MATRIARCH COMPETITION
ORCAS
Agnes Rose, LVI
Pods of orca whales inhabit every major ocean, with each family able to survive from the help of an experienced hunter, the grandmother. Grandmother whales can live 80 years or longer, whilst most males generally only live until the age of 30. After various studies, we have learnt a great deal about a specific population of these whales, known as the Southern Residents.
Each carf is born into a matriline (the mother’s family), where they spend most of their life hunting, eating, playing and even communicating with each other through their own specific calls. A young whale also shares a dialect with neighbouring families meaning they can socialise regularly. Once a female reaches the age of 15 these interactions become opportunities to mate with the neighbours’ young males. She and her calves return to the matriline and continue their life together, whilst the male remains with his own mother. This mother then gives birth on average every six years until the age of 40 when she enters menopause. This is fascinating as it is only known for some species of whales as well as humans for females to continue to live for years after they stop reproducing.
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Grandmothers then lead the pod and begin to hunt for salmon; during this time she shows her young where to find the most fertile fishing ground as well as sharing 90% of the salmon she catches with the pod. The grandmother’s expertise can be the difference between life and death for these families. Because most of the pod are daughters or grandchildren of these elder female whales, they focus the later portion of their lives on benefiting the whole pod, allowing younger females to concentrate on reproducing. These populations of Southern Resident Killer Whales are critically endangered due to the rapidly declining salmon populations. We desperately need to invest in restoring the salmon populations to prevent extinctions of these impressive creatures.
