What's happening with harbour porpoises?
While harbour porpoises may not win any awards for being the most exciting species to observe in the wild, they are still one of the most abundant cetaceans on our coastline. Unfortunately, harbour porpoises in BC have been overlooked by many researchers and as a result, we know very little about them. Thanks to many people who report sightings to the BC Cetacean Sightings Network, we have a good idea about where harbour porpoises are found and concentrated; however, we don’t know if mixing of individuals goes on between these concentrated groups.
Carla Crossman, a Masters Student at the University of British Columbia (UBC) who is funded by the B.C. Wild Killer Whale Adoption Program, is collaborating with researchers at the Vancouver Aquarium to determine the genetic make-up of harbour porpoise. Carla is using DNA extracted from skin samples from harbour porpoises that strand along the B.C. coast to compare the genetic codes of individuals. If individuals are closely related to each other, they will have a very similar genetic code, while individuals that are distantly related will have different genetic codes. Once Carla has finished her analysis she will compare if individuals that were found close to each other are more closely related than individuals found far apart.
Some of Carla’s results to date were very surprising (and exciting)! We already knew there are harbour porpoise/Dall’s porpoise hybrids in southern B.C., but it appears there are many more than we originally believed. A few known harbour porpoise samples had Dall’s porpoise DNA, and at least one Dall’s porpoise had harbour porpoise DNA! Unlike some of the hybrids seen in the wild that can be rather distinct, these hybrids looked just like one of the parental species. Without the genetic data, we would have no way of knowing these were hybrids. Until now we thought all hybrids had harbour porpoise fathers and Dall’s porpoise mothers, but there is now evidence for crosses in both directions!
Carla’s research is helping fill in the knowledge gaps and will become very useful for management of the threatened populations of harbour porpoise in BC.
Photo: Susan Mackay
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In the News....
A young whale is lost in the southern residents!
On February 11, 2012 sad news broke of a young killer whale found washed up on the shore just north of Long Beach, Washington. The young whale was identified as L112, also known as Sooke, a three year old female from the endangered Southern Resident killer whale population. L112 was part of the L4 matriline and the second surviving calf of Surprise (L86). The following morning, Feb 12th, veterinarians and researchers working with the Northwest Marine Mammal Stranding Network in the US examined L112’s body, and although her cause of death is still undetermined, the researchers noted major trauma injuries surrounding her head and chest. Further internal examination showed damage to
her internal organs, her ear bones were dislodged and a loss of brain matter – injuries that suggest cause of death could have been massive impact trauma from an explosion.
L112’s injuries may be related to Canadian or American Navy testing in the waters of Juan de Fuca Strait or the southern Washington to northern Oregon coast. This incident underscores the need for stronger protection of the endangered resident killer whales in their critical habitat.
Photo: Cascadia Research
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Case Closed - The courts ruled that DFO must protect killer whale critical habitat!
Court rulings have dictated that the federal government must protect critical habitat for the endangered Southern Resident Killer Whales and for the threatened Northern Resident Killer Whales!
In 2009 Ecojustice, an environmental law firm representing nine environmental groups, took DFO to court for failing to meet its responsibilities under the Species at Risk Act (SARA). Under SARA a recovery strategy must be developed for any species designated as endangered or threatened. After a recovery strategy was completed for killer whales that identified the species’ critical habitat and principal threats to its long-term survival, the Minister of Fisheries and Oceans issued a “protection statement” claiming that existing laws and guidelines provided adequate protection. Ecojustice argued that existing laws were insufficient to provide legal protection of critical habitat, as required by the SARA, and that the minister should have issued a “protection order”.
In December of 2010 the judge agreed with the environmental groups and ruled that the Minister’s actions had been unlawful. DFO appealed one part of the judgment and lost in February. It was uncertain whether DFO would appeal again to a higher court, however, the deadline of April 10th passed without an appeal and the case is closed! This ruling affirms the legal responsibility of the Federal Government to protect the attributes of critical habitat that make it suitable for killer whales, including availability of prey and low levels of acoustic disturbance and chemical contamination.
Results of this case are exciting – not only for the resident killer whales, but also all the other species listed under SARA. A new precedent has now been set and habitat for all SARA-listed species will have to be protected by the Federal Government.
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