全球变化知识资源中心

Variation in water temperature can have important effects on the energetics underlying metabolism, growth, and reproduction of many organisms. In order to anticipate how a species' allocation of energy may change in a warming ocean, we need to know the degree to which processes such as metabolic rate change with temperature (i.e., the thermal sensitivity of metabolism, Qio). In the context of long-term climate change, it will also be helpful to know whether local populations that experience different thermal regimes exhibit differences in thermal sensitivity. If so, it would indicate that thermal sensitivities of populations may adjust via acclimation or adaptation. We measured metabolic rates of Woolly Sculpin collected from two distant populations (Santa Cruz (SC) and Los Angeles (LA) counties, California, USA) and housed in a common environment. Using respirometry, we estimated resting mass-specific oxygen consumption (MO2) and calculated metabolic rates (MR) at temperatures of 12 degrees C, 16 degrees C, and 20 degrees C for 59 fish. The Q(10) value across this range of temperatures was 2.92. Populations did not differ with respect to overall MO2, nor did they vary in their degree of thermal sensitivity. However, the LA population had greater variation in MO2 among individuals when compared to the SC population. Larger variation in overall MO2 among individuals within specific populations may reflect greater genetic diversity, and this may buffer some populations against the effect of future increases in water temperature.