Speaker: Rodrigo Tardin, Professor, Federal University of Rio de Janeiro, Brazil

Topic: How climate change impacts a coastal tropical dolphin? 

Climate change impacts coastal and marine ecosystems through warming, acidification, and deoxygenation. These effects are expected to intensify without substantial mitigation efforts. In tropical regions, rising ocean temperatures may push marine species, such as coastal cetaceans, to their thermal limits, leading to species redistributions and cascading effects on community and ecosystem dynamics. In this talk, I will share the results of the most comprehensive datasets of occurrences for Guiana dolphins from systematic boat-based surveys conducted between 1987 and 2023, across seven countries.  Guiana dolphins face unprecedented challenges from ongoing multiple and cumulative human activities, which are likely to be exacerbated by climate change over the next four decades. We built ensemble Species Distribution Models (SDM) to predict future distributions under the latest CMIP6 projected scenarios: optimistic  (SSP1-2.6), intermediate (SSP2-4.5), and pessimistic (SSP5-8.5).  Expert knowledge was used to validate model predictions. We ask here i) how different climate change scenarios will affect Guiana dolphin distribution? and ii) how the current Marine Protected Area (MPA) network may protect dolphins in the present and future? Our study contributes to ongoing efforts to understand the potential effects of projected climate change scenarios on coastal tropical marine predators.