Thermal refugia reinforce macroalgal resilience against climate change in the southeastern Bay of Biscay.

Rising global temperatures present unprecedented challenges to marine ecosystems, demanding a profound understanding of their ecological dynamics for effective conservation strategies. Over a comprehensive macroalgal assessment spanning three decades, we investigated the spatiotemporal evolution of shallow-water benthic communities in the southern Bay of Biscay, uncovering climate-resilient areas amidst the ongoing phase shift in the region. Our investigation identified seven locations serving as potential climate refugia, where cold-affinity, canopy-forming macroalgal species persisted and community structure was similar to that observed in 1991.

Neighbourhood benthic configuration reveals hidden co-occurrence social diversity.

Ecological interactions among benthic communities are crucial for shaping marine ecosystems. Understanding these interactions is essential for predicting how ecosystems will respond to environmental changes, invasive species, and conservation management. However, determining the prevalence of species interactions at the community scale is challenging.

The thermal journey of macroalgae: Four decades of temperature-induced changes in the southeastern Bay of Biscay.

Global warming is triggering significant shifts in temperate macroalgal communities worldwide, favoring small, warm-affinity species over large canopy-forming, cold-affinity species. The Cantabrian Sea, a region acutely impacted by climate change, is also witnessing this shift. This study delved into the impacts of increasing sea surface temperature on the subtidal macroalgal communities in the southeastern Bay of Biscay over the last four decades, by using data from the years 1982, 2007, 2014, and 2020.

Short-term response of macroalgal communities to ocean warming in the Southern Bay of Biscay.

Climate change is causing significant shifts in biological communities worldwide, including the degradation of marine communities. Previous research has predicted that southern Bay of Biscay canopy-forming subtidal macroalgal communities will shift into turf-forming Mediterranean-like communities by the end of the century. These predictions were based on a community-environment relationship model that used macroalgal abundance data and IPCC environmental projections.

A spatially-modelled snapshot of future marine macroalgal assemblages in southern Europe: Towards a broader Mediterranean region?

The effect of climate change on species distribution has been the focus of much recent research, but the community-level approach remains poorly studied. Our investigation applies a present assemblage-environment relationship model for the first time to the predict changes in subtidal macroalgal assemblages in the northern Iberian Peninsula under the RCP 4.5 and RCP 8.