title: Physiological constraints to climate warming in fish follow principles of plastic floors and concrete ceilings.
abstract: Understanding the resilience of aquatic ectothermic animals to climate warming has been hindered by the absence of experimental systems experiencing warming across relevant timescales (for example, decades). Here, we examine European perch (Perca fluviatilis, L.) from the Biotest enclosure, a unique coastal ecosystem that maintains natural thermal fluctuations but has been warmed by 5-10 °C by a nuclear power plant for over three decades. We show that Biotest perch grow faster and display thermally compensated resting cardiorespiratory functions compared with reference perch living at natural temperatures in adjacent waters. However, maximum cardiorespiratory capacities and heat tolerance limits exhibit limited or no thermal compensation when compared with acutely heated reference perch. We propose that while basal energy requirements and resting cardiorespiratory functions (floors) are thermally plastic, maximum capacities and upper critical heat limits (ceilings) are much less flexible and thus will limit the adaptive capacity of fishes in a warming climate.
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, Gothenburg 405 30, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Sandblom
authors.affiliation: University of Tasmania and CSIRO Agriculture Flagship, Tasmania, Hobart 7000, Australia.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Clark
authors.affiliation: Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Box 234, Skara 532 23, Sweden.
authors.forename: Albin
authors.initials: A
authors.lastname: Gräns
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, Gothenburg 405 30, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Ekström
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, Gothenburg 405 30, Sweden.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Brijs
authors.affiliation: Department of Animal Ecology/Evolutionary Biology Centre, Uppsala University, Box 592, Uppsala 751 24, Sweden.
authors.forename: L Fredrik
authors.initials: LF
authors.lastname: Sundström
authors.affiliation: Department of Aquatic Resources, Institute of Coastal Research, Swedish University of Agricultural Sciences, Skolgatan 6, Öregrund 742 42, Sweden.
authors.forename: Anne
authors.initials: A
authors.lastname: Odelström
authors.affiliation: Department of Aquatic Resources, Institute of Coastal Research, Swedish University of Agricultural Sciences, Skolgatan 6, Öregrund 742 42, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Adill
authors.affiliation: Department of Aquatic Resources, Institute of Coastal Research, Swedish University of Agricultural Sciences, Skolgatan 6, Öregrund 742 42, Sweden.
authors.forename: Teija
authors.initials: T
authors.lastname: Aho
authors.affiliation: Department of Biology, Norwegian University of Science and Technology, Trondheim NO-7491, Norway.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Jutfelt
mesh_terms: D000818:Animals; D003252:Construction Materials; D005843:Geography; D057232:Global Warming; D006321:Heart / Q000502:physiology; D008168:Lung / Q000502:physiology; D010471:Perches / Q000254:growth & development / Q000502:physiology*; D010969:Plastics; D012146:Rest
chemical_list: D010969:Plastics