There is a growing understanding of the way in which certain species support ecosystem functionality, or provide ecosystem services that deliver nature-based solutions to human challenges such as flooding, pollution or food security. In particular, migratory species play a key role within the ecosystems they utilise due to their temporal presence and ability to connect different ecosystems, often thousands of miles apart. In Part 3 of this review, we carried out a rapid literature review to identify the various ecosystem services migratory species can provide. In particular, we looked at the potential role of these services as nature-based solutions to climate change, as well as the wider benefits they can bring

for people and ecosystems, to help decision makers begin to consider these issues in a cross- cutting and holistic way. This builds on the strategies identified in Part 2 for conserving migratory

species threatened with climate change, through investigating whether migratory species conservation can provide wider mitigation and adaptation benefits for biodiversity and people. Our review suggests that migratory species are particularly important for providing services related to the regulation and maintenance of ecosystems. Migratory bird, bat and insect species were found to be particularly key to pollination, seed dispersal and pest control, whilst large terrestrial and marine mammals, as well as sharks, were important for aiding carbon capture and providing other regulation and maintenance services. Other services related to culture (tourism, recreational activities, symbolic value and natural heritage) and provision (predominantly food) were also identified, though to a lesser extent. The results of the review suggest that conserving migratory species has the potential to improve ecosystem resilience, helping to mitigate the impacts of climate change and promote adaptation to increasingly frequent climatic hazards. Therefore, migratory species should be seen not only as ‘victims’ of the climate crisis, but also as a key part of a potential ‘solution’ to tackling the global impacts of climate change.