To document impacts of an extreme marine heat wave on the distribution and abundance of a forest-forming seaweed, and to assess potential long-term changes in reef communities
Type of Study:
Natural experiment (before-after comparison)
The marine heat wave eliminated Scytothalia dorycarpa at its warm distribution limit, causing a range contraction of approximately 100 km (approx. 5% of its global distribution). Seawater temperatures during the HW exceeded the seaweed’s physiological threshold and caused extirpation of marginal populations.
Surveys before an after the marine heat wave at different geographical locations
Southwestern Australia, Jurien Bay
Response variable :
Presence-absence and reef-scale percent cover of Scytothalia, percent cover of community components (benthic functional groups)
40 x 25m transects, 12 x 0.5m2 quadrats + variable sampling effort in historical surveys.
Smale D. A. & Wernberg T. (2013) Extreme climatic event drives range contraction of a habitat-forming species. Proceedings of the Royal Society B: Biological Sciences 280.