Influence of water temperature and oxygenation on the aerobic metabolic scope of Atlantic cod (Gadus morhua)

Abstract

Environmental influences (temperature and oxygenation) on cod metabolism and their impact on the ecology of this species were investigated. Limiting oxygen concentration curves (O 2 level ranging between 15 and 100% air saturation) were established at 2, 5 and 10°C. The standard metabolic rate (SMR), the maximum metabolic rate and the metabolic scope were then modelled as functions of temperature and/or oxygen saturation. The mean SMR at 2, 5 and 10°C were 19.8±4.9, 30.8±6.1 and 54.3±4.1 mg O 2 h −1 kg −1 , respectively. Between 2 and 5°C, the active metabolic rate of cod almost doubled from 65 to 120 mg O 2 h −1 kg −1 , to reach 177 mg O 2 h −1 kg −1 at 10°C. In terms of metabolic scope (MS), the temperature rise from 2 to 5°C resulted in a twofold increase from 45 to 89 mg O 2 h −1 kg −1 , with MS reaching 123 mg O 2 h −1 kg −1 at 10°C. Our proposed model describing the impact of temperature and oxygen level provides new insight into the energetic interactions which govern the relationship between Atlantic cod and its environment. We reexamined published experimental and field studies from the angle of the regulation of metabolic power. We suggest that, when faced with heterogeneous or unstable hydrological conditions, cod tend to behaviourally maximise their metabolic scope. Through this adaptive response, fish reduce energy budgeting conflicts and presumably increase the probability of routinely operating away from lethal boundaries.

Effect of temperature and dissolved oxygen on swimming performance in crucian carp

“…These results are consistent with most published studies of fish species (Hammer 1995, Claireaux et al 2000, Lee et al 2003b, Fangue et al 2008, Yan et al 2012. The reduction in swimming performance with decreasing temperature could stem from changes in both the external and internal environment of the fish.…”

“…Temperature and DO were selected as the environmental factors to be modified because they are the most frequently encountered and environmentally relevant physiological challenges (Randall & Brauner 1991, Claireaux et al 2000. The low temperature (10°C) selected in this study simulated the environment of the crucian carp in winter, whereas the hypoxic level simulated the extreme hypoxia situation in summer according to data on local water bodies in Chongqing, China.…”

Oxygen limited thermal tolerance in fish?

“…The relationship between temperature dependent growth rates and aerobic scope may follow this pattern. Aerobic scope and growth rate were found related in a population of cod (Claireaux et al, 2000). Growth curves similarly shaped as in Fig.…”

Influence of ambient oxygenation and temperature on metabolic scope and scope for heart rate in the common sole Solea solea

“…Temperature and oxygen are, respectively, potent controlling and limiting factors of fish metabolism, and they interact through their joint effects on MS (Fry 1971, Neill & Bryan 1991, Claireaux & Lagardère 1999. Using data from Chabot & Dutil (1999), Claireaux et al (2000) examined the consequences of reduced MS in Atlantic cod Gadus morhua exposed to hypoxia. These authors showed that a linear relationship could be established between the MS of cod and its growth.…”