Molecular diagnosis of bird-mediated pest consumption in tropical farmland

Biodiversity loss will likely have surprising and dramatic consequences for human wellbeing. Identifying species that benefit society represents a critical first step towards predicting the consequences of biodiversity loss. Though natural predators prevent billions of dollars in agricultural pest damage annually, characterizing which predators consume pests has proven challenging. Emerging molecular techniques may illuminate these interactions. In the countryside of Costa Rica, we identified avian predators of coffee’s most damaging insect pest, the coffee berry borer beetle (Coleoptera:Scolytidae Hypothenemus hampeii), by assaying 1430 fecal samples of 108 bird species for borer DNA. While feeding trials confirmed the efficacy of our approach, detection rates were low. Nevertheless, we identified six species that consume the borer. These species had narrow diet breadths, thin bills, and short wings; traits shared with borer predators in other systems. Borer predators were not threatened; therefore, safeguarding pest control necessitates managing species beyond those at risk of regional extinction by maintaining populations in farmland habitats. Generally, our results demonstrate potential for pairing molecular methods with ecological analyses to yield novel insights into species interactions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/2193-1801-3-630) contains supplementary material, which is available to authorized users

Bats in the anthropogenic matrix: Challenges and opportunities for the conservation of chiroptera and their ecosystem services in agricultural landscapes

Intensification in land-use and farming practices has had largely negative effects on bats, leading to population declines and concomitant losses of ecosystem services. Current trends in land-use change suggest that agricultural areas will further expand, while production systems may either experience further intensification (particularly in developing nations) or become more environmentally friendly (especially in Europe). In this chapter, we review the existing literature on how agricultural management affects the bat assemblages and the behavior of individual bat species, as well as the literature on provision of ecosystem services by bats (pest insect suppression and pollination) in agricultural systems. Bats show highly variable responses to habitat conversion, with no significant change in species richness or measures of activity or abundance. In contrast, intensification within agricultural systems (i.e., increased agrochemical inputs, reduction of natural structuring elements such as hedges, woods, and marshes) had more consistently negative effects on abundance and species richness. Agroforestry systems appear to mitigate negative consequences of habitat conversion and intensification, often having higher abundances and activity levels than natural areas. Across biomes, bats play key roles in limiting populations of arthropods by consuming various agricultural pests. In tropical areas, bats are key pollinators of several commercial fruit species. However, these substantial benefits may go unrecognized by farmers, who sometimes associate bats with ecosystem disservices such as crop raiding. Given the importance of bats for global food production, future agricultural management should focus on “wildlife-friendly” farming practices that allow more bats to exploit and persist in the anthropogenic matrix so as to enhance provision of ecosystem services. Pressing research topics include (1) a better understanding of how local-level versus landscape-level management practices interact to structure bat assemblages, (2) the effects of new pesticide classes and GM crops on bat populations, and (3) how increased documentation and valuation of the ecosystem services provided by bats could improve attitudes of producers toward their conservation

Diet of two sympatric insectivores bats (Chiroptera: Vespertilionidae) in the Cerrado of Central Brazil

We examined food habits of Vespertilionidae bats Myotis nigricans (Schinz, 1821) and Eptesicus furinalis (d'Orbigny, 1847) by fecal analysis in cerrado sensu stricto and gallery forests, within APA - Gama-Cabeça-de-Veado, Brasília, Distrito Federal, Brazil. Out of 20 fecal samples collected, seven were of Eptesicus furinalis and 13 of Myotis nigricans. The diet of E. furinalis included six orders of insects: Coleoptera (5/7 by items presence), Lepidoptera and Hymenoptera (3/7), Diptera, Hemiptera and Homoptera (1/7). The diet of M. nigricans included all the main orders consumed by E. furinalis (6/13, 4/13, 4/13, 3/13, 1/13, and 4/13 respectively) and one other order: Orthoptera (1/13). Homoptera, Diptera and Orthoptera were collected only in bats captured in gallery forest. There is 80% of overlap in the diet of these two species. Predation on species of Scarabeidae, Hesperiidae, Sphingidae and Saturniidae families confirms bats potential as biological control agents of pests in agricultural ecosystems.<br>Foi examinado o hábito alimentar das espécies de Vespertilionidae Myotis nigricans (Schinz, 1821) e Eptesicus furinalis (d'Orbigny, 1847) por meio de análise de amostras fecais coletadas em animais capturados em área de cerrado sensu stricto e matas de galeria, na APA - Gama-Cabeça-de-Veado, Brasília, Distrito Federal, Brasil. Um total de 20 amostras fecais foi analisado, sendo sete de E. furinalis e 13 de M. nigricans. A dieta de E. furinalis incluiu seis ordens de insetos: Coleoptera (5/7) (presença na amostra total), Lepidoptera e Hymenoptera (3/7), Diptera, Hemiptera e Homoptera (1/7). A dieta de M. nigricans incluiu todas as ordens consumidas por E. furinalis (6/13, 4/13, 4/13, 3/13, 1/13, and 4/13 respectively) e uma ordem a mais: Orthoptera (1/13). Homoptera, Diptera e Orthoptera só foram amostrados para morcegos capturados em mata de galeria. Há 80% de sobreposição na dieta destas duas espécies. A predação sobre espécies das famílias Scarabeidae, Hesperiidae, Sphingidae e Saturniidae confirma o potencial dos morcegos como agentes de controle biológicos de pragas em ecossistemas agrícolas