Only days before the cinematic release of a documentary about Luna - the killer whale that captivated the public before its death in Nootka Sound in 2006 - biologists are coming to terms with the loss of seven whales from the salmon-dependent southern resident population, including Luna's mother and younger brother.
"It's significant, a serious situation," Lance Barrett-Lennard, a killer whale scientist at the Vancouver Aquarium, said in an interview Tuesday. "But I don't think it's the death knell. It's a wake-up call to think about the fate of salmon stocks and the way we run our fisheries."
A total of seven killer whales are thought to have died since last fall, reducing the population of endangered southern residents to just 83 in three pods. That's up from 71 in 1973, but down from 100 in 1996.
Two of the seven were old females past their average life expectancy - K7, Lummi, estimated to be 98, and L21, Ankh, age 58.
Two others were newborn calves - L111 and J43 - thought to have a 50-per-cent chance of survival.
Most troubling for scientists is the loss of the remaining three, especially two breeding females - Luna's mother, L67, known as Splash, age 33, and J11, Blossom, about 36.
"This is of concern," said John Ford, a whale researcher with the federal fisheries department in Nanaimo. "Those two females were in the prime of their reproductive years. They normally have high survival."
Luna's younger brother, six-year-old L101, Aurora, is also thought to be dead.
Luna was an orphaned member of the southern residents who turned up in Nootka Sound on the west coast of Vancouver Island and adopted boaters as his new family. After years of controversy over what should be done with Luna, the six-year-old male whale died in a collision with a tug's propeller.
Declining runs of chinook salmon, the favourite prey of resident killer whales, are thought to be playing a role in the whales' decline in the shared waters of the Strait of Georgia and Washington's Puget Sound.
As the southern residents decline, they are also at increased risk from inbreeding, oil spills and contaminants such as PCBs, ship noise and collisions, and whale watchers.
Ford noted that not all the news is bad: the latest census suggests the population of threatened northern resident killer whales has increased to about 250 animals from 120 in the early 1970s.
Saving Luna is an award-winning documentary directed by Suzanne Chisholm and Michael Parfit that is scheduled to open in Vancouver Dec. 5 at the Ridge Theatre, in Victoria on Jan. 16 and Toronto on Jan. 23.
A special screening will be held this Sunday, 10 a.m., at the Park Theatre, 3440 Cambie, to conclude The Vancouver Sun Film Series, with both directors as well as Barrett-Lennard in attendance to answer audience questions.
zaterdag 29 november 2008
donderdag 20 november 2008
Dog's nose for whale poop big help to B.C. orca researchers
Killer whale poop, sniffed out by a specially trained, excitable Labrador-cross, is showing that endangered southern resident orcas may not be finding enough to eat.
Researchers from the University of Washington's Center for Conservation Biology have just completed their third season testing whale scat around Juan de Fuca Strait and Puget Sound, looking for clues to why the population is shrinking.
"What pops out right away is that there are lower thyroid hormone levels in the years when there are higher rates of mortality," said Katherine Ayres, a graduate student who is working on the whale project with Sam Wasser, director of the centre.
"This suggests they are experiencing nutritional deficits. We can tell, according to the thyroid hormone, they are not doing as well this year as the year before," Ayres said.
This year seven members of the three southern resident pods have died, including two breeding age females, bringing the population to 83. The recent population high was 97 in 1996.
"Alarm bells are going off. It is pretty devastating for such a small population," Ayres said.
Lack of chinook salmon - the food favoured by resident killer whales - noise from marine traffic and toxins have been identified in previous studies as probable causes of the decline.
If funding allows, the Center for Conservation Biology hopes to expand its research to look at toxins and the effects of boat traffic.
"With these studies we can start giving answers before the animals die and we can take mitigation measures," Ayres said.
The slimy, green excrement is found by Tucker, a four-year-old Lab who stands on the bow of the center's research boat and goes into paroxysms of excitement when he smells whale poop, which means it can be scooped by researchers.
Last year, researchers tried following the pods more closely and scooping poop without Tucker's help, but it was found everything worked better with a dog.
"It was more a human learning curve than a dog learning curve," said Ayres, who believes Tucker is incredibly good at his job.
Program co-ordinator Heath Smith identified Tucker's talents. Tucker had already failed as a house pet and been rejected for police work.
"I went to look at him and I knew he would be good at scat work. We haven't had a dog that has caught on quicker. He just knew this was what he wanted to do."
Before the whale project started, the centre was using dogs to sniff out scat from other animals, from grizzly bears to giant armadillos. Samples are used to test stress, exposure to toxins and diet.
When Tucker came to work for the centre it was not known he would be put on the whale project. But, then it was discovered he was afraid of water.
"We wanted a dog that was not so focused on getting in the water," Smith said.
"He still doesn't like it at all. If he does jump overboard we know there's scat in the water," he said.
Tucker is supposed to be pure Lab, but, with brindle feet and a huge head, Smith doubts his pedigreed. "He's adorable. He's part of the family," he said.
Researchers from the University of Washington's Center for Conservation Biology have just completed their third season testing whale scat around Juan de Fuca Strait and Puget Sound, looking for clues to why the population is shrinking.
"What pops out right away is that there are lower thyroid hormone levels in the years when there are higher rates of mortality," said Katherine Ayres, a graduate student who is working on the whale project with Sam Wasser, director of the centre.
"This suggests they are experiencing nutritional deficits. We can tell, according to the thyroid hormone, they are not doing as well this year as the year before," Ayres said.
This year seven members of the three southern resident pods have died, including two breeding age females, bringing the population to 83. The recent population high was 97 in 1996.
"Alarm bells are going off. It is pretty devastating for such a small population," Ayres said.
Lack of chinook salmon - the food favoured by resident killer whales - noise from marine traffic and toxins have been identified in previous studies as probable causes of the decline.
If funding allows, the Center for Conservation Biology hopes to expand its research to look at toxins and the effects of boat traffic.
"With these studies we can start giving answers before the animals die and we can take mitigation measures," Ayres said.
The slimy, green excrement is found by Tucker, a four-year-old Lab who stands on the bow of the center's research boat and goes into paroxysms of excitement when he smells whale poop, which means it can be scooped by researchers.
Last year, researchers tried following the pods more closely and scooping poop without Tucker's help, but it was found everything worked better with a dog.
"It was more a human learning curve than a dog learning curve," said Ayres, who believes Tucker is incredibly good at his job.
Program co-ordinator Heath Smith identified Tucker's talents. Tucker had already failed as a house pet and been rejected for police work.
"I went to look at him and I knew he would be good at scat work. We haven't had a dog that has caught on quicker. He just knew this was what he wanted to do."
Before the whale project started, the centre was using dogs to sniff out scat from other animals, from grizzly bears to giant armadillos. Samples are used to test stress, exposure to toxins and diet.
When Tucker came to work for the centre it was not known he would be put on the whale project. But, then it was discovered he was afraid of water.
"We wanted a dog that was not so focused on getting in the water," Smith said.
"He still doesn't like it at all. If he does jump overboard we know there's scat in the water," he said.
Tucker is supposed to be pure Lab, but, with brindle feet and a huge head, Smith doubts his pedigreed. "He's adorable. He's part of the family," he said.
Deadly bacteria found on orcas
Researchers studying droplets emitted from orca blow holes have found drug-resistant bacteria.
They could be a sign of pollution and a risk to the killer whale population in Puget Sound, which is apparently in decline.
The Kitsap Sun says the independent research by biologist David Bain and veterinarian Pete Schroeder was presented at a Tuesday meeting in Friday Harbor on orca health.
Schroeder says the bacteria may come from human sources such as untreated sewage or stormwater.
Seven Puget Sound orcas are missing and presumed dead, bringing the population to 83, the fewest in five years.
They could be a sign of pollution and a risk to the killer whale population in Puget Sound, which is apparently in decline.
The Kitsap Sun says the independent research by biologist David Bain and veterinarian Pete Schroeder was presented at a Tuesday meeting in Friday Harbor on orca health.
Schroeder says the bacteria may come from human sources such as untreated sewage or stormwater.
Seven Puget Sound orcas are missing and presumed dead, bringing the population to 83, the fewest in five years.
woensdag 12 november 2008
Sounds Like My Favorite Fish
Some of the killer whales off the coast of Washington state are picky eaters, preferring Chinook salmon even though the coho and sockeye varieties are much more plentiful. Researchers report that the whales seem to be able to tell the three species apart by the sonar echoes bouncing off their swim bladders. The discovery should help efforts to protect these intelligent mammals and maybe someday lead to the design of new devices that could identify individual fish species remotely.
Sorting the three salmon species isn't easy even after you've landed them, but certain pods of Orcinus orca can discriminate between individual fish as they move around the dark and turbulent waters of the southern Puget Sound. Researchers suspected that the whales prefer Chinook salmon because they carry more fat and therefore provide more calories. "The whales get more bang for the bite," says marine ecologist John Horne of the University of Washington, Seattle. Horne and colleagues understood generally how the whales found their prey: by reading the echoes from their built-in sonar. But no one knew what acoustic characteristics could help the orcas tell one salmon species from another.
So Horne and colleagues bounced digital replicas of the orcas' clicks off live but immobilized specimens of the three salmon species. Their analysis showed that one characteristic--the structure of the echoing sound waves--differed among the coho, sockeye, and Chinook salmon. As bioacoustician and team member Whitlow Au of the University of Hawaii, Honolulu, reported Tuesday at a meeting of the Acoustical Society of America in Miami, Florida, further study showed that the salmon swim bladders vary considerably in size. The Chinook's bladder is only half as large as those of the other two species. That's important, Horne explains, because the swim bladder is responsible for 90% of the reflected sound energy. "It acts almost like a wall," he says. The team concluded that the echoes from the three species differ enough for orcas to detect and discriminate single Chinook at distances of 100 meters or more. The remaining question, Horne says, is how killer whales process these signals. But even if that remains a mystery, the research could lead to the development of sonar devices or analytical techniques that could classify and identify individual fish species, making it easier to take a population census. "That would be the Holy Grail of fisheries acoustics," he says.
The findings are important, says killer whale biologist John Ford of the Pacific Biological Station in Nanaimo, Canada. "The question we've been stewing on for some time is how the whales differentiate among the salmon," he says. The research answers that question, but it poses another issue, Ford explains. The whales have evolved to feed on the Chinook, whose population is in decline, so it is essential that their access remain unrestricted. These findings mean we need to determine how much "underwater vessel noise might interfere with their ability to detect salmon in their critical habitats," he says.
Sorting the three salmon species isn't easy even after you've landed them, but certain pods of Orcinus orca can discriminate between individual fish as they move around the dark and turbulent waters of the southern Puget Sound. Researchers suspected that the whales prefer Chinook salmon because they carry more fat and therefore provide more calories. "The whales get more bang for the bite," says marine ecologist John Horne of the University of Washington, Seattle. Horne and colleagues understood generally how the whales found their prey: by reading the echoes from their built-in sonar. But no one knew what acoustic characteristics could help the orcas tell one salmon species from another.
So Horne and colleagues bounced digital replicas of the orcas' clicks off live but immobilized specimens of the three salmon species. Their analysis showed that one characteristic--the structure of the echoing sound waves--differed among the coho, sockeye, and Chinook salmon. As bioacoustician and team member Whitlow Au of the University of Hawaii, Honolulu, reported Tuesday at a meeting of the Acoustical Society of America in Miami, Florida, further study showed that the salmon swim bladders vary considerably in size. The Chinook's bladder is only half as large as those of the other two species. That's important, Horne explains, because the swim bladder is responsible for 90% of the reflected sound energy. "It acts almost like a wall," he says. The team concluded that the echoes from the three species differ enough for orcas to detect and discriminate single Chinook at distances of 100 meters or more. The remaining question, Horne says, is how killer whales process these signals. But even if that remains a mystery, the research could lead to the development of sonar devices or analytical techniques that could classify and identify individual fish species, making it easier to take a population census. "That would be the Holy Grail of fisheries acoustics," he says.
The findings are important, says killer whale biologist John Ford of the Pacific Biological Station in Nanaimo, Canada. "The question we've been stewing on for some time is how the whales differentiate among the salmon," he says. The research answers that question, but it poses another issue, Ford explains. The whales have evolved to feed on the Chinook, whose population is in decline, so it is essential that their access remain unrestricted. These findings mean we need to determine how much "underwater vessel noise might interfere with their ability to detect salmon in their critical habitats," he says.
maandag 10 november 2008
Kite surfer's orca encounter
A chance encounter with a pod of orca whales provided a special thrill for Raglan kite surfer Matt Taggart last weekend.
A normal Saturday afternoon turned into a memorable moment for Mr Taggart when a pod of five or six orcas, including a mother and calf, came close to shore in search of stingray.
"A couple of the local guys, Olly and Keith, noticed them and said `come on, get back out there' ... to be honest I was bricking it. I know them as killer whales and I thought no way am I going out there with killer whales," Mr Taggart said.
"But I went out and was taking it quite carefully when the mother popped up right in front of me.
"I never thought I would ever do that ... it was crazily intense. She was literally metres away."
Mr Taggart was out on the water with the orcas for about 15 minutes, but lack of wind meant it was difficult to stay with them.
"I was just trying to enjoy the moment. I was absolutely blown away.
"They came through so quickly ... I guess I was fortunate to be there at the right moment."
Locals had told him orcas came in close to shore to flush out stingray before circling and eating them.
"I'm chuffed. I'm stoked I got out there. It would have been easy not to, but I'm glad I did."
Originally from England, Mr Taggart has made his home in Raglan since January after marrying a Kiwi girl.
He is the manager of Raglan-based Ozone Kites/Kitesurf Ltd.
"We make and design kites of all forms - land, snow, water, for families.
"We're setting up our whole base here, I love it. For kiting it is amazing."
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