Journal
AMERICAN NATURALIST
Volume 179, Issue 3, Pages 363-374Publisher
UNIV CHICAGO PRESS
DOI: 10.1086/664080
Keywords
density-dependent predation; herbivory; interaction modification; slow-growth/high-mortality hypothesis; trait-related indirect effect; trophic cascade
Categories
Funding
- Wesleyan University
- Howard Hughes Medical Institute
- University of California-Irvine Academic Senate Council on Research, Computing, and Libraries
Ask authors/readers for more resources
Effects of plant traits on herbivore-carnivore interactions are well documented in component communities but are not well understood at the level of large, complex communities. We report on a 2-year field experiment testing mechanisms by which variation in food quality among eight temperate forest tree species alters avian suppression of an assemblage of dietary generalist caterpillars. Plant quality and bird effects varied dramatically among tree species; high-quality plants yielded herbivores of 50% greater mass than those on low-quality plants, and bird effects ranged from near 0% to 97% reductions in caterpillar density. We also find evidence for two mechanisms linking host plant quality to bird effects. If caterpillar density was statistically controlled for, birds had relatively strong effects on the herbivores of low-quality plants, as predicted by the slow-growth/high-mortality hypothesis. At the same time, caterpillar density increased with plant quality, and bird effects were density dependent. Consequently, the net effect of birds was strongest on the herbivores of high-quality plants, a dynamic we call the high-performance/high-mortality hypothesis. Host plant quality thus changes highly generalized herbivore-carnivore interactions by two complementary but opposing mechanisms. These results highlight the interrelatedness of plant-herbivore and herbivore-carnivore interactions and thus the importance of a tritrophic perspective.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available