Mr Adrian Tsz Chun Wong1, Prof Gray A. Williams1
1The Swire Institute of Marine Science and the Area of Ecology & Biodiversity, The School of Biological Sciences, The University of Hong Kong, , PR China
How can species survive living in the splash zone of tropical rocky shores where food is sparse, immersion is rare and rock temperatures can exceed 60 °C? This is the challenge faced by the limpet, Lottia dorsuosa, which has to cope with extremely hot tropical summers and cool, temperate winters on rocky shores in Hong Kong. Paradoxically, this limpet is not thermally tolerant, as its tolerance limits are up to 15 °C below summer rock temperatures, but it manages to hang on in this harsh environment during the summer by hiding in dense aggregations in thermal refuges (crevices and overhangs) where temperatures remain within the limpet’s tolerance limits. During this time, the limpets appear to aestivate and do not move at all, minimizing their energy expenditure and relying on energy reserves stored during winter. As conditions ameliorate towards winter, the limpets leave these refuges and roam freely, feeding on ephemeral supplies of algae and biofilm, and building up their energy reserves for the next summer. Adopting a seasonal aestivation strategy, therefore, appears to be the key to success for this limpet to survive at the very edges of the intertidal zone in the monsoonal tropics. This strategy, however, comes with trade-offs, and the key follow-on question is whether just being able to hang on is good enough in a future warming world?
Biography:
Based in Hong Kong, Gray is the Director of the Swire Institute of Marine Science and Professor in the School of Biological Sciences, The University of Hong Kong and a Guest Professor at Xiamen University, China. His primary research interests focus on the ecophysiology and behaviour of intertidal species; especially those inhabiting the extreme high shore area in the tropical SE Asia region.
