Daubenton Bat Colonies Have "Flexible Social System"

A team of British scientists has discovered that the insect-eating bats have a "flexible social system," reports BBC.

Researchers from University of Leeds, U.K., observed the colonies of Daubenton's bats (Myotis daubentonii) in Yorkshire Dales National Park.

The research team found that the male and female bats were living at different altitudes. While the male bats spend time at higher altitudes, the female bats and their offspring swarmed the lower altitudes. At intermediate heights, both males and females lived alongside each other all year round. This is the first time scientists have documented the unusual behavior of Daubenton's bats. This kind of segregation is probably a way to get better access to food, warmth and other resources, according to a report in LiveScience.

The females were living at lower heights because the weather conditions were not suitable enough for them to stay at higher altitudes. Pregnant females need a lot of nourishment and also have to produce milk to feed their babies. It is not possible for the female bats to compete with the males at higher altitudes for food resources.

Male bats prefer to stay at higher altitudes so as to avoid parasites found close to baby bat nurseries. When the weather is wet and windy and there is no food, the males would just shut down their body temperature and sleep it out.

Surprisingly, the males and females living at intermediate heights were found to cohabit all year. It was previously thought that most of the bat species, including the Daubenton's bats, would live apart from the spring and swarm near caves to mate only in late summer.

However, the researchers found that the presumably healthier and dominant bats living in intermediate locations got an opportunity to mate with females much earlier than the other males who have to wait until the swarming season begins. The bats in mid-altitude territory were able to easily fulfill their feeding and mating needs.

The findings of the study are published in the journal PLOS ONE.