated refuges. Habitat compression into narrow oxygenated corridors intensifies competition, predation pressure and disease transmission, reshaping community composition and trophic interactions. Species differ in tolerance thresholds, leading to shifts in biodiversity and functional roles that cascade through food webs. Spatial and temporal variability of hypoxic events, linked to eutrophication, upwelling and climate variability, governs the scale and persistence of impacts. Integrated field studies and models reveal that recurrent hypoxia can induce regime shifts in assemblages, alter recruitment success and challenge assumptions in stock assessments. Globally, expanding hypoxic zones undermine fisheries sustainability and coastal ecosystem services, demanding adaptive management strategies that account for oxygen dynamics.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Ecological Dynamics of Hypoxia-Impacted Coastal Fishes publication trend

The graph below shows the total number of articles in ecological dynamics of hypoxia-impacted coastal fishes across all publications each year (not limited to Nature Index journals).

Technical terms

Hypoxia: A condition in aquatic ecosystems where dissolved oxygen falls below levels necessary to sustain most aerobic life, typically ≤2 mg L⁻¹.

Deoxygenation: The long-term reduction in oxygen concentration in marine and coastal waters driven by warming, stratification and nutrient loading.

Habitat compression: The confinement of mobile organisms to smaller, oxygenated areas during hypoxic events, leading to increased local densities and altered interactions.

Trophic ecology: The study of feeding relationships, energy transfer and nutrient cycling among organisms within an ecosystem.

References

1. A Selected Review of Impacts of Ocean Deoxygenation on Fish and Fisheries. Fishes (2023).
2. Moving on up: Vertical distribution shifts in rocky reef fish species during climate‐driven decline in dissolved oxygen from 1995 to 2009. Global Change Biology (2021).
3. The Legacy of Hypoxia: Tracking Carryover Effects of Low Oxygen Exposure in a Demersal Fish Using Geochemical Tracers. Transactions of the American Fisheries Society (2019).