Revista Chilena de Historia Natural 78 (4): 603-614, 2005
RESEARCH ARTICLE
Laboratory experiments examining inducible defense show variable
responses of temperate brown and red macroalgae
Macroalgae can defend themselves against generalist and specialist
herbivores via morphological and/or chemical traits. Herein we examined the defensive responses (via relative palatability) of two
brown (Lessonia nigrescens, Glossophora kunthii) and two red algae (Grateloupia doryphora,
Chondracanthus chamissoi) from the northern-central coast of Chile against selected generalist meso-
herbivores. Two laboratory experiments were conducted to investigate whether (i) algae can respond generally to grazing pressure of
meso-herbivores (amphipods, isopods and juvenile sea urchins) and whether (ii) these algal responses were inducible. In order to
examine palatability and thus effectiveness of responses, feeding assays were run after each experiment using fresh algal pieces and
artificial agar-based food. Lessonia nigrescens responded to amphipods but not to sea urchins, and G. kunthii
showed inducible response against one species of amphipods. Grateloupia doryphora did not respond against any
of the tested grazers, whereas C. chamissoi responded against one species of amphipods and the tested isopod. Our
results indicate variable responses of macroalgae against selected generalist meso-herbivores and evidence of an inducible defense in
the brown alga G. kunthii.
Key words:
palatability,
defense, meso-herbivores, macroalgae
