There are several distinct populations of orca in the waters of British Columbia, and the pods most common to the Telegraph Cove area belong to the Northern Residents. These orcas are specialized in eating chinook salmon, nearly to the exclusion of all other potential foods and are an iconic part of the landscape of northern Vancouver Island.
They travel in pods between a pair to several dozen and like all orca, have a matriarchal society in which the sons stay with their mothers most of their life (according to a book we read last year, sons may spend up to 65% of their life within a body length of their mother). Since they must constantly come up for air, they can only let half of their brain sleep at atime, so they are commonly found in a resting formation where they travel along slowly and breathe frequently.
When fully awake and active, their behaviour can be quite varied and exciting with all manner of spy hops (below), tail slaps, pectoral fin waves, breaches and vocalization. People only began seriously studying these animals in the 50s and the volume of information yet to be learned is huge, but with such striking and charismatic behaviour there should be no shortage of excited researchers and observers.
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