Can you feel the noise?

This spectogram visually shows the sound of a vessel approaching and gradually moving away from the hydrophone installed at SG_aan K_inghlas Acoustic data courtesy of John Ford, DFO. Image courtesy of JASCO Applied Sciences

By Molly Clarkson — SGaan Kinghlas, Supernatural Being Looking Outwards is an enormous seamount located 180-kilometres off the west coast of Haida Gwaii. The 3100-metre mountain is submerged beneath the waves of the Pacific Ocean and supports an abundance of marine life. Rockfish, sablefish, crab, sea anemones, squid, octopi, sponges, corals and sea stars thrive at SGaan Kinghlas, which in turn attract large marine mammals such as stellar sea lions, orca, humpback and sperm whales.

The Haida Nation designated SGaan Kinghlas as a Haida Marine Protected Area in 1997 and in 2008 the Nation and Canada jointly designated SGaan Kinghlas Canada’s seventh Marine Protected Area (MPA).The seamount is the first MPA in Canada to be co-managed by a First Nation and a Crown government. Currently, the Management Board for the MPA – consisting of two representatives from the Haida Nation and the Department of Fisheries and Oceans – is developing a plan for the management of the MPA. New research into ocean noise is providing information that will help the Board protect the beings that live around the seamount and manage human behaviour.

Research has shown that ocean noise can negatively impact marine animals, particularly marine mammals like whales, which depend on sound for communication, foraging and navigation. These impacts can be behavioural, such as a temporary halt to singing, changes in surfacing, heading and diving patterns, and the abandonment of important habitat. They can also be acoustic, like a reduced ability to forage or locate mates, and physiological, such as diminished or loss of hearing and high stress. Fish and invertebrates can also be negatively affected by ocean noise.

Marine traffic is the most significant source of human generated noise in the oceans surrounding SGaan Kinghlas. The MPA is located along the route of oil tankers carrying oil from Prudhoe Bay and Valdez, Alaska, southwards to ports in the United States. A Tanker Exclusion Zone off Canada’s west coast was established in 1988 in order to provide some protection to sensitive coastal ecosystems in the event of an oil or hazardous cargo spill. However, the summit of the seamount is located between 18-36 kilometres west of the Tanker Exclusion Zone and tankers continue to transit nearby waters. Marine traffic in the area is also expected to increase due to longer ice-free arctic navigation routes and planned port expansion along the west coast.

In order to evaluate the potential ecological impacts posed by marine traffic the Board is working with digital mapping expert Rosaline Canessa, director of the Coastal and Ocean Resources Analysis Lab (CORAL) at the University of Victoria. Dr. Canessa’s interest in the seamount dates back to 2003, when she contributed to an ecosystem overview of the area. In 2011 she was invited to participate on the SGaan Kinghlas MPA advisory committee, a multi-stakeholder group that provides advice to the Management Board regarding planning and management of the MPA. So when a research opportunity came up to study noise generated by marine traffic, Dr. Canessa suggested SGaan Kinghlasas a valuable case study. The Salish Sea and Sachs Harbor area in the Northwest Territories were also selected for the multi-year ocean noise research project.

The goal of the project is simple: “Ultimately, we want to know how much noise is being generated from [human] sources and then what species are there that could be susceptible to impact from that noise,” said Dr. Canessa.

The research, however, is anything but simple. Dr. Canessa, assisted by Casey Hilliard of Dalhousie University and UVIC PhD candidate Ainsley Allen, have been busy over the past year analyzing Automatic Identification System (AIS) vessel traffic data and noise in and around the MPA. Results so far suggest that there is a significant amount of activity, mostly from fishing, cargo and tanker vessels.

They found that the majority of tankers travel to the west and beyond SGaan Kinghlas’ boundaries, in 2012 four tankers transited through the MPA. Cargo vessels tend to travel to the east of the boundary, while fishing vessels track back and forth across the MPA.

While the data suggests that more vessels transit near or within the MPA in the winter than in the summer months, the research team’s early findings suggest that the amount of noise is much higher during the summer months, when good weather and calm seas reduce the amount of natural noise in the ocean.

The implication of these findings will be the next focus of the team’s research. The project is expected to wrap up in March 2017, at which point Dr. Canessa will be working with the MPA Management Board to apply her research to management and monitoring practices.

DID YOU KNOW?

In April, 2014 the International Maritime Organization adopted guidelines for the reduction of underwater noise from commercial shipping. These include reducing underwater noise through propulsion and hull design, and better operating procedures, such as going slower, which reduces noise. However, these guidelines are non-binding, and have yet to be incorporated into national legislation or adopted by the shipping industry in Canada.