Abstract: | The influence of desiccation on the mechanical properties of the intertidal macroalga Iridaea cordata (Turner) Bory (Rhodophyta) was investigated over a range of water losses (0–83%) that bracketed in situ levels (26–67%). The tissue modulus (stiffness) remained constant for water losses up to about 70%, but increased sharply with losses between 70–83%. Tissue strength of desiccated samples did not fall below the range measured for undesiccated samples. There was a significant increase in breaking strain up to water losses of about 50%, after which breaking strain decreased. The relationship between toughness and desiccation resembled that for breaking strain. Overall, the mechanical properties of Iridaea cordata did not deteriorate when desiccated to levels consistent with those observed in the field. |