Optimising the long term management of invasive species affecting biodiversity and the rural economy using adaptive management

A large number of highly damaging invasive non-native species (INNS) have become established in South America. They affect native species, ecosystems and livelihoods. Many INNS are now so widespread that eradication is not an option. Their spread must be contained and their density reduced, in the long-term, in those areas where taking no action is not acceptable. This must be done as cost effectively as possible, and consider:

By how much should INNS density be reduced? This depends on the resources available for management and on the relationship between the abundance of the focal INNS and the harm it causes to people and biodiversity. Considering what harm would be caused in the future if no action was taken now is also important.

How should the desired reduction be achieved? Different individuals in a population contribute differently to spread. Thus, targeting the right age classes or acting in different seasons should be informed by the biology of the species (e.g. large pines produce more seeds than small ones).

Where should the species be reduced? The areas invaded by INNS are often vast and spatial prioritisation is necessary. INNS are not equally damaging in all areas. Some ecosystems and human activities can withstand low density INNS presence, while others are so vulnerable they cannot tolerate even low INNS density. An example is the critically endangered hooded grebe in Austral Patagonia, driven to near extinction by the introduced American mink. The cost of managing INNS also varies spatially, especially in South America, where some areas are very difficult to access and the workforce is sparse. A further important consideration is that INNS are mobile. They have been able to spread when they first invaded, and can re-invade areas from which they have been removed through dispersal. This is both a challenge and an opportunity if management can exploit known patterns of spread. Ecologists have been studying dispersal dynamics in detail for decades, but have rarely used this knowledge to design effective management interventions. For instance, it may be possible to deplete a mobile INNS by intensively removing it from a small, highly attractive area, hence cost-effectively "vacuuming" a much larger area, or the spread of a plant INNS may be contained by making the establishment of seeds unlikely through spatially targeted land management.

We will design and introduce to stakeholders a user-friendly decision tool that we expect will become widely used in Latin America. To make sure our approach is relevant for different contexts in Latin America, we will work with example species that have large impacts, and for which data already exist (invasive pines, privet, and mink). We will also model plausible scenarios for data-poor pine species, exotic grasses and carnivorous wasps, which impact local communities in Brazil, Argentina and Chile. We will find the most effective strategic management using sophisticated computer simulations considering species ecology, dispersal and intervention costs in a spatial context. We will identify where new data would most effectively reduce uncertainty on the best course of action. The problem we tackle is complex, and we will embed it in a process of co-operative adaptive management, so that managers continually improve their effectiveness by confronting different models to data. We will also use our project as a way to build research capacity in Latin America, by training early career researchers and PhD students by means of research visits, continuous collaboration and workshops.

Our project will have a tangible positive and immediate impact on people and biodiversity in Latin America by delivering a step-change in the management of problematic INNS.

In line with the call, this project is designed to have high immediate impact on livelihoods, sustainable economic development and biodiversity by explicitly considering spatial relationships in costs and benefits of management and between density and impacts of invasive non-native species (INNS). Our Adaptive Management approach and generic decision tool will support strategic and operational decisions on plant or animal INNS based on the best available evidence. Through an increase human capacity, we will leave a long-term legacy for continual improvement of best practice within the LATAM partner countries.

Beneficiaries include those concerned with meeting the UN's Sustainable Development Goals, distributed globally: conservation practitioners, government agencies, private companies and organizations seeking to control INNS to protect livelihoods and biodiversity worldwide will benefit. In the focal LATAM countries, Governments and agencies implementing policies will benefit through their published objectives to manage INNS, especially mink and wasps, e.g. Argentina's plan to grow eco-tourism and the Chilean Forest Service, now dealing with INNS within their Protected Wildlife Areas. Our project will help them to achieve CBD Aichi goals and other international commitments by enhancing their interdisciplinary capacity to address issues of INNS.

Local beneficiaries include the National and Provincial Parks in Patagonia and Brazil that need to deal immediately with our exemplar INNS, eco-tourism operators whose income relies on visitors to protected areas, and local communities whose livelihoods are severely impacted by mink predation on poultry, wasps reducing tourism and pastures degraded by invasive pines. Forestry companies relying on exotic tree plantations will also benefit from the decision tool in meeting their obligations under the ISO 14001 Environmental Management System or the Forest Stewardship Council (FSC) to control the spread of exotic trees in the wider landscape. Failure to do so will risk achieving certification and its economic benefits.

All the above will benefit from more strategic, optimised, effective management of INNS through a new process for the evaluation of what may be sustainably achieved given ecological, cost and access constraints associated with the long-term management of INNS that cannot be eradicated. This will lead to a reduction of economic and logistic efforts with unattainable goals, and progress towards sustainable goals, which can be critical considering the many demands on funding in LATAM for conservation and INNS control.

We plan to hold dissemination workshops with practitioners, policy makers and researchers to include discussions of lessons learned and hands-on practice with evaluating management scenarios with our decision tool. The first, hosted in Los Rios, Chile, will launch the project nationally and mobilise decision makers and local communities around the INNS crisis, emphasising the value of adaptive management and the participatory approach. Three further workshops in Chile, Argentina and São Paulo State, Brazil will focus on managing tree invasions. They will involve national certification agencies, forestry companies, protected area staff and managers of FSC plans, and aim to ensure all players have the same information and to promote our decision tool as the basis for INNS management in extensive forestry. The final workshop in Buenos Aires will cover progress in designing strategic mink control for conservation, and include participants from Chile and Argentina. Optimised management plans for study sites will be demonstrated.

We will also make extensive use of the contacts networks and positions of trust with decision makers and local area managers of our LATAM partners, and of press releases, social media, local presentations, nationally focussed web-pages, printed control guides and an online manual for foresters in Spanish and Portuguese.