Future Climate Change Favours the Increase in Abundance of Smaller, Shorter‐lived Fish in the Northeastern Mediterranean

Abstract As species distributions shift due to climate change, functional alterations may also occur within marine communities, potentially leading to ecosystem‐wide transformations. With Mediterranean marine ecosystems projected to undergo tropicalization, it is crucial to understand how climate change will impact not only species distributions but also the functional traits of marine organisms. This study evaluated the potential effects of climate change on functional patterns in shallow reef fish communities in the northeastern Mediterranean. Using random forest models, we projected current and future abundances of the most common reef fish and estimated community‐weighted mean traits under mid‐ and long‐term climate scenarios. Our findings indicate a shift toward fish communities dominated by species with shorter lifespans, smaller maximum sizes and earlier maturity, along with increased growth rates and fecundity. Long‐term scenarios suggest functional homogenization, with reduced trait diversity due to environmental filtering, potentially leading to communities with higher functional redundancy. This study provides initial insights into how climate‐driven changes could reshape functional patterns in northeastern Mediterranean reef fish communities, with significant implications for ecosystem services and resilience. Read the free Plain Language Summary for this article on the Journal blog.