title: Rapid biotic homogenization of marine fish assemblages.
abstract: The role human activities play in reshaping biodiversity is increasingly apparent in terrestrial ecosystems. However, the responses of entire marine assemblages are not well-understood, in part, because few monitoring programs incorporate both spatial and temporal replication. Here, we analyse an exceptionally comprehensive 29-year time series of North Atlantic groundfish assemblages monitored over 5° latitude to the west of Scotland. These fish assemblages show no systematic change in species richness through time, but steady change in species composition, leading to an increase in spatial homogenization: the species identity of colder northern localities increasingly resembles that of warmer southern localities. This biotic homogenization mirrors the spatial pattern of unevenly rising ocean temperatures over the same time period suggesting that climate change is primarily responsible for the spatial homogenization we observe. In this and other ecosystems, apparent constancy in species richness may mask major changes in species composition driven by anthropogenic change.
authors.affiliation: Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, Scotland, UK.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Magurran
authors.affiliation: Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, Scotland, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Dornelas
authors.affiliation: Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, Scotland, UK.
authors.forename: Faye
authors.initials: F
authors.lastname: Moyes
authors.affiliation: Department of Biology, University of Vermont, Burlington, Vermont 05405, USA.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Gotelli
authors.affiliation: School of Biology and Ecology, Sustainability Solutions Initiative, University of Maine, Orono, Maine 04469, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: McGill
mesh_terms: D000818:Animals; D001267:Atlantic Ocean; D044822:Biodiversity; D058448:Biota; D057231:Climate Change; D017753:Ecosystem; D005399:Fishes; D012606:Scotland; D062211:Spatio-Temporal Analysis; D013696:Temperature