Temperature dependence of fish performance in the wild: links with species biogeography and physiological thermal tolerance

Abstract

Summary Temperature strongly regulates the distribution and fitness of ectotherms, and many studies have measured the temperature dependence of physiological performance in controlled laboratory settings. In contrast, little is known about how temperature influences ectotherm performance in the wild, so the ecological significance of physiological performance as measured in the laboratory is unclear. Our aim was to measure the temperature dependence of performance in the wild for several species of fishes and to explore how temperatures that maximize performance in the wild (ToptE) are related to species biogeographies. We gathered body activity and growth data from the wild for nine tropical and temperate fish species, and by fitting thermal performance curves to these data, compared ToptE to species‐specific warm range boundary temperatures (the average temperature of the warmest month at equatorward range limits). To explore the degree to which trends in the wild reflect trends in physiological performance measured in the laboratory, we also compiled published data on the temperature dependence of aerobic metabolic scope in fishes and compared these to our wild fish data. We found ToptE in the wild was strongly correlated with warm range boundary temperatures, and that the difference between these two temperatures (the ‘environmental heating tolerance’) was smaller for more‐tropical species. Comparison with laboratory data revealed that ToptE approaches warm boundary temperatures in the wild at the same rate that the optimal temperature for aerobic scope (ToptAS) approaches upper critical temperatures (upper Tcrit) for aerobic scope in the laboratory, meaning that environmental heating tolerances in wild fishes closely mirror physiological heating tolerance (i.e. upper Tcrit − ToptAS) in captive fishes. Our comparison of field‐ and laboratory‐derived data highlights the ecological significance of aerobic metabolic scope in fishes and suggests wild fish species tend to perform best near the highest temperatures encountered in their range while maintaining a safety margin from the deleterious effects of upper critical temperatures.

Oxygen- and capacity-limited thermal tolerance: bridging ecology and physiology

“…The oxygen-and capacity-limited thermal tolerance (OCLTT) concept (Box 1), developed over the last two decades, has been proposed to meet these challenges and to provide a framework explaining how physiological mechanisms co-define an animal's fundamental and realised thermal niches (see Glossary), with a focus on critical life stages (for early summaries of OCLTT, see Pörtner, 2001Pörtner, , 2002; for thermal niches, see Pörtner et al, 2010;Deutsch et al, 2015;Payne et al, 2016). The basic idea underlying the OCLTT is that once temperatures approach limiting values, constraints on the capacity of an animal to supply oxygen to tissues to meet demand cause a progressive decline in performance (e.g.…”

“…Pörtner and Giomi et al, 2014), with consequences at the ecosystem level (e.g. Del Raye and Weng, 2015;Payne et al, 2016). OCLTT considers that most routine performances are fuelled sustainably by aerobic metabolism in excess of standard metabolic rate (SMR) and largely exclude anaerobic metabolism.…”

Poleward shift in large‐river fish communities detected with a novel meta‐analysis framework

“…Buisson, Grenouillet, Villéger, Canal, & Laffaille, 2013;Villéger, Blanchet, Beauchard, Oberdorff, & Brosse, 2011); (4) plasticity or limitations of physiological adaptation (e.g. Payne et al, 2016;Sandblom et al, 2016); (5) phenological changes (e.g. earlier or later fish migration or reproduction period; Crozier, Scheuerell, & Zabel, 2011;Tao et al, 2018); and (6) changes in size structure at community level (i.e.…”

A 12-year record of intertidal barnacle recruitment in Atlantic Canada (2005–2016): relationships with sea surface temperature and phytoplankton abundance

“…Sea surface temperature (SST) and coastal phytoplankton abundance are often important drivers of intertidal barnacle recruitment (Menge & Menge, 2013; Mazzuco et al, 2015). While water temperature universally affects the performance of aquatic ectotherms (Payne et al, 2016; Seabra et al, 2016), phytoplankton feeds the pelagic nauplius larvae (the stages preceding the cyprid stage) and recruits of barnacles, as they are filter-feeders (Singarajah, Moyse & Knight-Jones, 1967; Anderson, 1994; Jarrett, 2003; Gyory, Pineda & Solow, 2013). Therefore, our second objective is to evaluate how barnacle recruitment was related to SST and phytoplankton abundance during our study period in search of signals of external forcing in this system.…”