Spotting intruders: Species distribution models for managing invasive intertidal macroalgae

Area of Science:

• Marine Ecology
• Invasive Species Biology
• Conservation Science

Background:

• Invasive macroalgae pose significant threats to marine biodiversity and ecosystem services globally.
• The Iberian Peninsula is experiencing establishment of several invasive macroalgal species, complicating management due to limited distribution data.
• Understanding the factors driving these invasions is crucial for developing effective control and prevention strategies.

Purpose of the Study:

• To map the probability of presence for six key invasive macroalgae species along the north-western Iberian Peninsula coast.
• To identify environmental and anthropogenic factors influencing the distribution of these invasive macroalgae.
• To provide data-driven recommendations for management and early detection strategies.

Main Methods:

• Conducted an extensive field survey along the north-western Iberian Peninsula coast.
• Utilized Species Distribution Models (SDMs) incorporating environmental and anthropogenic variables.
• Analyzed the relative importance of predictor variables in ensemble models.

Main Results:

• Southern Galician rias identified as primary hotspots for invasive macroalgae, with high occurrence probability for most studied species.
• Invasive macroalgae presence probability was generally low along the Portuguese coast.
• Physico-chemical variables were key predictors (57.27–85.24%), but anthropogenic factors significantly improved distribution models.

Conclusions:

• Management efforts should prioritize strengthening port surveillance and control in southern Galician rias.
• Early detection strategies are recommended for the Portuguese coast to mitigate potential future invasions.
• Integrating anthropogenic factors into SDMs is vital for accurate invasive macroalgae risk assessment and management.