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Published on: September 4, 2016
Birds as predators in tropical agroforestry systems
Sunshine A Van Bael1, Stacy M Philpott, Russell Greenberg
1Smithsonian Tropical Research Institute, Unit 0948, APO, AA 34002, USA. vanbaels@si.edu
Ecology
|May 17, 2008
Summary
Insectivorous birds significantly reduce arthropod populations and plant damage across various habitats. Bird predation effects are strongest in agroforestry systems with diverse bird communities, especially when migratory birds are present.
Area of Science:
- Ecology
- Agricultural Science
- Ornithology
Background:
- Insectivorous birds play a role in controlling arthropod populations and mitigating plant damage.
- The effectiveness of bird predation varies based on factors like habitat complexity and species diversity.
- Agroforestry systems offer a unique context to study bird predation due to their distinct characteristics.
Purpose of the Study:
- To determine if birds consistently reduce arthropod prey and plant damage in forests and agroforestry systems.
- To compare the magnitude of bird predation effects between forests and agroforestry systems.
- To investigate how bird predation varies within agroforestry systems based on plant layer, migratory bird presence, and bird diversity.
Main Methods:
- Analysis of data from bird exclosure studies conducted in forest and agroforestry environments.
- Comparison of arthropod abundances and plant damage in the presence and absence of birds.
- Focus on agroforestry systems to examine predation differences between canopy and understory, with and without migratory birds, and correlation with bird diversity.
Main Results:
- Birds consistently reduce overall arthropods, herbivores, carnivores, and plant damage across all studied systems.
- No significant difference in bird predation effects was found between agroforestry systems and forests.
- Within agroforestry systems, bird predation was more pronounced in the canopy than the crop layer, intensified by migratory birds, and positively correlated with bird diversity.
Conclusions:
- Bird predation is a significant top-down control on arthropod populations in both forests and agroforestry systems.
- Agroforestry systems, particularly those with higher bird diversity (including migratory species), exhibit stronger predator effects.
- Habitat and predator diversity are key factors influencing the efficacy of bird predation, suggesting potential for integrated pest management strategies.
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