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Social Structure

Before the 1970's, virtually nothing was known about orca social structure. As a result of the pioneering photo identification study undertaken by Dr. Michael Bigg of the Pacific Biological Station at Nanaimo which began in 1972, each of the individual orcas found along the coasts of British Columbia and Washington State was identified and assigned an alphanumerical identification ("ID"). It became apparent to Dr. Bigg and his associates that the orca population was not as large as first assumed. Individuals live in small stable family units within a larger community. Since then, our understanding of the resident orca social structure has continued to be refined and at present is described in the following manner:

Social Unit ID

individual orca A33

the matriline (a mother and her offspring) A12

the pod (closely related matrilines) A01

the clan (those pods with a common acoustic tradition) A

the community (the clans which share a common geographic range) Northern Resident

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