Deforestation, host community structure, and amphibian disease risk

Author(s)

Guilherme Becker, C. ^{[1, 2]} ; Rodriguez, David ^[3] ; Longo, Ana V. ^[1] ; Felipe Toledo, L. ^[4] ; Lambertini, Carolina ^[4] ; Leite, Domingos S. ^[4] ; Haddad, Cello F. B. ^[2] ; Zamudio, Kelly R. ^[1]

Affiliation

^[1] Cornell Univ, Dept Ecol & Evolutionary Biol, Ithaca, NY 14853 - USA

^[2] Univ Estadual Paulista, Dept Zool, BR-13506 Rio Claro, SP - Brazil

^[3] Texas State Univ, Dept Biol, San Marcos, TX 78666 - USA

^[4] Univ Estadual Campinas, Dept Biol Anim, BR-13083 Campinas, SP - Brazil

• Document type: Journal article
• Source: BASIC AND APPLIED ECOLOGY; v. 17, n. 1, p. 72-80, FEB 2016.
• Web of Science Citations: 9

Abstract

Habitat disturbances and the emergence of the chytrid fungus Batrachochytrium dendrobatidis (Bd) are linked to accelerated amphibian declines. Deforestation can directly alter amphibian community structure through abiotic and biotic mechanisms including shifts in local microclimates and species interactions. Changes in amphibian community attributes, in turn, potentially impact Bd transmission dynamics, and thus also have an indirect role in biodiversity persistence. Here, we tested whether deforestation influences Bd infections through shifts in amphibian community structure, including species richness, community composition, total host density, and host biomass. We surveyed 22 temperate and tropical amphibian communities across gradients of deforestation in the U.S. and Brazil, and we experimentally exposed a representative subsample of each amphibian community to standardized Bd zoospore loads in mesocosms under controlled microclimate. We found that denser temperate amphibian communities commonly found at pristine sites showed higher Bd loads when microclimates were held constant. In contrast, tropical amphibian communities found at pristine forest sites carried lower Bd infection loads in the absence of variable microclimates, likely due to their host species composition. Previous host exposure to the pathogen in tropical communities also played an important role in determining infection loads; we identified a negative association between Bd infection loads observed in the wild and in the laboratory. Our results highlight that deforestation can have cascading biotic effects on disease risk, and that quantifying the net contribution of host community attributes to Bd infections will help us identify specific drivers of disease and inform conservation strategies. (AU)

• FAPESP's process: 11/51694-7 - Into the heart of an epidemic: a US-Brazil collaboration for integrative studies of the amphibian-killing fungus in Brazil
• Grantee: Luis Felipe de Toledo Ramos Pereira
• Support Opportunities: Regular Research Grants
• FAPESP's process: 08/50928-1 - Speciation of frogs in high-altitude environments
• Grantee: Célio Fernando Baptista Haddad
• Support Opportunities: Research Projects - Thematic Grants