Overview
- University of Ottawa researchers report in Proceedings of the Royal Society B that hibernating queens endure multi-day submersion through limited underwater respiration, anaerobic metabolism, and profound metabolic depression.
- In controlled chambers, queens submerged in cold water for up to eight days drew down dissolved oxygen while continuously releasing carbon dioxide, indicating active respiration in water.
- Carbon dioxide production, used as a proxy for metabolism, fell from about 15.42 to 2.35 microliters per hour per gram after eight days of submersion, roughly one-sixth of pre-submersion levels.
- Lactate accumulated during submersion, and resurfaced queens showed several days of elevated breathing as they cleared this anaerobic byproduct and recovered.
- The physical mechanism for extracting oxygen from water remains unconfirmed, with a hypothesized trapped-air ‘physical gill,’ and researchers caution that repeated flooding could tax queens’ finite energy reserves as extreme precipitation increases.