The role of environmental conditions in regulating long-term dynamics of an invasive seaweed

Abstract The mechanisms underpinning long-term dynamics and viability of invader populations in the receiving environment remain largely unknown. We tested hypothesis that temporal variations abundance a well-established invasive seaweed, Caulerpa cylindracea , NW Mediterranean, could be regulated by inter-annual fluctuations environmental conditions. Abundance data C. sampled repeatedly between 2005 2020 at peak its growing season (late summer/early fall), were related to interannual seasonal seawater temperature, wind speed rainfall recorded during different growth phases alga, both subtidal intertidal habitats. In habitats, higher cover was associated with lower temperature spring summer, when seaweed exits winter resting phase starts period active growth. addition, positively autumn intensity daily total precipitation. Our study reveals importance variation abiotic factors shaping patterns Identifying population is essential predict time conditions under which an can thrive, thus guide management strategies aimed containing invasions current future climates.