title: The global susceptibility of coastal forage fish to competition by large jellyfish.
abstract: Competition between large jellyfish and forage fish for zooplankton prey is both a possible cause of jellyfish increases and a concern for the management of marine ecosystems and fisheries. Identifying principal factors affecting this competition is therefore important for marine management, but the lack of both good quality data and a robust theoretical framework have prevented general global analyses. Here, we present a general mechanistic food web model that considers fundamental differences in feeding modes and predation pressure between fish and jellyfish. The model predicts forage fish dominance at low primary production, and a shift towards jellyfish with increasing productivity, turbidity and fishing. We present an index of global ecosystem susceptibility to shifts in fish-jellyfish dominance that compares well with data on jellyfish distributions and trends. The results are a step towards better understanding the processes that govern jellyfish occurrences globally and highlight the advantage of considering feeding traits in ecosystem models.
authors.affiliation: Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, Kavalergården 6, 2920 Charlottenlund, Denmark niaz@aqua.dtu.dk.
authors.forename: Nicolas Azaña
authors.identifier: 0000-0002-9725-9646
authors.initials: NA
authors.lastname: Schnedler-Meyer
authors.affiliation: Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, Kavalergården 6, 2920 Charlottenlund, Denmark.
authors.forename: Patrizio
authors.initials: P
authors.lastname: Mariani
authors.affiliation: Centre for Ocean Life, National Institute for Aquatic Resources, Technical University of Denmark, Kavalergården 6, 2920 Charlottenlund, Denmark.
authors.forename: Thomas
authors.identifier: 0000-0002-3265-336X
authors.initials: T
authors.lastname: Kiørboe
mesh_terms: D000818:Animals; D003247:Conservation of Natural Resources; D017753:Ecosystem; D005398:Fisheries; D005399:Fishes; D020387:Food Chain; D037401:Scyphozoa
keywords: competition; environmental drivers; fish; jellyfish blooms; trait-based model; water clarity