Summer dormancy in edible dormice (Glis glis) without energetic constraints

Area of Science:

• Ecology
• Animal Behavior
• Mammalogy

Background:

• Edible dormice (Glis glis) achieve exceptional longevity for small rodents, with average lifespans reaching 9 years.
• Their long life is linked to infrequent reproduction, primarily during mast seeding years, and a mysterious disappearance of populations in non-reproductive years.

Purpose of the Study:

• To investigate the duration of above-ground activity and body temperature profiles in edible dormice under semi-natural conditions.
• To understand the reasons behind the apparent vanishing of non-reproductive dormice populations.

Main Methods:

• Studied dormice in outdoor enclosures under semi-natural conditions.
• Monitored the duration of above-ground activity.
• Recorded body temperature profiles of a subset of animals.

Main Results:

• Non-reproductive dormice exhibited extremely short active seasons (<2 weeks).
• These animals spent over 10 months per year in dormancy in underground burrows.
• Summer dormancy occurred irrespective of energy constraints, climatic stress, or animal condition.

Conclusions:

• Edible dormice engage in almost year-round torpor, exceeding dormancy durations of all other known mammals.
• This extended dormancy is hypothesized to be a predator-avoidance strategy against avian predators.
• This unique survival strategy significantly contributes to the unusually high longevity observed in Glis glis.