Snakes are characterized by distinct foraging strategies, from ambush to active hunting, which can be predicted to substantially affect the energy budget as a result of differential activity rates and feeding frequencies. Intense foraging activity and continuously upregulated viscera as a result of frequent feeding leads to a higher standard metabolic rate (SMR) in active than in ambush predators. Conversely, the costs of digestion (Specific Dynamic Action—SDA) are expected to be higher in ambush predators following the substantial remodelling of the gut upon ingestion of a meal after a long fasting period. This prediction was tested on an interspecific scale using a large multispecies dataset (> 40 species) obtained from published sources. I found that the metabolic scope and duration of SDA tended to reach higher values in ambush than in active predators, which probably reflects the greater magnitude of postprandial physiological upregulation in the former. In contrast, the SDA energy expenditure appeared to be unrelated to the foraging mode. The costs of visceral activation conceivably are not negligible, but represent a minor part of the total costs of digestion, possibly not large enough to elicit a foraging-mode driven variation in SDA energy expenditure. Non-mutually exclusive is that the higher costs of structural upregulation in ambush predators are balanced by the improved, thus potentially less expensive, functional performance of the more efficient intestines. I finally suggest that ambush predators may be less susceptible than active predators to the metabolic ‘meltdown effect’ driven by climate change.

蛇的特点是不同的觅食策略，从伏击到主动狩猎，可以预测，由于不同的活动率和进食频率，它们会显着影响能量收支。由于频繁喂食，强烈的觅食活动和不断上调的内脏导致活跃的标准代谢率 (SMR) 高于伏击捕食者。相反，在长时间禁食后摄入食物后肠道发生显着重塑后，伏击捕食者的消化成本（特定动态行动-SDA）预计会更高。使用从已发布来源获得的大型多物种数据集（> 40 个物种）在种间尺度上测试了这一预测。我发现SDA的代谢范围和持续时间在伏击中往往比在主动捕食者中达到更高的值，这可能反映了前者的餐后生理上调幅度更大。相比之下，SDA 能量消耗似乎与觅食模式无关。可以想象，内脏激活的成本不可忽略，但只占消化总成本的一小部分，可能不足以引起觅食模式驱动的 SDA 能量消耗变化。非互斥的是，伏击捕食者结构上调的更高成本与更有效的肠道功能性能的改善、因此可能更便宜的功能性能相平衡。