Trophic interactions will expand geographically but be less intense as oceans warm

Area of Science:

• Marine ecology
• Climate change impacts
• Trophic interactions

Background:

• Species interactions are shifting due to climate change-driven range shifts and physiological responses to warming.
• Marine ectotherms are particularly vulnerable as they often operate near their thermal limits, with limited refugia.
• Varying thermal limits across species and trophic levels exacerbate the impact of ocean warming on marine food webs.

Purpose of the Study:

• To assess the impact of temperature on reef fish trophic interactions in the Western Atlantic.
• To model projected changes in fish occurrence, biomass, and feeding intensity across latitudes under climate change scenarios.

Main Methods:

• Analysis of temperature effects on reef fish trophic interactions.
• Modeling of future fish distribution, biomass, and feeding intensity under ocean warming.

Main Results:

• Tropical reefs face diminished trophic interactions (herbivory, invertivory), potentially increasing algal dominance.
• Tropicalization events predicted, with herbivore feeding expanding from the Caribbean to extratropical reefs.
• Invertivore feeding declines globally, threatening a crucial trophic link; omnivore feeding decreases in some regions and increases in others.

Conclusions:

• Significant changes in reef fish trophic interactions are projected by 2050 due to ocean warming.
• These alterations can profoundly affect ecosystem functioning, leading to shifts in dominance and the emergence of novel ecosystems.
• Conservation strategies must consider these predicted changes to maintain marine ecosystem health and stability.