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How Intertidal Gastropods Deal with Acidified Seawater
Amaral, V., Cabral, H.N. and Bishop, M.J. 2014. Prior exposure influences the behavioral avoidance by an intertidal gastropod, Bembicium aurantum, of acidified waters. Estuarine, Coastal and Shelf Science 136: 82-90.

The authors write that "the capacity of organisms to adapt to change may depend on their phenotypic plasticity," noting that "plasticity in life-history, physiology or behavior may enable populations to persist and maintain viable populations under a broad range of environmental conditions," citing the work of Charmantier et al. (2008) and Tuomainen and Candolin (2011).

What was done
Amaral et al. examined the role of behavioral avoidance of sub-optimal conditions in enabling the intertidal gastropod, Bembicium aurantum, to persist in mangrove forests affected by the low pH runoff from acid sulphate soils. This they did by exposing individuals they collected from acidified and reference sites to water obtained from both types of sites and then observing how they reacted.

What was learned
The three researchers report that" gastropods from acidified sites showed significantly higher activity in and more rapid migration out of acidified waters than out of reference waters," while "gastropods from reference locations showed a significantly weaker response to acidified water than those from acidified waters, and which did not significantly differ from their response to reference water."

What it means
Amaral et al. suggest that "both the migration of gastropods out of acidified waters and retraction into their shells serves to reduce exposure time to acidified waters and may reduce the impact of this stressor on their populations," while "the stronger response to acidification of gastropods from populations previously exposed to this stressor suggests that the response may be learned, inherited or induced over multiple exposures." And so they conclude that their study "adds to growing evidence that estuarine organisms may exhibit considerable physiological and behavior adaptive capacity to acidification."

Charmantier, A., McCleery, R.H., Cole, L.R., Perrins, C., Kruuk, L.E.B. and Sheldon, B.C. 2008. Adaptive phenotypic plasticity in response to climate change in a wild bird population. Science 320: 800-803.

Tuomainen, U. and Candolin, U. 2011. Behavioral responses to human-induced environmental change. Biological Reviews 86: 640-657.

Reviewed 21 May 2014