Female brown bears in Sweden now frequently care for their offspring for an additional year finds a study published in Nature Communications this week. This change is associated with hunting regulation that protects mothers and their dependent cubs.
Joanie Van de Walle and colleagues analysed data on the reproductive strategy and survival of brown bears (Usus arctos) collected over more than 20 years. They show that an extended period of maternal care (up from 1.5 to 2.5 years) has been spreading in the population since the first observation in the mid-1990s. Although extended care means that the females have fewer breeding opportunities, the authors show that this cost is outweighed by a higher survival rate of mother and cubs given the combination of hunting regulation and intense hunting pressure.
In other animal species, hunting and harvesting have been linked to selection for a faster life cycle, as individuals must start reproducing early in order to maximize their opportunity to reproduce. In contrast, the new findings suggest that hunting and certain management regulations can interact to slow down a species’ life cycle.