Recreational activity a major pollutant on Canadian coast of Pacific Ocean

The study -- published in the August edition of the journal Applied Geography, with University of Calgary associate professor in geography Stefania Bertazzon as lead author -- provides a geospatial analysis of oil discharges in the Canadian Pacific Ocean.

The findings show that a large portion of oil discharge within these waters stems from recreational activities, passenger traffic and fisheries. According to this scientific analysis -- conducted on oil spills observed by the National Aerial Surveillance Program with the use of remote sensing devices -- these sources are polluting the ocean along the British Columbia coast more than oil tankers and commercial cargo ships.

"Cargo ships and oil tankers are much more regulated with portside inspections and they have to meet certain standards," explains Bertazzon. "They're very aware of this surveillance and this is probably why our analysis suggests that they are responsible for a smaller portion of detected oil discharges. They have to be more careful."

Bertazzon adds: "We're not saying that cargo ships and oil tankers are not polluting. What we are saying is that they are not the only source of pollution in the Canadian Pacific Ocean."

Bertazzon and her co-authors explain that fuel docks for recreational and fishing vessels can be problematic. "We know that there's a lot of oil discharge in these fuel docks, which is largely uncontrolled," she says.

"One thing that happens in these marinas is there's a lot of old boats which have been sitting there for years slowly leaking into the ocean. These are not huge spills. It's a relatively small discharge. But there's a lot of these derelict vessels and together they make for a large source of pollution."

While there's no denying the impact of large-scale oil industry disasters such as the Gulf of Mexico spill in 2010, Bertazzon argues that the oil discharges related to maritime activities are even more devastating to marine ecosystems in the long run.

"There is scientific evidence to show that these day to day activities have a larger impact on the wild life and the marine ecosystem than those accidents that are huge, but limited in space and time," says Bertazzon. "What we're talking about happens every day, all along the coast. The impact is longer term and over a larger spatial extent."