ECORISC · Understanding resilience of seed dispersal in insular systems to climate change

Understanding resilience of seed dispersal in insular systems to climate change

The ECORISC project addresses a pressing global issue: the impact of climate change and other synergistic drivers on seed dispersal, which is a crucial ecosystem process for maintaining biodiversity and ecosystem functioning. Seed dispersal networks involve complex interactions between plants and their seed dispersers, such as birds and other animals, which play a pivotal role in maintaining healthy ecosystems by facilitating plant reproduction and diversity. As climate change accelerates, its effects on ecological systems become increasingly severe. Rising temperatures, changing precipitation patterns, and other climate-induced alterations are reshaping habitats and species distributions. This is especially critical on islands, which, despite comprising only 5.3% of global land area, harbor around 30% of biodiversity hotspots and many threatened species. Islands’ ecosystems are highly sensitive to invasive species and environmental changes, making them more vulnerable to the compounded impacts of climate change. Understanding how seed-dispersal networks on islands respond to these threats is essential for predicting ecological outcomes and informing conservation strategies. The ECORISC project aims to provide a comprehensive analysis of how climate change affects seed-dispersal networks. The project is structured around three main objectives: (1) The first objective was to revisit a global dataset of seed-dispersal networks, encompassing interactions between plants and their dispersers across various ecosystems and islands. This dataset includes approximately 225 networks, with detailed information on plant and disperser species and their main functional traits. By analyzing the plant and frugivore assemblages of those networks, we gain insights into their structure and patterns, which are critical for understanding how different networks might respond to climate change or invasive species. (2) The second objective focuses on evaluating the vulnerability of plants to climate change by examining the redundancy and complementarity of their dispersers' climatic niches. This further involves involves estimating how shifts in climate might affect plant-disperser interactions and whether ecosystems are more likely to collapse from the bottom up (i.e. plant's are lost first), top down (i.e. dispersers are lost first), or all at once, as climate change continues. (3) The third objective investigates how climate change affects the structure and function of seed-dispersal networks. This includes assessing potential structural changes, such as shifts in network modularity, and functional consequences, like declines in long-distance seed dispersal. By using simulation models and real-world data, we explore how climate-induced extinctions and changes in species traits influence seed dispersal functions. The results of the ECORISC project are expected to contribute to the broader field of ecological research and conservation. By developing a novel framework for assessing both species vulnerability and ecosystem functions, the project will provide valuable insights into how global change impacts seed-dispersal networks and their associated ecological functions. This understanding will be crucial for informing conservation strategies and policy-making, particularly in identifying which species and ecosystems are most at risk and developing targeted interventions to mitigate these risks. Through this project, we aim to advance scientific knowledge, influence conservation practices, and contribute to global efforts to address climate change impacts on ecological systems.

Data: CORDIS, © European Union