title: Current ecological understanding of fungal-like pathogens of fish: what lies beneath?
abstract: Despite increasingly sophisticated microbiological techniques, and long after the first discovery of microbes, basic knowledge is still lacking to fully appreciate the ecological importance of microbial parasites in fish. This is likely due to the nature of their habitats as many species of fish suffer from living beneath turbid water away from easy recording. However, fishes represent key ecosystem services for millions of people around the world and the absence of a functional ecological understanding of viruses, prokaryotes, and small eukaryotes in the maintenance of fish populations and of their diversity represents an inherent barrier to aquatic conservation and food security. Among recent emerging infectious diseases responsible for severe population declines in plant and animal taxa, fungal and fungal-like microbes have emerged as significant contributors. Here, we review the current knowledge gaps of fungal and fungal-like parasites and pathogens in fish and put them into an ecological perspective with direct implications for the monitoring of fungal fish pathogens in the wild, their phylogeography as well as their associated ecological impact on fish populations. With increasing fish movement around the world for farming, releases into the wild for sport fishing and human-driven habitat changes, it is expected, along with improved environmental monitoring of fungal and fungal-like infections, that the full extent of the impact of these pathogens on wild fish populations will soon emerge as a major threat to freshwater biodiversity.
authors.affiliation: Unité Mixte de Recherche Biologie des Organismes et Écosystèmes Aquatiques (IRD 207, CNRS 7208, MNHN, UPMC), Muséum National d'Histoire Naturelle Paris Cedex, France ; Centre for Conservation Ecology and Environmental Sciences, School of Applied Sciences, Bournemouth University Poole, Dorset, UK.
authors.forename: Rodolphe E
authors.initials: RE
authors.lastname: Gozlan
authors.affiliation: BC Centre for Aquatic Health Sciences Campbell River, BC, Canada.
authors.forename: Wyth L
authors.initials: WL
authors.lastname: Marshall
authors.affiliation: School of Biological Sciences, University of Sydney Sydney, NSW, Australia.
authors.forename: Osu
authors.initials: O
authors.lastname: Lilje
authors.affiliation: School of Biological Sciences, University of Sydney Sydney, NSW, Australia.
authors.forename: Casey N
authors.initials: CN
authors.lastname: Jessop
authors.affiliation: School of Biological Sciences, University of Sydney Sydney, NSW, Australia.
authors.forename: Frank H
authors.initials: FH
authors.lastname: Gleason
authors.affiliation: Centre for Conservation Ecology and Environmental Sciences, School of Applied Sciences, Bournemouth University Poole, Dorset, UK.
authors.forename: Demetra
authors.initials: D
authors.lastname: Andreou
keywords: Mesomycetozoea; Oomycota; aquatic; biodiversity; emerging infectious disease; extinction; global; vertebrate