Towards a food web based control strategy to mitigate an amphibian panzootic in agricultural landscapes

While the emerging amphibian disease chytridiomycosis is causing dramatic and ongoing biodiversity losses worldwide, sustainable strategies to mitigate this global threat to amphibians are currently missing. We here propose a conceptual framework for a novel biological mitigation strategy based on the increasing evidence that naturally occurring micropredators, such as protists, rotifers and crustaceans, are capable of using zoospores of the chytrid pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal) as a food source under controlled laboratory conditions. Pathogen predation may serve as a cost-efficient way to prevent chytridiomycosis outbreaks under natural conditions by reducing zoospore densities and thereby infection loads. This predator-pathogen relationship is not an isolated interaction, but is embedded in the aquatic food web structure that interacts with a wide range of environmental factors. Amphibian breeding ponds are increasingly associated to agricultural landscapes due to ongoing land use occupancy for food production, exposing these water bodies to a variety of environmental stressors such as agrochemical pollution, nutrient enrichment and cattle trampling. Environmental stressors may affect the composition and abundance of aquatic communities, while they can also exert sublethal effects that may reduce the zoospore removal efficiency of micropredators. By carefully controlling environmental stressors, trophic interactions may be steered to optimize chytrid predation with the aim of reducing zoospore densities to such extent that hosts and pathogens can sustainably coexist. We present a scientific outline of this novel concept and provide a framework for ongoing research to develop a complete mitigation strategy against chytridiomycosis based on such food web control.

Jaar van publicatie:2020

Toegankelijkheid:Open