Cool birds: first evidence of energy-saving nocturnal torpor in free-living common swifts Apus apus resting in their nests.

ABSTRACT: Daily torpor is a means of saving energy by controlled lowering of the metabolic rate (MR) during resting, usually coupled with a decrease in body temperature. We studied nocturnal daily torpor under natural conditions in free-living common swifts Apus apus resting in their nests as a family using two non-invasive approaches. First, we monitored nest temperature (T_nest) in up to 50 occupied nests per breeding season in 2010-2015. Drops in T_nest were the first indication of torpor. Among 16 673 observations, we detected 423 events of substantial drops in T_nest of on average 8.6°C. Second, we measured MR of the families inside nest-boxes prepared for calorimetric measurements during cold periods in the breeding seasons of 2017 and

SUBMITTER: Wellbrock AHJ 

PROVIDER: S-EPMC9006018 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature