Migratory bird community structure in oil palm (Elaies guineensis) plantations and native forest fragments in southern Mexico

Abstract

Oil palm (Elaies guineensis) plantations are among the fastest growing agroecosystems in the Neotropics, but little is known about how Neotropical birds use oil palm habitats. To better understand the potential value of oil palm as an overwintering habitat for migratory birds, we surveyed birds in oil palm and native forest remnants in Tabasco, Mexico, from 19 December 2017 to 27 March 2018. We collected data on bird abundance and vegetative structure and used generalized linear models and multivariate analysis to assess how oil palm development influenced migrant bird diversity, community assemblages, and abundance. We found that species richness of migratory birds tended to be higher in forest patches than in oil palm, that community assemblages of migratory birds differed between native forest and oil palm plantations, and that differences in migratory bird abundance, and subsequent changes in community assemblages were driven by differences between native forest and oil palm plantations in vegetative structure. The bird community of native forest was characterized by migrant species sensitive to forest loss that forage low in the understory and in the leaf litter, whereas the bird community of oil palm plantations was represented by generalist species that occupy a wider range of foraging niches. Our results suggest that most species of migrant birds responded positively to several forest structural features and that integrating more native trees and increasing the amount of understory vegetation in oil palm plantations may increase the value of working landscapes for migratory birds.

Winter Territoriality of the American Redstart in Oil Palm Plantations

“…Although considered a suboptimal habitat for the American Redstarts in the wintering grounds, oil palm plantations were still commonly used whereby multiple individuals established territories [15,34]. Winter territoriality and sexual segregation have been shown to exist in American Redstarts overwintering in more natural forested habitats in the neotropics [9,31].…”

“…In the case of the American Redstart, prey availability, influenced in part by humidity, play an important role in habitat quality for individuals inhabiting different forest types [41,47]. In Venezuelan shade coffee [14], citrus orchards in Jamaica [48], and oil palm plantations in Mexico [34,49], the observed higher densities of Redstarts, when compared with native vegetation could lead one to believe that these agroecosystems provide similar or higher quality habitats compared to native forest. Further assessments in citrus and oil palm plantations, using distributional and individual indicators, showed that these monocultures likely serve as poorer habitats for American Redstarts, as suggested by significantly lower body condition, sex and age segregation, and differences in territory size ( [15,48], Figure 1).…”

“…This process resulted in just a few secondary forest remnants in lower elevations. The climate in the region is characterized by an average temperature of 24 Mist-netting was used to capture birds to assess habitat quality through various indicators, including species abundance, community composition, fat loads, mass, and age and sex segregation [15,34]. Concurrently with bird captures (see Oliveira et al [34]), we outfitted 16 American Redstarts with 0.3 g radio telemetry transmitters (Advanced Telemetry Systems model no.…”

“…Although American Redstarts tend to select undisturbed forest habitats during the winter [28], populations will use a diversity of other habitats, from forest edges, young secondary forests, and regenerating pasture [29,30] as well as shade coffee plantations in Puerto Rico, Jamaica and Venezuela [14,20,31], cacao plantations in Mexico [32], citrus farms in Jamaica [31], and oil palm plantations in southern Mexico [33,34]. Oil palm cultivation is a rapidly expanding agroecosystem in the neotropics where it often replaces secondary forest or pasture [35].…”