The Fisheries Department says Carl Peterson's conviction is the first under the Species at Risk Act, which prohibits anyone from harassing a member of a wildlife species that's listed as endangered or threatened.
The charges were laid after an incident in August 2010 when Fisheries officers on patrol in the waters around Quadra Island, near Campbell River, observed a recreational power boat repeatedly accelerating towards the whales.
A Fisheries news release says Peterson's boat eventually powered up to within 25 metres of the animals, contrary to long-established whale-watching guidelines that require a minimum distance of 100 metres.
Provincial court heard scientific evidence suggests close approaches to orcas by boats can disrupt their normal behaviour and if frequent, can cause long-term harm to the population.
Peterson will be sentenced later in the fall and could face a maximum fine of $250,000.
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