When vessels slow down, underwater noise is reduced, and so does the impact on whales, according to a Vessel Slowdown Trial led by the Port of Vancouver’s Enhancing Cetacean Habitat and Observation (ECHO) Program.
The ECHO Program initiated the first-of-its-kind voluntary Vessel Slowdown Trial through Haro Strait last summer, to study the relationship between slower ship speed, underwater noise levels, and effects on the endangered southern resident killer whales in one of their key feeding areas.
During the trial period, operators of cargo ships transiting a corridor of about 16 nautical miles were asked to navigate over listening stations (hydrophones) and reduce their speed to 11 knots, when it was feasible and safe to do so. More than 60 marine shipping industry organizations took part in the trial, allowing enough data to be collected.
Results from the trial demonstrate that reducing vessel speeds is an effective way of reducing the underwater noise generated by the vessel and reducing total underwater noise in nearby habitats, which can in turn benefit the behaviour and feeding success of the southern resident killer whale. Whales use sound to locate prey and ship noise can interfere with their ability to do that.
In line with the government’s efforts to save whales populations, the port authority and its ECHO Program partners will support an industry-led voluntary slowdown initiative this summer also in Haro Strait, which is being spearheaded by the Chamber of Shipping, CLIA – North West & Canada and the Shipping Federation of Canada.
This initiative will test the level of industry participation when vessel slowdown speed is optimized based on vessel type, and when the slow down comes into effect when whales are present in the area.
Robin Silvester, President and CEO at the Vancouver Fraser Port Authority, said:
Based on what we learned from last year’s trial and with ongoing input from the marine industry, we were able to better determine optimal slow down speeds that will both reduce underwater noise and ensure cargo can get to its destination on time. This is another important step that the marine industry is taking to support the recovery of the endangered killer whale population, and we look forward to recording even higher vessel participation rates and associated environmental benefits this summer.
Due to the changing migratory habits of the North Atlantic right whale and their increased presence in the Gulf of St. Lawrence, the Government of Canada announced earlier in June seasonal speed restrictions in a specified zone, from 28 April to 15 November 2018. These restrictions are a combination of static zone and dynamic speed reduction sectors.