current and 25V were applied to the hot plate system throughout the deployment. Therefore, the hot plate system required a maximum power input of 500 watts. Data on the behaviour of the thermal gradient over the hot plate under different flow conditions were collected from a large experimental flume facility. Unidirectional flow rates were selected to represent typical current speeds observed in the Swan River during tidal cycles: low flow (,0.01 ms21), medium flow (,0.05 ms21) and high flow (,0.12 ms21). Flow was measured with an Acoustic Doppler Velocimeter (ADV); water velocity 4 mm above the hot plate surface was recorded every second for ten minutes (prior to taking temperature readings). Under each flow condition, the temperature of the boundary layer across the hot plate was recorded using high precision T-type temperature probes mounted above the centre of the plate, perpendicular to flow direction. 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Poloczanska E, Babcock RC, Butler A, Hobday AJ, Hoegh-Guldberg O, et al. (2007) Climate change and Australian marine life. Oceanograph Mar Biol Ann Rev 45: 407–478. PLoS ONE | www.plosone.org 4 January 2011 | Volume 6 | Issue 1 | e16050