Patterns and drivers of high-latitude reef communities along the tropical-to-temperate transition

Dr Brigitte Sommer1,2, Dr Maria Beger3, Prof John M Pandolfi2,4

1School of Life and Environmental Sciences, The University of Sydney, Camperdown, Australia, 2School of Biological Sciences, The University of Queensland, St Lucia, Australia, 3University of Leeds, Leeds, United Kingdom, 4ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, Australia

Biogeographic transition zones, where tropical, subtropical and temperate species overlap, are being transformed by changes in species distributions and interactions and provide a unique ‘window’ into how climate change might influence complex biological systems. Here, we examine these dynamics in the tropical-to-temperate transition zone in eastern Australia, where corals occur at their high-latitude range limits and overlap with cold-water species such as kelp seaweeds. We combine fine scale field data for multiple taxa with species trait and environmental data to investigate the mechanisms that shape ecological dynamics in this region. For corals, results are consistent with the hierarchical filtering model of community assembly, whereby species pass through a regional climatic filter based on their tolerances for marginal conditions and subsequently segregate into local assemblages according to the relative strength of habitat filtering and species interactions. Moreover, patterns of algae, sea urchins and fish abundance point to the important role of these taxa on high-latitude reefs. For example, coral cover is negatively associated with algae cover, and sea urchins are more abundant at higher latitudes, where they likely release corals from competition with macroalgae. Understanding the links between community composition, species interactions and environmental conditions for multiple taxa leads to an ecosystem understanding of biogeographic transition zones and of how complex marine ecosystems may respond to climate change.


Brigitte Sommer is a Postdoctoral Research Fellow at The University of Sydney. Her research combines field ecology and statistical modelling to understand the processes that control the distribution and abundance of marine organisms and how they will be affected by climate change. She has a particular interest in ecosystems at the transition of biogeographical zones, where tropical and temperate species overlap at the limits of their geographical distributions and environmental tolerances.

Species on the Move

An International Conference Series

The conference brings together scientists and natural resource managers working in the disciplines of global change, biogeography and evolution, and relevant in contexts of natural resource management, biodiversity management and conservation, and theoretical ecology.

Species responses to climate change is a rapidly evolving research field, however, much of our progress is being made in independent research areas: e.g. understanding the process vs responding to the implications, terrestrial vs marine ecosystems, global meta-analyses vs in depth species-specific approaches. This interdisciplinary conference develops connections between these parallel streams, and across temporal and spatial scales.

Conference Managers

Please contact the team at Conference Design with any questions regarding the conference.

© 2015 - 2019 Conference Design Pty Ltd