Effects of predatory ants on lower trophic levels across a gradient of coffee management complexity
Article first published online: 1 FEB 2008
© 2008 The Authors
Journal of Animal Ecology
Volume 77, Issue 3, pages 505–511, May 2008
How to Cite
Philpott, S. M., Perfecto, I. and Vandermeer, J. (2008), Effects of predatory ants on lower trophic levels across a gradient of coffee management complexity. Journal of Animal Ecology, 77: 505–511. doi: 10.1111/j.1365-2656.2008.01358.x
- Issue published online: 27 FEB 2008
- Article first published online: 1 FEB 2008
- Received 2 July 2007; accepted 13 November 2007 Handling Editor: Guy Woodward
- Chiapas Mexico;
- coffee agroecosystems;
- dominant arboreal ants;
- food web structure;
- intraguild predation
- 1Ants are important predators in agricultural systems, and have complex and often strong effects on lower trophic levels. Agricultural intensification reduces habitat complexity, food web diversity and structure, and affects predator communities. Theory predicts that strong top-down cascades are less likely to occur as habitat and food web complexity decrease.
- 2To examine relationships between habitat complexity and predator effects, we excluded ants from coffee plants in coffee agroecosystems varying in vegetation complexity. Specifically, we studied the effects of eliminating ants on arthropod assemblages, herbivory, damage by the coffee berry borer and coffee yields in four sites differing in management intensification. We also sampled ant assemblages in each management type to see whether changes in ant assemblages relate to any observed changes in top-down effects.
- 3Removing ants did not change total arthropod densities, herbivory, coffee berry borer damage or coffee yields. Ants did affect densities of some arthropod orders, but did not affect densities of different feeding groups. The effects of ants on lower trophic levels did not change with coffee management intensity.
- 4Diversity and activity of ants on experimental plants did not change with coffee intensification, but the ant species composition differed.
- 5Although variation in habitat complexity may affect trophic cascades, manipulating predatory ants across a range of coffee agroecosystems varying in management intensity did not result in differing effects on arthropod assemblages, herbivory, coffee berry borer attack or coffee yields. Thus, there is no clear pattern that top-down effects of ants in coffee agroecosystems intensify or dampen with decreased habitat complexity.