Desiccation facilitates wave-induced mortality of the intertidal alga Fucus gardneri

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 232:75-82 (2002) - doi:10.3354/meps232075 Desiccation facilitates wave-induced mortality of the intertidal alga Fucus gardneri R. Nicholas Haring1, Megan N. Dethier2,*, Susan L. Williams3 1Department of Biology, California State University, Northridge, Northridge, California 91330, USA 2Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington 98250, USA 3Bodega Marine Laboratory, University of California at Davis, Bodega Bay, California 94923-0247, USA *Corresponding author. E-mail: mdethier@u.washington.edu ABSTRACT: Physical factors such as desiccation and water motion can influence the abundance and performance of intertidal seaweeds. We addressed the hypothesis that the intertidal seaweed Fucus gardneri can be dislodged or damaged by relatively small waves if weakened by the effects of desiccation. Stress-strain curves generated for desiccated and hydrated thalli revealed that desiccated stipes were more brittle than hydrated stipes and required less total work (energy) to break. Results from a dynamic loading experiment suggest that the oscillating motion of the waves may be an important factor in breaking brittle stipes. Therefore, seemingly benign water motion may provide sufficient force to damage or dislodge desiccated thalli. In the late spring and summer in this area, waves are generally small but desiccating conditions are common as low tides fall during midday. Mortality of field populations is high during these seasons; thalli experimentally protected from desiccation suffered many fewer losses. However, desiccated F. gardneri can rehydrate rapidly (less than 1 min), minimizing the window of time that wave forces can break stipes. This study provides an example of how 2 sub-lethal physical factors, desiccation and benign waves, can interact to cause mortality in an upper intertidal seaweed. KEY WORDS: Desiccation · Biomechanics · Fucus gardneri · Wave forces · Population growth · Mortality Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 232. Online publication date: May 03, 2002 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2002 Inter-Research.