Two In Tow
/ Post by Katie Billings of Polar Bears International
I have never seen a parental bond stronger than a mother polar bear with her cubs. Their entire lives are dedicated to caring for and protecting their young. Female polar bears begin mating on the ice in late April or early May (Eliasson, 2006, p.38). Mating lasts several days and the egg is fertilized in mid-May. Then an amazing process takes place. This adaptation female polar bears experience is called delayed implantation. Delayed implantation means that the pregnancy does not begin until another four months has passed. Why? Because female bears want to ensure that their babies have the best possible survival. In order to provide that security, female bears need to gain weight by hunting and storing fat, which will help her survive the future months in her maternity den. Those fat stores also are converted into milk supply for her cubs. Female bears need to hunt on the ice and maintain a weight around 300kg (660lbs) or else the egg will not develop.
At three months into the pregnancy, the mother bear moves into a maternity den in September and she will remain in her earthen home until late-February or mid-March when the cubs are ready to emerge (Eliasson, 2006, p.40). That means that momma bear is in her den for about seven months. Can you imagine living in a den for seven months, surviving off of your own body, giving birth, and supporting your young? It is truly a remarkable process. In the past, females could birth up to three cubs. In more recent years females typically have one or two cubs, if they are lucky. If the female manages to have two cubs, she has more work to do. The motherly love doesn’t stop there. Momma bear continues to raise her cubs as they embark on yet another life or death journey when they cross the ice for the first time. While on the ice, mother bears have to train their cubs with the “Polar Bear Survival Guide.” She teaches them to use their instincts and adaptations to hunt seals, swim, play, and protect themselves from large male polar bears. A mother polar bear will do anything to protect her offspring, even if that means sacrificing her own life.
As the Arctic ice continues to melt, female bears are having a harder time locating mates, finding maternal dens, and maintaining enough fat for egg development. If bears manage to have cubs, the females worry about hungry male bears looking for easy meals. National Geographic said, “Females face especially hard times. Malnourished males may kill and eat cubs-and even their mothers” (McGrath, 2011, p. 72). The sacrifice mother polar bears make for their cubs is incredible. When out on the tundra with explore.org, I had the opportunity to see the first “family” of the year. A family consists of a mother with two cubs. Watching them cross the land was like watching one of nature’s miracles. The mother guided the way as her two cubs tagged along behind. Their majestic journey has just begun. Seeing a mother polar bear and her cubs in the wild is one of the most empowering things I have ever witnessed. These bears, against all odds, have survived generations due to their adaptations and incredible family bonds. Unfortunately we know that global warming is impacting polar bear populations. The day mother bears can’t maintain enough weight to support cubs is the day we deprive our children and great-grandchildren of the incredible experiences mother nature provides us. To ensure the bear’s survival and the arrival of ice each year, look into your hearts and donate to organizations that support polar bears and are dedicated to their future survival.
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