According to
Birds Canada, 20 years of BC Coastal Waterbird Surveys show a new problem in the Salish Sea. First it was mainly fish-eating waterbirds that went into decline. Now it is benthivores that are declining most. These birds forage on the shallow bottom of the sea. Only about 5% of BC's ocean area is less than 50m deep, and this is also the most diverse and productive marine ecosystem where commercial anchorages are expanding. See:
Article,
Original Study