Avian species identity drives predation success in tropical cacao agroforestry

Abstract

Summary1. Avian ecosystem services such as the suppression of pests are considered to be of high ecological and economic importance in a range of ecosystems, especially in tropical agroforestry. However, how bird predation success is related to the diversity and composition of the bird community, as well as local and landscape factors, is poorly understood. 2. We quantified arthropod predation in relation to the identity and diversity of insectivorous birds using experimental exposure of artificial, caterpillar-like prey in 15 smallholder cacao agroforestry systems differing in local shade-tree management and distance to primary forest. The bird community was assessed using both mist-netting (targeting active understorey insectivores) and point counts (higher completeness of species inventories). 3. Bird predation was not related to local shade-tree management or overall bird species diversity, but to the activity of insectivorous bird species and the proximity to primary forest. Insectivore activity was best predicted by mist-netting-based data, not by point counts. We identified the abundant Indonesian endemic lemon-bellied white-eye Zosterops chloris as the main driver of predation on artificial prey. 4. Synthesis and applications. The suppression of arthropods is a major ecosystem service provided by insectivorous birds in agricultural systems world-wide, potentially reducing herbivore damage on plants and increasing yields. Our results show that avian predation success can be driven by single and abundant insectivorous species, rather than by overall bird species richness. Forest proximity was important for enhancing the density of this key species, but did also promote bird species richness. Hence, our findings are both of economical as well as ecological interest because the conservation of nearby forest remnants will likely benefit human needs and biodiversity conservation alike.

Landscape processes underpinning bird persistence and avian-mediated pest control in fragmented landscapes

“…For example, Puckett and colleagues observed the majority of avian predators species (76%) foraging mainly within 20 m of the woody edge in temperate maize plantations ). Additionally, Maas and colleagues found higher number of predations marks by birds near forest edges in tropical cacao agroforestry, in an experimental study using plasticine caterpillars (Maas et al 2015).…”

“…Insectivorous birds provide significant pest control services , Maas et al 2015, and may complement or replace chemical-based pest control strategies agricultural systems , Maas et al 2015. However, the links between landscape structure and avianmediated insect pest control services are poorly known.…”

“…invertebrates Lucey & Hill 2012), avian predators Maas et al 2015;Boesing et al in review), and small mammals . Given that spillover may provide key ecological services in agricultural fields, understanding the role of landscape structure on spillover regulation is an important component of efforts to design and manage multifunctional agricultural landscapes.…”

“…In addition, birds have a diverse range of functional traits, which allows them to use a variety of resources and provide an associated diversity of ecosystem services . While our understanding of the influence of landscape structure bird species composition inside native habitat patches Martensen et al 2012) and in different matrix types Maas et al 2015) is growing, how landscape structure and matrix composition influence avian-cross habitat spillover…”

Efeitos da estrutura da paisagem sobre o controle biológico do bicho-mineiro-do-cafeeiro (Leucoptera coffeella, Lepidoptera: Lyonetiidae) provido por aves e morcegos

“…Although some studies have identified predatory birds controlling pests in coffee and cacao plantations Maas et al 2015), more studies are needed to identify the vertebrate predators that provide pest control services in coffee plantations in Brazil. Also basic biological information regarding the potential negative interactions between vertebrate and arthropod predators in coffee plantations is needed to understand how to maximize this service.…”