Variance in ecological consumer–resource interactions
- 21 September 2000
- journal article
- letter
- Published by Springer Science and Business Media LLC in Nature
- Vol. 407 (6802), 370-374
- https://doi.org/10.1038/35030089
Abstract
Food-web models use the effect size of trophic interactions to predict consumer–resource dynamics1,2,3. These models anticipate that strong effects of consumers increase spatial and temporal variability in abundance of species, whereas weak effects dampen fluctuations4,5,6. Empirical evidence indicates that opposite patterns may occur in natural assemblages7. Here I show that spatial variance in the distribution of resource populations is sensitive to changes in the variance of the trophic interaction, in addition to the mean effect of consumers, relative to other causes of spatial variability. Simulations indicate that both strong and weak direct effects of consumers can promote spatial variability in abundance of resources, but only trophic interactions with a large mean effect size can reduce variation. Predictions of the model agree with the results of repeated field experiments and are consistent with data from published consumer–resource interactions, proving to be robust across widely varying environmental conditions and species’ life histories. Thus, food-web models that embody variance in trophic interactions may have increased capacity to explain the wide range of effects of consumers documented in empirical studies.Keywords
This publication has 26 references indexed in Scilit:
- PREDICTING DIRECT AND INDIRECT INTERACTIONS DURING SUCCESSION IN A MID-LITTORAL ROCKY SHORE ASSEMBLAGEEcological Monographs, 2000
- Variable Predation: Effects of Whelks on a Mid‐Intertidal Successional CommunityEcological Monographs, 1996
- Food Web Complexity and Community DynamicsThe American Naturalist, 1996
- Size‐Dependent Competition: Effects on the Dynamics Vs. The End Point of Mussel Bed SuccessionEcology, 1993
- Non-Additive Impact of Blue Crabs and Spot on Their Prey AssemblagesEcology, 1989
- Comparing Fish and Urchin Grazing in Shallow and Deeper Coral Reef Algal CommunitiesEcology, 1988
- Predation Can Increase Variability in the Abundance of Prey on SeashoresOikos, 1988
- Three-Way Interactions: Barnacles, Limpets, and Algae in a Sonoran Desert Rocky Intertidal ZoneThe American Naturalist, 1986
- Intertidal Mosaics: Patch Size, Propagule Availability, and Spatially Variable Patterns of SuccessionEcology, 1984
- Food Webs: Linkage, Interaction Strength and Community InfrastructureJournal of Animal Ecology, 1980