Dr Scott Bennett1, Prof Neville Barrett, Dr Sahira Bell, Dr Nestor Bosch, Prof. Sean Connell, Prof. Graham Edgar, Prof. Craig Johnson, Associate Prof. Scott Ling, Dr Ezequiel Marzinelli, Erin McCosker, Dr Albert Pessarrodona, Prof. Alistair Poore, Paula Sgarlatta, Dr Shannen Smith, Prof. Peter Steinberg, Associate Prof. Rick Stuart-Smith, Prof. Adriana Vergés, Prof. Thomas Wernberg, Dr Salvador Zarco-Perello
1Institute of Marine and Antarctic Studies, University of Tasmania, Taroona, Australia
Poleward extension of warm-affiliated species under climate change is drawing increased attention to the impacts of herbivores on temperate reefs. The generality of these impacts and vulnerability of temperate reef systems to overgrazing, however, remains unclear due to a low recognition of the environmental context within which changes are taking place. Here we review the taxonomic and functional diversity of herbivores and biogeographical differences in herbivore impacts on temperate reefs across Australia. We identified 100 studies that directly measured herbivory on temperate rocky reefs in Australia, representing a total of 1076 seaweed-herbivore interactions between 84 species of herbivore and 112 species of seaweed. Herbivory fell into six main functional roles among which 45 species from 5/6 classes of herbivore were recorded removing seaweed canopies and 22 species were recorded removing turfs. Individual species also performed multiple functions on reefs highlighting the plasticity in species behaviour under different environmental contexts. Despite a relatively high diversity of herbivores, only two species have been documented to cause overgrazing of kelp forests at a reef-scape scale. Impacts of herbivory on temperate reefs are increasing in multiple regions, driven by increased densities of a small number of species that differ between regions. These changes mask broad declines in native herbivore diversity across temperate Australia.
Presentation Slides – Scott Bennett
Biography:
I am marine ecologist with a research focus on temperate reefs and climate change ecology. My research approach is multidisciplinary, with a core focus on comparative ecology across broad spatial and environmental gradients.
