May 23, 2007
Killer Whale Facts
- Orcas, also known as Killer Whales, are members of the dolphin family and are the highest predators in the food chain
- Orcas are highly intelligent mammals that live in matriarchal units comprised of a mother and one or more of her offspring, which congregate into larger social groups known as pods
- Biologists classify orcas in the Northeast Pacific Ocean into three morphologically, genetically, geographically and culturally distinct groups: resident, transient, and offshore orcas
- Resident orcas feed solely on fish, particularly salmon, while transient orcas eat marine mammals, such as seals
- Orcas are an integral part of the Pacific Ocean ecosystem and are an indictor species – whose health is an indicator for the overall ecological health of the marine environment
Southern Resident Orca Population
- The Southern Resident Orca population lives in the waters off the coast of southern British Columbia and northern Washington State
- Their range stretches from Puget Sound in the south, through the San Juan and Gulf Islands, and up Georgia Strait about mid-way up Vancouver Island
- Between 1993-2003, the Southern Resident Orca population fell by about 20%. With a few calves born in recent years, the population is currently approximately 87 individuals
- The Southern Residents are biologically and culturally distinct and have a unique acoustic repertoire and language, and do not interact with the Northern Residents
Threats to Killer Whales
- The Southern Resident Orcas face a number of serious environmental threats, including declining salmon stocks, increased boat traffic and toxic contamination from bioaccumulative chemicals such as PCBs
- Peer-reviewed scientific studies show that British Columbia’s resident and transient orcas are among the most contaminated marine mammals in the world
DND Proposes Re-Write of Sonar Discussion in Recovery Strategy
- In May 2007, Department of National Defence (DND) proposed revisions to scientists’ Killer Whale Recovery Strategy regarding military sonar testing in critical killer whale habitat
- DND has stated that the Canadian and American military vessels operating in Canadian waters should not be bound to any new regulations restricting sonar
- In October 2004, the European Parliament called on its member statues to stop deploying high-intensity sonar until further research can determine what harm it inflicts on marine life.
- DND has requested that this fact be removed from the scientists’ Recovery Strategy.
Military Sonar Testing
- DND conducts military sonar testing near Nanoose Bay in Georgia Strait, and off the west coast of Vancouver Island – activities that can be heard even 100 miles away
- Much of this testing involves joint operations with the US Navy.
- Military sonar can generate very loud sounds well above 160 dB, at which marine mammals may be harassed. At 180 dB, sonar generated sounds may cause physical injury in whales. Yet some mid-frequency sonar systems used by navies are louder than 235 dB.
- High-intensity underwater noise is accepted to disrupt marine mammal behaviour and can cause physical injury to marine animals.
- One way in which military sonar is thought to harm whales is by causing large emboli – or bubbles – in their organ tissues. This can involve internal bleeding in their brains and ears.
- Other effects to whales and fish include disrupting their ability to follow migration routes or to communicate. Naval sonar has been shown to disrupt killer whales’ feeding.
Sonar and Whale Strandings
- The International Whaling Commission has concluded that scientific evidence linking sonar to a series of recent whale strandings appears overwhelming.
- In May 2003, approximately 11 harbour porpoises beached themselves along Haro Strait in Washington State, as the USS Shoup tested its mid-frequency sonar system in the area. Acoustic trauma was a possible contributory factor in some of the porpoises’ deaths.
- DND has requested that the Recovery Team rewrite its discussion of this incident to better reflect the discredited internal US Navy investigation
- In July 2004, approximately 200 melon-headed whales crowded into shallow Hanalei Bay in Hawaii during a large naval sonar exercise, and had to be rescued.
- In January 2005, approximately 35 whales of three different species stranded on the Outer Banks of North Carolina as US Navy conducted sonar exercises offshore.
Canadian Recovery Strategy Delayed
- In November 2001, the Southern Residents were listed as Endangered in Canada by the Committee on the Status of Endangered Wildlife (COSEWIC), the federal scientific body established to evaluate the status of species throughout Canada
- Canada’s Species At Risk Act (SARA) came fully into legal force on June 1, 2004
- The Resident Killer Whale Recovery Team finished its Recovery Strategy in May 2006 – a science-based plan that identifies an endangered species’ needs, critical habitat, threats, and a broad conservation strategy to address those threats
- Although SARA mandates that the final Recovery Strategy be published by June 1, 2006, DFO has long delayed releasing the Recovery Strategy on the SARA Public Registry.