Spread of invasive species into Scotland: study

Key conclusions

There are many INNS spanning a range of species groups and environments that have the potential to arrive, establish and impact biodiversity and ecosystem services, human health and economies in Scotland.

A high proportion of the INNS (species groups including plants, animals and microorganisms) are predicted to arrive through the movement of plants through horticultural trade routes including within soil. There are opportunities to address unintentional introductions through the horticultural trade through biosecurity approaches.

In some cases, it may be appropriate to aggregate taxonomically similar INNS for the purposes of planning management actions or communication campaigns, for example flatworms.

Horizon scanning can underpin prioritisation of actions to prevent the arrival and establishment of INNS in Scotland. It is important to regularly review horizon scanning lists and repeat the approach every five years which is considered to be the approximate lag in flow of information across all non-native species.

Raising awareness and communication are important in preventing the introduction and spread of INNS. The Top 10 list agreed in consultation with NatureScot experts could be used within resources for diverse stakeholder groups spanning sectors.

Baseline information is critical to inform horizon scanning and databases on non-native species underpin such approaches. It is important to ensure rapid flow of information on non-native species to open access databases. There can be delays in detecting and reporting non-native species and additionally establishment status can be difficult to attribute for some non-native species. Adopting standard approaches and harmonising terminology, for example with respect to establishment status, should be prioritised and particularly noting the relevance to the Kunming-Montreal Global Biodiversity Framework Target 6 to "reduce rates of introduction and establishment of invasive alien species by 50 per cent”.