Lessons on effectiveness and long-term prevention from broad-scale control of invasive alien species in Scotland’s rivers and lochs

Prior to 2008 there were few invasive alien species (IAS) initiatives operating in Scotland on a scale required for e?ective control. The establishment of the Biosecurity and Invasive Non-Native Species Programme by the Rivers and Fisheries Trusts of Scotland was the ?rst attempt to link local e?orts with national IAS strategy on scales appropriate to the e?ective control of target species. The programme worked with 26 local ?sheries trusts to produce biosecurity plans that covered over 90% of Scotland’s rivers and lochs. The programme implemented a range of prevention measures, including promoting awareness of invasive species issues and the need for biosecurity among water users. Projects were established for invasive plants on most major river systems, and for American mink (Neovison vison) in the north of Scotland. These projects involved public/private partnerships, using a mix of professional sta? and volunteers. Interactive data management systems were developed to manage input from a large number of individuals and to inform an adaptive management approach. These control projects demonstrated that it is feasible to reduce the size and density of target populations of invasive species across large geographic areas. The key to maintaining the momentum of this control e?ort in the future will be to demonstrate sustainable IAS management in the longer term. This challenge led to the formulation of the Scottish Invasive Species Initiative (SISI) whose overall aim is the development of a long-term, cost-e?ective strategy for IAS management throughout the north of Scotland. SISI will test strategies derived from experience and information from previous control projects. Important areas that the initiative will seek to address include de?ning outcomes, integrating IAS management into other management initiatives, and maintaining partnership interest and cohesiveness in a challenging funding environment.