Dr Micheli Duarte de Paula Costa1, Professor Kerrie A. Wilson1, Mr Philip J. Dyer1, Professor José Henrique Muelbert2, Professor Anthony J. Richardson1,3
1The University of Queensland, Brisbane, Australia, 2Universidade Federal do Rio Grande, Rio Grande, Brazil, 3CSIRO, Brisbane, Australia
Ocean warming is expected to displace species towards high latitudes. The Southwestern Atlantic Ocean is among the six richest marine biodiversity regions in the Southern Hemisphere, but also within the fastest warming hotspots in the ocean. Climate change will modify ocean circulation in the region, and consequently exacerbate species distribution patterns. Here, we investigated the climate-induced changes in the distribution of fish larvae and harvested species in the Southwestern Atlantic Ocean through a community-based modelling approach (Gradient Forest). The Gradient Forest approach uses information on all species simultaneously, rather than treating each species independently. We used two climate change scenarios (RCP 4.5 and 8.5) to answer our two main questions: could climate change affect the distribution, abundance and composition of fish larvae, and will communities of harvested species follow the same trends? We found that coastal and offshore groups of fish larvae and harvested species are likely to be displaced southwards. Greater changes in community composition are projected in the southern portion of the study area for both fish larvae and harvested species communities. As expected, greater changes were predicted under RCP 8.5, however, substantial changes in distribution patterns are expected even under the RCP 4.5 with potential implications for fisheries. There are few studies investigating the impact of climate change on fish larvae and their adults, and this is the first study predicting climate change influences focused on biological communities in the Southwestern Atlantic Ocean.
Micheli Costa is a marine biologist, with an interest in the impact of environmental and climatic variability on aquatic ecosystems and conservation. Her research includes biological oceanography, climate change ecology, and conservation planning and prioritization. She is currently a Postdoctoral Research Fellow at The University of Queensland (Australia) working on the Reef Restoration and Adaptation Program.