We studied the avifauna of sun and shade coffee plantations and associated mid‐elevation habitats during the dry season of 1995. The three plantation types (Inga, Gliricidia, and sun) showed high faunistic similarities with each other and were both distinct and depauperate compared to matorral and forest patch habitats. Of all the coffee plantation habitats, Inga shade had the highest diversity. Species associated with wooded vegetation were more common in shade plantations, particularly in Inga. A second census showed a decline in bird numbers that was more pronounced in sun and Gliricidia than in Inga plantations. Overall, differences between the plantation types were small and all coffee plantations were less diverse than traditional coffee farms previously studied in nearby Chiapas, México. The relatively low bird diversity was probably due to the low stature, low tree species diversity, and heavy pruning of the canopy. These features reflect management practices that are common throughout Latin America. The most common species of birds in all coffee plantation habitats were common second‐growth or edge species; more specialized forest species were almost completely absent from plantations. Furthermore, many common matorral species were rare or absent from coffee plantations, even sun plantations with which matorral shares a similar superficial structure. Coffee plantations probably will only be important for avian diversity if a tall, taxonomically and structurally diverse canopy is maintained. We suggest this is most likely to occur on farms that are managed for a variety of products rather than those designated entirely for the production of coffee.

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Experimental work has established that vertebrates can have a large impact on the abundance of arthropods in temperate forest and grasslands, as well as on tropical islands. The importance of vertebrate insectivory has only rarely been evaluated for mainland tropical ecosystems. In this study, we used exclosures to measure the impact of birds on arthropods in Guatemalan coffee plantations. Variation in shade management on coffee farms provides a gradient of similar habitats that vary in the complexity of vegetative structure and floristics. We hypothesized that shaded coffee plantations, which support a higher abundance of insectivorous birds, would experience relatively greater levels of predation than would the sun coffee farms. We found a reduction (64–80%) in the number of large (> 5 mm in length) but not small arthropods in both coffee types which was consistent across most taxonomic groups and ecological guilds. We also found a small but significant increase in the frequency of herbivore damage on leaves in the exclosures. This level of predation suggests that birds may help in reducing herbivore numbers and is also consistent with food limitation for birds in coffee agroecosystems. However, the presence of shade did not have an effect on levels of insectivory.

We surveyed birds in cacao (Theobroma cacao) plantations in the state of Tabasco, Mexico. The shade canopy was planted by farmers and consisted of approximately 60 species of trees with no single dominant species. Canopy height averaged 15 m and the structure was multi-storied. We conducted 220 ten minute, 25 m radius point counts for birds and detected 1550 individuals from 81 species. The average number of birds/point and the expected diversity in a fixed number of individuals within the cacao surveyed were well within the range of other lowland habitats, including agricultural sites, that we have surveyed previously in neighbouring Chiapas. In the Tabascan cacao, the migrant group was composed, in part, of forest species, and dimorphic species were represented primarily by males, which in other areas are known to dominate forest or forest-like habitats. In contrast to the composition of migrant species, we found few resident forest specialists in Tabascan cacao. Instead, the tropical resident group was composed of large-bodied generalist species that use small patches of trees in open habitats. These results (moderate diversity, low numbers of forest specialists) differ from the few studies completed in 'rustic' cacao systems located near large tracts of forest. The planted shade cacao agroecosystem -at least in the absence of nearby forest -may have a limited value for conserving lost tropical forest bird diversity, but it provides habitat for woodlandassociated migratory species. Our results also indicate that the planted shade cacao plantations supported few small omnivorous or frugivorous species, probably because cacao itself, as well as the dominant shade trees, produce primarily mammal or wind dispersed fruit and seeds.