Climate change could amplify weak synchrony in large marine ecosystems.

Area of Science:

• Marine Ecology
• Climate Change Biology
• Population Dynamics

Background:

• Climate change intensifies extreme environmental events and reduces environmental gradients.
• Metapopulation synchrony, or lack thereof, influences population stability and rescue effects.
• Understanding factors limiting synchrony is crucial for predicting ecosystem responses to global change.

Purpose of the Study:

• To quantify the roles of spatial heterogeneity in density dependence, environmental responses, and environmental gradients in inhibiting metapopulation synchrony.
• To assess the impact of these factors on marine fish and invertebrate populations across different ecosystems.
• To predict how future climate change scenarios might affect population synchrony and stability.

Main Methods:

• Utilized long-term ecological data for 36 marine species.
• Employed empirical dynamic models to analyze population dynamics.
• Quantified spatial heterogeneity in density dependence and environmental responses.
• Assessed the influence of environmental gradients and nonlinear response curves.

Main Results:

• Spatial heterogeneity in population dynamics was as significant as environmental drivers in explaining population variation.
• Weak population synchrony was observed in the California Current Ecosystem due to diverse species responses.
• Environmental gradients and nonlinear responses limited synchrony in the Northeast U.S. Shelf Ecosystem.

Conclusions:

• Spatial heterogeneity and diverse species responses are critical for maintaining marine ecosystem resilience.
• Weakening environmental gradients could increase population synchrony and large-scale declines, particularly in commercially important species.
• The study provides a framework for quantifying landscape-scale resilience and identifying climate change impacts on species stability.