A Whale of a Baby
by Rebecca Hurwitz with the help of biologist Wendy Szaniszlo, Tofino
Every spring brings a baby boom on the West coast as the grey whales return with their young from their winter in Baja, Mexico. As a new mom myself, I wonder what it takes to be a mama whale? While we know little about the details of the grey whale reproductive cycle, there are certainly some similarities and differences between us and our mammal relatives.
In our part of the world, pregnant women are offered much support and people are suddenly happy to assist with everyday tasks. I somehow doubt that grey whale cows are offered so much support during their pregnancy. In October, pregnant females lead the migration south from Alaska. There isn't a lot of opportunity for assistance. No one can cook them dinner while they put up their feet and they certainly can't be offered a lift down south. In fact, the males play no apparent role in the lives of their offspring beyond conception.
Like humans, whales must increase their caloric intake during pregnancy to pack on a healthy amount of weight to provide for the baby. Most of this feeding takes place during the summer in Northern waters when they gain up to 30% of their body weight. We don't actually know how much weight whales gain when they are pregnant, but thank goodness they have the buoyancy provided by the water to help ease the strain.
After thirteen and a half months gestation the calf is born. As mammals, we share the characteristic of birthing live young. Whales generally give birth to one calf--multiple births are extremely rare in the cetacean world. While we don't know if whales have developed any pain management techniques during labour, it could be said that they have pioneered water birth. Grey whale calving takes place in warm, shallow waters and the young make their appearance head first, which is unusual for cetaceans.
Our newborns are so dependent on their parents that we refer to the first part of their lives as the 4th trimester. We feed them, clothe them and change their diapers while their body systems continue to de?velop. A whale calf instinctively swims to the surface within seconds for its first breath; with the help of its mother. Within 30 minutes of its birth, the baby whale can swim. Calves nurse for the first seven or eight months on extremely rich milk, which is more than 50% fat. Human milk by comparison is only 2% fat! Baby whales drink 50-80 pounds of milk each day, which helps them to grow from their birth length of 4.6m to 7m by the time they are weaning.
By late February, mothers and calves must think about making their return journey to Alaska. Their 9,000 km journey will bring the young through our waters for the first time. When you spot them off of our coast give them a big round of applause. This is the first of their many migrations. You've come a long way baby!
Rebecca Hurwitz is not a whale expert, but is learning more about babies every day from her new daughter Calla. She hopes to be spotting whales from the Wild Pacific Trail any day now and is looking forward to the Chowder Chowdown!
Watch for opportunities to join Wendy Szaniszlo in action throughout the Pacific Rim Whale Festival at one of her many talks and interactive adventures - don't miss the boat!
Grey whales give birth to their offspring in Baja and return with their young from their winter in Mexico. During their first migration north, mothers and their calves feed in the waters of Clayoquot and Barkley Sound.