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<DIV><FONT face=Arial size=2>Ecology Letters<BR>Volume 13 Issue 2, Pages 194 -
201<BR>Published Online: 29 Dec 2009<BR></FONT></DIV>
<DIV><FONT face=Arial size=2><FONT size=4>Prey diversity is associated with
weaker consumer effects in a meta-analysis of benthic marine
experiments</FONT><BR>Kyle F. Edwards*, Kristin M. Aquilino, Rebecca J. Best,
Kirsten L. Sellheim and John J. Stachowicz <BR>Center for Population Biology,
University of California Davis, One Shields Avenue, Davis, CA 95616,
USA<BR>Correspondence to *E-mail: <A
href="mailto:kedwards@ucdavis.edu">kedwards@ucdavis.edu</A> <BR></FONT></DIV>
<DIV><FONT face=Arial size=2><STRONG>ABSTRACT</STRONG><BR>A rapidly accumulating
body of research has shown that species diversity consistently affects the
functioning of ecosystems. The incorporation of trophic complexity and the
extension of this research to larger scales and natural ranges in species
diversity remain as important challenges for understanding the true magnitude of
these effects in natural systems. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Here, we test whether the diversity of prey
communities affects the magnitude of aggregate consumer effects.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>We conducted a meta-analysis of 57 consumer removal
field experiments from a range of intertidal and subtidal hard substrate marine
communities. <U>We found that the richness of the prey community was the
strongest predictor of the magnitude of consumer effects </U>while controlling
for habitat type, taxonomic composition, and other variables. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Consumer removal increased aggregate prey abundance
on average by 1200% at the lower limit of prey diversity (two species), but only
200% at the upper limit of 37 species. Importantly, compositional change was
substantial at both high and low prey diversity, suggesting predation intensity
did not vary with prey richness. Rather diverse prey communities appear to be
more capable of maintaining abundance via compensatory responses, by containing
prey species that are resistant to (or tolerant of) predators. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>These results suggest that the effects of species
diversity on trophic interactions may scale consistently from small-scale
manipulations to cross-community comparisons.</FONT></DIV></BODY></HTML>