title: Aerobic scope fails to explain the detrimental effects on growth resulting from warming and elevated CO2 in Atlantic halibut.
abstract: As a consequence of increasing atmospheric CO2, the world's oceans are becoming warmer and more acidic. Whilst the ecological effects of these changes are poorly understood, it has been suggested that fish performance including growth will be reduced mainly as a result of limitations in oxygen transport capacity. Contrary to the predictions given by the oxygen- and capacity-limited thermal tolerance hypothesis, we show that aerobic scope and cardiac performance of Atlantic halibut (Hippoglossus hippoglossus) increase following 14-16 weeks exposure to elevated temperatures and even more so in combination with CO2-acidified seawater. However, the increase does not translate into improved growth, demonstrating that oxygen uptake is not the limiting factor for growth performance at high temperatures. Instead, long-term exposure to CO2-acidified seawater reduces growth at temperatures that are frequently encountered by this species in nature, indicating that elevated atmospheric CO2 levels may have serious implications on fish populations in the future.
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, 405 30 Gothenburg, Sweden.
authors.forename: Albin
authors.initials: A
authors.lastname: Gräns
authors.forename: Fredrik
authors.initials: F
authors.lastname: Jutfelt
authors.forename: Erik
authors.initials: E
authors.lastname: Sandblom
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Jönsson
authors.forename: Kerstin
authors.initials: K
authors.lastname: Wiklander
authors.forename: Henrik
authors.initials: H
authors.lastname: Seth
authors.forename: Catharina
authors.initials: C
authors.lastname: Olsson
authors.forename: Sam
authors.initials: S
authors.lastname: Dupont
authors.forename: Olga
authors.initials: O
authors.lastname: Ortega-Martinez
authors.forename: Ingibjörg
authors.initials: I
authors.lastname: Einarsdottir
authors.forename: Björn Thrandur
authors.initials: BT
authors.lastname: Björnsson
authors.forename: Kristina
authors.initials: K
authors.lastname: Sundell
authors.forename: Michael
authors.initials: M
authors.lastname: Axelsson
mesh_terms: D000818:Animals; D001833:Body Temperature Regulation; D002245:Carbon Dioxide / Q000378:metabolism; D057231:Climate Change; D005432:Flounder / Q000254:growth & development / Q000502:physiology*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D010100:Oxygen / Q000378:metabolism
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen
keywords: Carbon dioxide; Climate change; OCLTT; Ocean acidification; Optimal temperature; Oxygen and capacity limited thermal tolerance; Oxygen consumption rate; Respirometry