PS 19-20
Bird communities associated to agroecosystems in central Chile
The agricultural matrix that runs from ocean to mountains has been part of Mediterranean-climate ecosystems for centuries and is the primary factor in why these systems are among the most threatened on Earth. Advancing our understanding of ecology is critical in conservation planning in the Chilean Mediterranean ecosystem. The goal of this study was to determine how agricultural landscapes affect bird abundance and richness in central Chile. Bird survey plots were done at 111 locations of conventionally managed agricultural areas. The surveyed areas were characterized at local (50 m) and landscape (500 m) scales through direct observation and aerial photographs for two seasons. The effects of land covers, categorized as annual crops-fallow-grasslands (A-F-G), yards and constructions (Y-C), fruit orchards (Fruit) and native vegetation (Native), were evaluated as the percentage of bird species whose abundance was significantly affected. Generalized linear models were used to analyze the relationship among birds and agricultural land cover type as well as the influences of scale and season.
Results/Conclusions
The results showed that 42 species of birds use agricultural landscapes as habitat during both seasons, which belong to 22 bird families. The bird family most frequently found was Tyrannidae (n=5) and Emberizidae (n=5). The bird species richness was directly related to the presence of shrub hedgerows and native vegetation, whereas the abundance of birds was related to low strata crops (A-F-G). It was found that granivore species are favored by low strata crops (A-F-G) while omnivore species are favored by low and high strata crops (Fruit orchards). Season had the strongest effect on insectivore detection rates and exotic species were positively correlated with the built environment (yards and constructions). These findings suggest that there is great potential for bird conservation in Chile’s agroecosystems and that diversified agriculture is important in order to favor conservation of different bird communities.