November 8, 2011
Guest Post: Following a Family of Sperm Whales
Editor’s Note: Guest blogger Shane Gero is a Ph.D. candidate at Dalhousie University in Nova Scotia and a lead researcher for the Dominica Sperm Whale Project.
I met Enigma when he was only a few months old. He was about three meters long and probably weighed over a ton.
That’s about average for a newborn sperm whale. When he reaches full size, in about 25 years, Enigma might be as long as 18 meters and weigh over 50 tons.
I have been following Enigma’s family since before he was born. I have spent literally thousands of hours at sea following them and about 20 other families of sperm whales which live in the eastern Caribbean Sea.
It has really been the first time that anyone has come to know these leviathans from the deep as individuals with personalities, as brothers and sisters or as mothers and babysitters, and as a community of families each with their own ways of doing things, their own dialects, and their own cultures.
Sperm whale relationships are very much like our social lives — more so than many might like to admit. The main difference is the most obvious, they live in the ocean. You see, most of the ocean is actually dark. Only a thin layer at the surface gets any light from the sun. For a sperm whale, life is really in the darkness of the deep.
I jokingly call them “surfacers” rather than “divers” because an adult female, like Enigma’s mother Mysterio, will spend over 80 percent of her life in the darkness of the deep ocean feeding. She will only spend about 10 to 15 minutes of every hour in the part of the ocean that sunlight touches and where I can observe her interacting with other members of her family.
As a result, while Mysterio’s eyesight is good both above and below the water, her world is dominated by sound. Just like bats, sperm whales have evolved a system of echolocation to “see” in the dark. Their unique nose, which houses the most powerful natural sonar system, has allowed them to exploit the deepest parts of the ocean that very few other mammals can, and as a result has made them a significant part of the ocean ecosystem. Globally, sperm whales can eat as much squid as all of humanity’s fisheries combined.
But Enigma is still young, so he doesn’t dive deeply with his mother to hunt for squid yet. His aunt, Pinchy, will babysit him while she is up at the surface to nurse Enigma’s younger cousin, Tweak.
Sperm whale society is matrilineal. Grandmothers, mothers, and their daughters live together for life. Females stick together because “it takes a village” to raise a sperm whale. All of the family members take turns watching over the little ones. Sometimes the two little ones play together at the surface while both moms are down and their aunt Quasimodo, or great-aunt Fingers, or half-brother Scar will watch over them from a distance.
Pinchy, Tweak, Fingers, Quasimodo, Scar, Mysterio, and Enigma are the members of a family I have nicknamed “The Group of Seven,” partly because a little Canadian art history never hurt anyone, but mostly because when I met them in 2005 there were seven whales in the family.
The Group of Seven is probably the best studied family of sperm whales in the world. They have shared with me all the minutia of living as a family of whales. All of these whale families have known each other for decades simply because they live in the same neighbourhood. There is a whole whale society out there in the deep that I am only beginning to understand.
We have put a man on the moon and a robot on mars, but the deepest part of the ocean in which the sperm whales have made their home is still mostly a mystery. These sperm whale families I have been working with off of the island of Dominica are like ambassadors from a deep ocean nation educating us about their way of life in a part of the ocean that is difficult for us to even explore.
Their world of sound is hard for us to understand because we rely so heavily on our ability to see. No matter how much noise we pump in, plastic we dump in, or chemical toxins we leach into the ocean; and no matter how many fish we harvest, ports we dredge, and oil we drill, to most people, the oceans still look the same from above the surface.
The truth is that the oceans have changed dramatically since Mysterio was born. They are warmer, more acidified, and more clogged with waste.
By learning from these families and sharing their stories, I hope to motivate others to ensure that today’s calves, like Enigma and Tweak, can raise their calves in a healthy ocean.
Thanks, Shane! For more information on Shane and The Dominica Sperm Whale Project, visit their website, find them on Facebook, or follow the project on Twitter @DomWhale
