Effects of Body Mass and Temperature on Standard Metabolic Rate in the Eastern Diamondback Rattlesnake (Crotalus adamanteus)

Abstract

Abstract Determining the consequences of body size and body temperature (Tb) variation is critical to understanding many aspects of snake ecology, because size and temperature play such important roles in the biology of ectotherms. Here, we investigate the effects of body size and temperature variation on the energetics of the largest species of rattlesnake, the Eastern Diamondback Rattlesnake (Crotalus adamanteus). Specifically, we measured oxygen consumption to estimate the standard metabolic rate (SMR) of five C. adamanteus (mass range 800–4980 g) at 5-degree increments from 5–35 C. A multiple regression model indicated that SMR increased with body size and temperature. Q10s were generally high (range 1.82–4.20) compared to other squamates but were similar to the high values calculated for other large rattlesnakes. An energy balance model for C. adamanteus predicted that as Tb increases, so must prey consumption to meet annual SMR energy demands. Thus, Tb variation likely affects patterns of energy acq...