Brown bear mothers in Sweden are apparently changing their reproductive strategy in response to hunting, according to a new study (Van de Walle et al., 2018). The study found that prior to 2005, only about 7 percent of brown bear mothers kept their cubs longer than a year and a half. Between 2005 and 2015, however, more than 36 percent of moms held onto their cubs an extra year.
Hunting pressure on bears in Sweden is high, but a relatively recent law making it illegal to hunt mother bears helps explain the behavioral shift. Holding onto her cubs keeps a female bear safer and allows the cubs an extra year to develop under her care.
Long-term ramifications remain to be seen, but study coauthor Dr. Jon Swenson of the Norwegian University of Life Sciences sums it up: “Man is now an evolutionary force in the lives of the bears.”