Marine Invasive Species Dynamics

Marine invasive species emerge when organisms are transported by human activities beyond their native ranges and establish self‐sustaining populations in new regions. Shipping (ballast water, hull fouling), recreational boating and aquaculture represent principal vectors, creating stepping-stone habitats such as ports and marinas that elevate propagule pressure and facilitate long-distance dispersal. Once introduced, non-indigenous species (NIS) can alter trophic networks, outcompete native fauna, modify habitat structure and impose substantial economic costs on fisheries, aquaculture and coastal infrastructure. Environmental factors—including water temperature, salinity and pollution—modulate establishment success, while climate change and increasing coastal development are amplifying both the frequency of introductions and the potential for secondary spread. Effective management hinges on early detection through standardised monitoring, risk assessment guided by network models and targeted biosecurity measures to disrupt key pathways. Recent advances in molecular tools and ecological modelling are improving the resolution of invasion histories and enabling the identification of cryptic lineages. Integrated strategies that combine routine surveillance, rapid response protocols and stakeholder engagement are essential to curb the global impact of marine invasions and safeguard biodiversity, ecosystem services and coastal economies.

Research from Nature Portfolio

Advances in molecular phylogeography have unveiled cryptic invasion dynamics within fouling communities. Analyses of mitochondrial gene markers across multiple coastlines revealed that superficially identical populations of an invasive bryozoan actually comprise genetically distinct lineages with temperature-correlated distributions. This latitudinal segregation underlines the role of pre-existing thermal adaptations in shaping introduction patterns and highlights the necessity of molecular diagnostics to distinguish cryptic species. By resolving fine-scale genetic structure, these studies inform more precise risk assessments and illustrate how hidden diversity can influence invasion trajectories and management priorities.

Marine Invasive Species Dynamics publication trend

The graph below shows the total number of articles in marine invasive species dynamics across all publications each year (not limited to Nature Index journals).

Technical terms

Non-indigenous species (NIS): organisms introduced by human action outside their native range that establish and spread.

Propagule pressure: the frequency and quantity of organisms introduced to a new environment.

Hull fouling: the assemblage of organisms attached to submerged surfaces of vessels, serving as a vector.

Cryptic invasion: incursion by genetically distinct lineages not distinguishable by morphology alone.

Stepping-stone habitat: intermediate sites, such as marinas, that facilitate sequential colonisation along invasion pathways.

Network model: a mathematical representation of connections among nodes (e.g. ports) used to analyse spread dynamics.

References

1. Buoys are non-indigenous fouling hotspots in marinas regardless of their environmental status and pressure. The Science of The Total Environment (2023).
2. Recreational vessel networks reveal potential hot spots for marine pest introduction and spread. Journal of Applied Ecology (2024).
3. Monitoring Non-indigenous Species in Port Habitats: First Application of a Standardized North American Protocol in the Mediterranean Sea. Frontiers in Marine Science (2021).
4. Ecology of cryptic invasions: latitudinal segregation among Watersipora (Bryozoa) species. Scientific Reports (2012).
5. A Framework for Understanding Marine Cosmopolitanism in the Anthropocene. Frontiers in Marine Science (2018).