News Category: Science
Canadian scientists lead the way in analysis of Martian atmosphere
Team will develop spectrometer to use in search for signs of life on Red Planet
By Mike Barber – Vancouver Sun – August 3, 2010
A Canadian team will share a lead role in creating an instrument to analyze the levels of methane and oxygen in Mars’s atmosphere, potentially uncovering signs of life on the red planet.
The Canadian Space Agency announced Monday a team of Canadian scientists will develop the Mars Atmospheric Trace Molecule Occultation Spectrometer.
It is an extremely sensitive device that will orbit Mars and document the planet’s chemical makeup, said Victoria Hipkin, a planetary scientist with the agency and the project’s co-leader.
The spectrometer will be placed aboard the ExoMars Trace Gas Orbiter, a joint project of NASA and the European Space Agency scheduled to launch in 2016.
If successful, “it would set a very clear pathway for future Mars exploration,” Hipkin said. “It’s a very ambitious mission.”
The spectrometer has its roots in another Canadian endeavour, a satellite measuring trace amounts of gas on Earth that has yielded discoveries on ozone depletion and air quality since its launch in 2003, Hipkin said.
“We’re now applying this amazingly sensitive instrument to the Mars atmosphere to look for signs of activity,” she said. “This is an area in which Canada is currently leading the world.”
The spectrometer will search primarily for methane, which Hipkin called “a potential signature of biology on Mars.”
On Earth, both methane and oxygen are primarily produced by life—methane from algae and the digestive tracts of animals, and oxygen from plants.
“Together, they provide an amazing signature for anyone looking at Earth a long way away to say that there must be active biology on this planet, because those two gases will react together,” Hipkin explained.
The spectrometer will be able to measure how much methane there is at different locations around Mars, and how it changes throughout the seasons.
Areas with higher concentrations would indicate regions on Mars’s surface ripe for further exploration.
“Trying to understand its atmospheric chemistry is a different kind of fundamental look that we’re taking at Mars that hasn’t been done before,” Hipkin said.
“The technique we’re applying to Mars now is the primary one we will use to understand the planets beyond our solar system.”
Canadian sounds alarm on wombat carnage Down Under
Beaver-sized marsupials are dying by the thousands as roadkill on highways around Sydney, ironically in areas identified as reserves
By Randy Boswell – Vancouver Sun – July 22, 2010, p. B3
A young Canadian scientist, who earned her academic spurs studying moose and porcupines in the Great White North, is now grabbing headlines Down Under for her efforts to protect Australia’s iconic wombat, the beaver-sized marsupials that are dying by the thousands as roadkill on highways around Sydney.
University of New South Wales wildlife biologist Erin Roger, an Ottawa native who also went to school in British Columbia and Nova Scotia, has raised alarms over the wombat carnage in southeast Australia, where about 3,000 of the creatures are killed annually by cars and trucks—often, ironically, in areas identified as wombat reserves.
“I am interested in how roads are an often overlooked threat and how we continue to build more and more roads with little regard for the kinds of habitat and species populations we are fragmenting,” Roger said in an interview. “I feel like people have this sense of inevitability when it comes to roadkill, whereas in most other situations that kind of loss of life would be otherwise very concerning.”
Her research, featured last week in the Sydney Morning Herald and on Australian radio, has highlighted the potential need for mitigation measures such as fencing along roadways and animal-crossing structures.
In the Herald article, the Canadian researcher perhaps risked a backlash from Australians by expressing her surprise at the “negative” attitudes many in the country hold toward commons species such as the wombat and kangaroo—treating “icons as pests,” she said.
“The conservation of wildlife populations living adjacent to roads is gaining international recognition as a worldwide concern,” Roger and two UNSW colleagues wrote recently in the journal Population Ecology.
Their study noted that road deaths are having a significant, species-wide impact and are a greater threat to some wombat subpopulations than either of the traditional threats to the animal—diseases such as mange or predation by the dingo and Tasmanian devil.
Ancient underwater ecosystems found off Newfoundland’s coast
By Giuseppe Valiante – Vancouver Sun – July 21, 2010, p. B1
A team of Canadian and Spanish scientists has discovered forms of marine life previously unknown to science, some of which are more than 1,000 years old and hold the secrets to ancient underwater ecosystems.
The Fisheries Department and scientists from three Canadian universities and the Spanish Institute of Oceanography are on a 20-day expedition, using a robot to take pictures and to grab samples of coral and sponges up to three kilometres deep in the waters off the coast of Newfoundland.
The team is studying 11 areas under protection of the North Atlantic Fisheries Organization (NAFO) that are, collectively, about 1½ times the size of Prince Edward Island.
These areas are important because they contain the “trees of the ocean,” says Ellen Kenchington, research scientist with the Fisheries Department, who is one of the leaders of the expedition.
The coral that grows in this area can be several metres tall and change the flow of water currents. It also gives shelter to fish and other organisms.
“It’s a similar function a tree would serve in the forest, cutting down wind, providing branches for birds. We have the same type of communities that take shelter down there,” she said.
These coral and sponges—which are extremely fragile—are essential in keeping the areas abundant with the marine life that is fished by many countries around the world, including Canada, the U.S., the European Union and Japan.
Kenchington’s team is assessing whether more of these areas need to be protected from fishing in order to keep stocks sustainable.
During the course of the research, Kenchington’s team says it has discovered at least two new species of coral and six sponges in international waters, thousands of metres down.
Black coral, in particular, cements itself to the bottom of the ocean and can live more than 1,000 years. The coral has the equivalent of growth rings that can be revealed when sectioning its skeleton.
Kenchington said scientists can potentially look at the coral’s chemical composition and determine the temperature of the water and other data from as far back as 1,000 years.
“That’s how we are able to say if there is warming or a change in climate direction,” she said. “In order to understand the present we need to put it into context.”
‘Cold’ genes linked to disease prevention
In the constant battle between humans and pathogens, a University of Victoria research team including Crystal L. Schmerk and Catharine M. Bosio is one step closer to finding a new defense against infection.
Properties of Arctic microbes may allow harmful bacteria to be killed at moderate temperatures
By Randy Boswell, Vancouver Sun – July 15, 2010
A team of Canadian scientists has exploited the heat-hating properties of several species of Arctic bacteria to develop potentially life-saving—and lucrative—methods of genetically re-engineering harmful germs for new vaccines and safer microbiology research labs.
The remarkable discovery, detailed in the latest edition of the Proceedings of the National Academy of Sciences, is described by the University of Victoria-led researchers as a possible breakthrough in preventing diseases such as tuberculosis and typhoid fever and in creating cheaper and more secure scientific facilities where risky bacteriological research is undertaken.
Among the Arctic microbes used in the B.C. team’s experiments is Colwellia psychrerythraea, a so-called “psychrophile” or a cold-loving bacterium that is known to leave a reddish tinge on the sea ice it sometimes inhabits in polar regions.
Another species used by the researchers, Shewanella frigidimarina, is described in the paper as coming from Arctic Ocean samples collected “near the northernmost point of Canada”—Ellesmere Island.
The scientists injected several “essential genes” from the cold-adapted organisms into more heat-loving, disease-causing germs, creating modified microbes that survived and reproduced in cooler conditions but quickly died at higher temperatures that would be found inside a human body or, in some cases, its warmer organs—such as the lungs.
Using the Arctic bacteria’s heat-sensitive traits to control when and where to trigger the deaths of harmful germs offers significant opportunities to develop new vaccines against various infectious diseases, the researchers state.
“Among the hundreds of psychrophilic bacterial species, there are undoubtedly numerous essential gene products that are inactivated at temperatures that are relevant to biotechnology applications,” the study states. “It is likely that a high proportion of newly found, temperature-sensitive essential genes could be used in any bacterium whenever there is a need to use heat to kill the bacterium at a moderate temperature.”
University of Victoria biochemist Francis Nano, one of five B.C. researchers who coauthored the study with a U.S. scientist, told Postmedia News on Wednesday that the team spent five years working on the project before hitting on the right combination of genetic traits to create viable organisms with a reliable, heat-triggered kill switch.
“People have been talking about using these cold-loving bacteria as sources of enzymes in laundry detergents that use cold water,” Nano said.
But the research team’s goal, he noted, is considerably more ambitious: To move the crucial traits of the Arctic bacteria “into some of the world’s most important pathogens” to combat fatal diseases around the world and to protect scientists from the “dangerous bacteria” they frequently handle in the name of medical research.
“The genes in our study fell apart between 33 and 37 degrees Celsius,” Nano stated in a summary of the study, “which means extraordinarily dangerous pathogens such as those that cause drug resistant staph infections, TB and even plague could be made inactive at body temperature and safe for vaccines and research.”
Nano said the team’s study has also illuminated the emerging importance of “bioprospecting” in the Arctic’s unique, organism-rich ecosystems, a field of scientific research and economic development in which Canada—despite its vast expanse of Arctic land and water—is falling behind more competitive polar nations.
He pointed to a 2008 UNsponsored report on Arctic bioprospecting that suggested Canada was not keeping up with countries such as the U.S., Russia and Norway in filing patents for biotechnology products derived from “Arctic genetic resources.”
Trent Ph.D. Study Disrupts Long-held Beliefs about Historic Grey Wolf Distribution in East N America
Dr. Linda Rutledge’s study of 16th century skull fragments suggests eastern wolves, not grey wolves, inhabited forests of eastern North America prior to arrival of European colonists
A research study conducted by Dr. Linda Rutledge, during her time at Trent University as a Ph.D. student in the Environmental & Life Sciences Graduate Program, and published this week in the journal Conservation Genetics, has the potential to impact wolf restoration efforts in the northeastern United States.
“This study brings the whole historic distribution of grey wolves into question,” said Dr. Rutledge, who is currently a post-doctoral researcher with the Natural Resources DNA Profiling and Forensic Centre (NRDPFC) at Trent. “The results challenge the idea that only grey wolves occupied eastern North America prior to the arrival of European explorers.”
The study, done in collaboration with anthropologists from Trent University, the University of Western Ontario (UWO), and McMaster University, compared the size and DNA of an approximately 500-year old jaw bone excavated from a pre-historic Iroquois village site in London, Ontario, to that of current wolf and coyote populations.
“We didn’t find any evidence that grey wolves inhabited southern Ontario in the 16th century, so these results are in direct contrast to the idea that a grey wolf subspecies inhabited the temperate forests of eastern North America,” Dr. Rutledge said. “That our results demonstrate the presence in this area of a distinct eastern wolf species rather than a grey wolf is really quite important for conservation because it makes us question the original distribution of grey wolves in the east.”
Once ranging across most of the United States, wolves were extirpated from all but a few regions by the mid 20th century. In eastern North America, these wolves were typically considered to be a grey wolf subspecies, but the genetic and morphological evidence presented in this new study reveal a different image of the wolf that roamed this area prior to European settlement.
Commenting on her research project, Dr. Rutledge said: “As a biologist, being able to collaborate with the Anthropology departments at three universities was really exciting, and being able to utilize the extensive resources available at Trent was really essential to the success of this project. The work wouldn’t have been possible without the ancient DNA facility in the Anthropology department and the sophisticated technological tools and genetic database available through the Biology department and the Natural Resources DNA Profiling and Forensic Centre (NRDPFC). I think future collaborations between the departments of Anthropology, Biology, and Indigenous Studies hold real promise for helping us unravel the natural history of wildlife populations. Ancient DNA really is the key to clarifying questions about extirpated and extinct species.”
To view the complete research article, see:
Rutledge LY, Bos KI, Pearce RJ, White BN. 2010. Genetic and morphometric analysis of sixteenth century Canis skull fragments: implications for historic eastern and gray wolf distribution in North America. Conservation Genetics 11: 1273-1281.
Student from B.C. names red seaweed after colourful movie director
Bridgette Clarkson titles new species as a tribute to Tim Burton’s ‘strange imagination’
By: Todd Coyne, Vancouver Sun, May 13, 2010, p. A5
Director Tim Burton has won many accolades during his successful career, but a B.C.-born researcher at the University of New Brunswick has honoured the filmmaker with an aptly bizarre tribute—seaweed.
Bridget Clarkston, a 29-year-old UNB doctoral student from Comox, decided to name the new species of red seaweed Euthora timburtonii as a tribute to the “similarly strange imaginations” she said she and the director share.
“I love The Nightmare Before Christmas and I love Tim Burton films because of his visual style,” said Clarkston. “His drawings are always a little bit dark, a little bit strange.”
Clarkston initially discovered the seaweed in 2007 off the coast of Bamfield, just across Vancouver Island from the beaches where she grew up. But Clarkston said that during the peer-review and verification phases since her 2007 discovery, the seaweed has also turned up in Tahsis, B.C., Friday Harbor, Wash., and even as far north as Haida Gwaii.
“There are lots of different types of red seaweeds in British Columbia—it’s very diverse compared to the rest of Canada,” said Clarkston on the phone from Fredericton. “The Pacific is much more diverse than the Atlantic … it’s an older ocean and there was a lot more time for species to evolve over there.”
Two weeks ago Clarkston sent letters to Burton, who is now judging at the Cannes Film Festival in France, by way of his agent and production company to alert them of her use of the director’s namesake. She has not yet heard anything back.
In the meantime, Clarkston already has two other new species and a whole new genus—a species classification—of red seaweed that she said she has discovered in B.C.
She has not yet submitted these species and genus for review but is confident that they are truly unique finds.
Clarkston plans to name her new genus Salishia, after Salish Sea, the alternate name proposed for the waters of the Strait of Georgia, Puget Sound and the Strait of Juan de Fuca, where the new genus of seaweed species is found.
In keeping with the otherworldly, Burton-esque naming scheme, Clarkston intends to call one of these yet-to-be published species Pugetia cryptica.
The other she will name Beringia wynnei after one of Clarkston’s heroes and marine biology predecessors, American phycologist Michael Wynne.
Though still rare, according to Clarkston, new species discoveries such as these are made increasingly easy to verify thanks to initiatives like the Barcode of Life project led by researchers at the University of Guelph in Ontario.
“It’s a real Canadian-driven initiative to sequence a standard genetic marker for every species on the planet—all plants, animals, fungi, protists. It’s like a global survey of all species,” said Clarkston. “This whole species discovery aspect of my research is all part of that Barcode of Life initiative funded by Genome Canada and the University of Guelph.”
Is ‘momnesia’ a real condition or an urban myth?
Vancouver-based researchers investigate the impact of pregnancy, including the child’s sex, on memory and cognition
By Chad Skelton, Vancouver Sun – May 8, 2010, p. A23
Liisa Galea is an award-winning researcher at the University of B.C. with a PhD in neuroscience.
So it was more than a little embarrassing for her when, pregnant with her second child, she couldn’t remember where her car was parked.
She knew she’d left it in the parkade across the street from her UBC office. But, for the life of her, she couldn’t recall what level she was on.
Even worse, this didn’t happen to her just once or twice—but nearly a dozen times throughout her third trimester.
Galea is far from the first woman to forget things during pregnancy, a phenomenon so common it goes by many names: “momnesia,” “baby brain” and “dumb Mom syndrome.”
But as an expert in the field of neuroendocrinology—the link between hormones and the brain—Galea was in a unique position to figure out what was going on.
In the decade since her parking problems, Galea has undertaken a number of studies on the impact of pregnancy on the brain, mainly on rats.
She’s found that pregnant rats are worse at making their way through mazes than non-pregnant rats and that their hippocampus (an area of the brain key to memory) is smaller.
And Galea’s just one of several Vancouver-based researchers trying to figure out whether “baby brain” is a real condition or just an urban legend.
Forgetful or just distracted?
On the face of it, the notion that having a child might impact a woman’s brain function is not that surprising. There’s plenty of evidence that hormones can affect thinking. And pregnancy has a uniquely dramatic effect on hormone levels—estrogen, for example, can reach concentrations 1,000 times normal.
When surveyed by researchers, almost all pregnant women say they suffer at least some memory problems and difficulty focusing.
But studies that try to test pregnant women’s memory in the lab have been decidedly mixed: some studies find they perform worse than non-pregnant women while others have not. Carrie Cuttler, a post-doctoral fellow at UBC and a colleague of Galea’s, began to wonder whether the lab itself might be the problem.
In a not-yet-published study, Cuttler and her colleagues asked 60 pregnant women and 24 non-pregnant women to perform a series of memory tests in their lab, such as repeating back a list of words.
As expected, the pregnant women did as well as the nonpregnant women on almost all the tests.
But that wasn’t the end of the study. As the women were leaving, Cuttler gave them a short, one-page questionnaire and asked them to mail it back to her the next day.
“It was stamped, it was addressed, it was ready to go,” said Cuttler. “All they had to do was pop it in the mailbox.”
Which is exactly what 70 per cent of the non-pregnant women did.
And the pregnant women? Just over half of those in their second and third trimester remembered to mail the letter.
And only one in four of those in the first trimester mailed it back.
Cuttler says the fact so many “baby brain” studies are conducted in the lab may be masking the extent of the problem—because for a harried, pregnant woman, a lab may be the first moment’s peace they’ve had all week.
“Pregnant women can perform on these cognitive tasks with little difficulty when they’re in a sterile, distraction-free environment, where they can focus on the task at hand,” she said. “But if you put them in the real world where they’ve got … family issues [and] work issues, their attention is much more divided. They have a lot more going on. That’s when you see the deficit.”
Cuttler said her study also suggests that “baby brain” may have less to do with brain chemistry and more to do with the sheer number of things a pregnant woman has to think about, from prenatal vitamins to doctor’s appointments.
That may explain why women in the first trimester—who’ve had the least amount of time to get used to being pregnant—fared the worst in Cuttler’s study.
A nice thing about her study, said Cuttler, is that it suggests pregnant women’s mental performance in the workplace need not suffer.
“If you put a pregnant woman in a quiet, distraction-free environment she can perform as well as a non-pregnant woman,” said Cuttler. “Maybe just don’t ask her to do a hundred things at once.”
Baby’s sex a factor
How many distractions a pregnant woman has in her life may not be the only thing affecting her brain.
Whether she’s carrying a boy or a girl also seems to make a big difference.
A few years ago, Neil Watson, a psychology professor at Simon Fraser University, conducted a study that looked at how 39 pregnant women—26 carrying boys, 13 carrying girls—performed on tests of their memory from early pregnancy to several months after delivery.
The study found a surprisingly significant gap in memory performance based on the sex of the mother’s fetus: those carrying boys scored about 25 per cent better on memory tests than those carrying girls.
Watson said he’s curious what’s behind the gender gap and is conducting followup research to try to figure out what’s going on.
One of the most puzzling aspects of the original study, he said, is how persistent the gender gap was.
Boys release different hormones into their mother’s system than girls. If that’s the cause of the memory gap, said Watson, you’d expect the gap to be much wider at some stages of pregnancy than others.
Instead, his study found the gap between “boy moms” and “girl moms” persisted from the first test, at eight weeks gestation, until months after delivery.
Which raises another, far more controversial possibility, said Watson: That carrying boys doesn’t necessarily make women smarter. Rather, smart women may be more likely to have boys.
Watson stresses he has no evidence yet to support this hypothesis—and said that, as a father of three daughters, he’s not personally advocating it.
But he notes that, in other species, it’s been shown that females can sometimes bias the sex of their children when having one gender or the other is an evolutionary advantage.
Whether humans might do the same, he said, is a “fascinating possibility.”
The possible reverse effect of motherhood
Having experienced baby brain firsthand, Galea sympathizes with women who worry being pregnant is making them dumber.
And she notes the research on the topic isn’t all discouraging.
For example, take those rats who fumbled their way around Galea’s mazes during pregnancy.
When Galea tests rats later in life, after their children have left the nest, they perform better than rats who’ve never had kids.
And other studies have suggested mother rats are less susceptible to degenerative brain illnesses like Alzheimer’s than non-mother rats.
No study has yet been done looking at the long-term effects of motherhood on the human brain.
But Galea can’t help but think that, if pregnancy impairs memory and cognition, the long-term mental effort involved in being a mother might actually do the opposite.
“When you’re a mom you’ve got to remember your kids’ doctor’s appointments, their dentist’s appointment, their shots,” she said.
“Before you were just taking care of yourself. Now you’re taking care of another human being.”
Study suggests link between abortion, mental health disorders
Patients showing signs of mood disorders, drug abuse should be screened
By Jen Skerritt, Vancouver Sun, May 1, 2010, p. B5
Depression and substance abuse plague about half of American women who reported having an abortion, according to a University of Manitoba study.
The study, published in the Canadian Journal of Psychology, suggests there’s an association between mental disorders and abortion and that doctors should screen for a history of abortion in women who present symptoms of anxiety, mood disorders and substance abuse.
However, researchers are adamant the findings do not conclude abortion causes mental disorders or drug abuse, saying the study did not examine other factors—including whether the mental disorder existed before a woman had an abortion.
The study analysed data collected from 3,310 women by the National Institute of Mental Health and the National Institute of Drug Abuse in the U.S. between 2001 and 2003.
Layperson interviewers asked women if they ever had an abortion in their lifetime, and used guidelines from the World Health Organization to assess such mental conditions as major depression, suicide, alcohol abuse and panic attacks.
Researchers found drug and alcohol abuse was more prevalent among women who reported having an abortion sometime in their life. About 25 per cent of women who had an abortion reported some form of substance abuse in their lifetime, compared to seven per cent of women who did not have abortions.
The study also found women who had an abortion had an increased likelihood of mood and anxiety disorders, although the relation is weaker and less consistent. Researchers speculate other factors, such as violence and poor social supports, may contribute to mental disorders.
Natalie Mota, a U of M graduate student who was the study’s primary author, said the findings are unclear.
“You absolutely cannot say from this data that an abortion causes mental illness. There’s an association present, but whether the mental illness comes before or after needs to be further examined.”
The study did not examine what portion of the abortions were medically necessary or elective, and said “unintended pregnancy itself may be a stressful event that can be a confounding factor in the relation between abortion and mental illness.”
Mota speculates the connection between substance abuse and abortion was strong because it’s possible that women self-medicate with drugs and alcohol following an abortion, although the study did not investigate this.
Mota said it’s important the study is not misinterpreted, and that people understand researchers found an “association” between mental disorders and abortions, not a “cause and effect” relationship.
“There is a possibility the person was diagnosed with a mental disorder and 20 years passed and they had an abortion,” Mota said.
Abortion providers worry the study’s findings could be misinterpreted and become fodder for anti-abortion groups.
“I think there are lots and lots of questions about this study and I would like to see some answers to those before I know it has any affect as an abortion provider and the way I provide my service,” said Joan Dawkins, executive director of the Women’s Health Clinic in Winnipeg.
Vision centres of blind person’s brain recycled to help other senses
By Thandi Fletcher, Vancouver Sun April 28, 2010, p. B 3
Despite popular belief, blind people don’t have a better sense of smell than people with sight, a Canadian study suggests.
University of Montreal graduate student Mathilde Beaulieu-Lefebvre debunked the myth that blind people have a more acute sense of smell, finding instead they simply are more conscious of odours around them.
“The urban legend is not true,” Beaulieu-Lefebvre said.
It’s not their sense of smell that’s different, but rather the way blind people use their noses, she said. For example, while a sighted person can simply look at food and tell if it’s gone bad, a blind person relies solely on smell to recognize good food from spoiled food.
“In the absence of vision, [blind people] have to rely on other cues, like smell or sound,” Beaulieu-Lefebvre said.
However, the study did find that blind people process odour information in their brains differently from sighted people.
Using a type of MRI scan, the researchers discovered that when blind people smell something, they use the part of the brain connected to the nose more than other people. They also found that—despite having lost their sense of vision—blind people still use the occipital cortex, the part of the brain used for vision.
“This part of the brain is sort of recycled to do tasks other than vision, such as smelling or touching or hearing,” explained Beaulieu-Lefebvre.
The study’s findings can help researchers better understand how the human brain works, Beaulieu-Lefebvre said.
“This gives hope to blind people in understanding that the brain is not hardwired,” she said. “It can be reorganized to do different tasks.”
The research can also help to develop a rehabilitation program for the blind, where they can learn how to navigate through an environment based on smell, she said.
Mike Potvin, who lost his vision at 25 to a rare hereditary disorder called Leber’s optic neuropathy, is not surprised by the study’s findings.
Beaulieu-Lefebvre will be presenting her findings in June at a conference for the Organization for Human Brain Mapping.
Breast cancer linked to chemical exposure
Study points to synthetic fibres, petroleum products
Vancouver Sun – April 1, 2010, p. B2
Exposure to certain chemicals and pollutants before a woman reaches her mid-30s could triple her risk of developing breast cancer after menopause, Canadian scientists said on Thursday.
In a study in Occupational and Environmental Medicine, a British Medical Journal title, the researchers found that women exposed to synthetic fibres and petroleum products during the course of their work appeared to be most at risk.
“Occupational exposure to acrylic and nylon fibres, and to polycyclic aromatic hydrocarbons may increase the risk of developing post-menopausal breast cancer,” they wrote.
But some experts commenting on the study expressed caution, saying such links can crop up by chance.
“In a study of this sort, positive associations often occur simply by chance,” said David Coggon, a professor of occupational and environmental medicine at Britain’s Southampton University. “They carry little weight in the absence of stronger supportive evidence from other research.”
The Canadian scientists conceded their findings could be due to chance, but also said they were consistent with the theory that breast tissue is more sensitive to harmful chemicals if the exposure occurs when breast cells are still active—in other words, before a woman reaches her 40s.
The researchers, from Montreal’s Occupational Health Research Institute based their findings on more than 1,100 women, 556 of whom were diagnosed with breast cancer in 1996 and 1997 when they were aged between 50 and 75 and had gone through the menopause.
A team of chemists and industrial hygienists investigated the women’s levels of exposure to around 300 different substances during their employment history.
After taking account of the usual factors associated with an increased risk of breast cancer, the analysis indicated a link between occupational exposure to several of these substances, the Montreal team wrote.
Compared with the comparison group, the risk peaked for exposures before the age of 36, and increased with each additional decade of exposure before this age, they found.
This meant women who were exposed to acrylic fibres appeared to run a seven-fold risk of breast cancer, while those exposed to nylon fibres almost doubled their risk.
The scientists said more detailed studies focusing on certain chemicals were now needed to try to establish what role chemical exposure plays in the development of breast cancer.
Reuters
The study Postmenopausal breast cancer and occupational exposures is authored by France Labrèche (Occupational Health, Quebec National Institute of Public Health, Montreal, Quebec, Canada, Départements de Médecine sociale et préventive et de Santé environnementale et santé au travail, Université de Montréal, Montreal, Quebec, Canada), Mark S Goldberg (Department of Medicine, McGill University, Montreal, Quebec, Canada), Marie-France Valois (Division of Clinical Epidemiology, McGill University Health Center, Montreal, Quebec, Canada) and Louise Nadon (INRS-Institut Armand-Frappier, Laval, Quebec, Canada) and can be found at Occup Environ Med 2010;67:263-269. The abstract is below.
Abstract
Objective To determine whether exposures in the workplace to organic solvents and to other agents, such as polycyclic aromatic hydrocarbons, are associated with increased risks of developing postmenopausal breast cancer.
Methods Between 1996 and 1997 a case–control study was conducted in Montreal, Quebec. Cases comprised 556 women, aged 50–75 years, with incident malignant breast cancer, and their controls were 613 women with other cancers, frequency matched for age, date of diagnosis and hospital. An expert team of chemists and industrial hygienists translated their job histories into exposure to about 300 agents.
Results Odds ratios (ORs) were increased for the usual risk factors for breast cancer and, adjusting for these, risks increased with occupational exposure to several agents, and were highest for exposures occurring before age 36 years. Increased ORs were found for each 10-year increment in duration of exposure, before age 36 years (OR<36), to acrylic fibres (OR<36=7.69) and to nylon fibres (OR<36=1.99). For oestrogen-positive and progesterone-negative tumours, the OR doubled or more for each 10-year increase in exposure to monoaromatic hydrocarbons, and to acrylic and rayon fibres. The OR<36 also doubled for exposure to organic solvents that metabolise into reactive oxygen species, and to acrylic fibres. A threefold increase was found for oestrogen- and progesterone-positive tumours, with exposure to polycyclic aromatic hydrocarbons from petroleum sources.
Conclusion Certain occupational exposures appear to increase the risk of developing postmenopausal breast cancer, although some findings might be due to chance or to undetected bias. Our findings are consistent with the hypothesis that breast tissue is more sensitive to adverse effects if exposure occurs when breast cells are still proliferating. More refined analyses, adjusting for hormonal receptor subtypes and studies focusing on certain chemical exposures are required to further our understanding of the role of chemicals in the development of breast cancer.
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Collider’s first test a smashing success
Data collected will help to explain how the universe works
By Margaret Munro, Canwest News Service – March 31, 2010, p. B3
Isabel Trigger and her husband Rob McPherson were a bit sleep-deprived after the much anticipated and oft delayed collision in the tunnel under the Swiss-French border Tuesday.
But the physics power couple, key players on the Canadian team involved with the unprecedented international experiment, are ecstatic to see the Large Hadron Collider finally smashing subatomic particles.
“It really is fantastic,” Trigger said from the TRIUMF national physics laboratory at the University of B.C. after Tuesday’s collision in Europe.
The protons collided 100 metres underground just after 1 p.m. Central European time.
Whoops and cheers filled the crowded control room at CERN, the European Organization for Nuclear Research, near Geneva and were echoed by physicists from Tokyo to Toronto.
“This is the breakthrough movement we have all been waiting for,” says McPherson, a professor at University of Victoria and principal investor of the Canadian team that helped design, build and commission the most complicated machine ever.
The Large Hadron Collider is designed to collide proton beams at energies not seen since the milliseconds after the Big Bang—prompting some to dub it the Big Bang: The Sequel.
The scientists were marvelling Tuesday over the quality and volume of the data from the “events” generated as the machine finally went live.
“The amazing thing is not that they got them to collide,” says Trigger, “but that since then we’ve had in the order of a million events in ATLAS.”
ATLAS is one of the cathedral-sized detectors inside the collider that runs in a circular 27-kilometre long circular tunnel under the Swiss-French border. Scientists have spent almost 20 years designing and building the collider that ran into serious problems when it was first fired up in 2008, resulting in an explosion. They are taking it slower this time and will run the collider at half power for the next year and half.
The detectors will record everything that happens when proton beams collide. There is so much data that it is being been sent to a network of “computing farms” around the world, including one humming away at a processing centre at TRIUMF, which is tucked in the woods on the edge of the UBC campus.
Nigel Lockyer, TRIUMF’s director, says it is all pretty remarkable.
“The protons beams collide in Geneva, they go through this incredible detector with millions of sensors, then the electronic signals are transferred to computers that end up sending light signals across the Atlantic and across Canada all the way to TRIUMF,” he says. “And then, if somebody in Japan wants to access data, they have to cross the Pacific to get to Canada.”
Canada’s contribution to the project has cost close to $100 million over the last 15 years, which Lockyer describes as “an absolute steal for Canada.”
About 200 people are currently involved, including 100 graduate students who will be among the first to “study matter at this new energy frontier,” says McPherson.
Researchers are hoping for new understanding of how the universe works. They hope to discover new forces, new dimensions, and perhaps even find the Higgs boson, a theoretical particle that may be responsible for mass.
“With a little luck, nature will be kind to us,” says Trigger, group leader of the ATLAS team at TRIUMF. She likens the task to looking for needles in a haystack because there will be so much data to sift through.
Fin fish aquaculture in coastal British Columbia waters
Sharon DeDominicis, RPBio
Sharon DeDominicis is the Environmental Sustainability Manager for Marine Harvest Canada, the largest salmon aquaculture company in British Columbia and the world. She has a
Bachelor of Science degree (Ecology) from the University of Calgary and has been a Registered Professional Biologist since 1991 (Province of Alberta, then British Columbia). Over her 25 year career she has authored more than 200 environmental impact assessments for a variety of resource sectors, focusing exclusively on aquaculture since 2001. In addition to managing provincial and federal regulatory compliance, she represents Marine Harvest Canada on several technical advisory boards, including the British Columbia Salmon
Farmers Technical Working Group and the Province of British Columbia Finfish Aquaculture Waste Control Regulation Advisory Group, and the Department of Fisheries and Oceans Monitoring, Inspection and Auditing Technical Committee. Scope of work includes active engagement with environmental groups such as the Coastal Alliance for Aquaculture Reform (CAAR), World Wildlife Fund and First Nation collaborative projects, and collaborative projects with academia and government researchers. Sharon has been the recipient of several awards including the Outstanding Woman of Honor – Aquaculture Sector (2007) from the Women of Resource Communities, and has been nominated for environmental manager of the year (Aquaculture Sector) in 2007 and 2008.
Question 1. What do you think are the key issues surrounding open water fin fish aquaculture (fish farming) on B.C.’s coast?
From the perspective of a professional biologist working in the fin-fish aquaculture sector, I see three overarching challenges for the sector: business related (meeting global demands
for the product), biological performance (stock health, environmental impacts), and public perception. Effectively reducing public concern related to environmental impacts associated with fish farming is critical for the success of the industry. Salmon farming needs to incorporate a variety of ideological perspectives to focus on environmental solutions, engage public interests and communicate well to secure its social license.
The global demand for finfish and shellfish is growing by about 9 percent a year (FOC 2009) applying considerable pressure to the world’s capture fisheries. According to the United Nations Food and Agriculture Organization, by 2005 75% of the world’s capture fisheries were at – or near – their maximum harvest rates (http://www.fao.org/docrep/009/a0699e/A069 9E05.htm ). Aquaculture is an important part of the world’s food supply and by 2020 will likely provide quantities of fish comparable to wild fisheries. Canada, with the world’s
longest coastline, has a huge potential for aquaculture, yet in 2006 it ranked 23rd among world aquaculture producers and contributed less than 0.3% of the total global output (FOC
2009).
Modern salmon culture in the Pacific region includes stock enhancement, farming and ranching – tracing its origins to hatchery technology developed to mitigate stock impacts to Pacific Northwest riverine systems, from anthropogenic activities such as the construction of hydroelectric dams. This eventually evolved into enhancement and ranching programs that currently release more than 5 billion fry into the wild environment from Canada, Russia, Japan and the United States every year (Beamish et al. 1997). Many of these fish are later captured by commercial and recreational fishermen as ‘wild’ salmon. Up to 80 % of the juvenile coho salmon in southern BC coastal waters have been attributed to enhancement projects (Noakes et al. 2000). Commercial salmon farming shares the same genesis and much of the same technology; the main difference being, the stock is held captive throughout its life cycle.
From an animal husbandry perspective, raising stock in an uncontrolled environment such as marine areas requires extensive knowledge of the ocean and health requirements of the
species or stock. Over the past 30 years, considerable strides in understanding ocean hydrodynamics, marine chemistry, phytoplankton, salmonid pathogens (viral and bacterial), external parasites, marine engineering and infrastructure have been made. Fish health research has provided techniques for rapid disease diagnosis and treatment. Vaccines have been developed for the most common bacterial (and even for some viral) agents. Advances in adult salmon fish health management and nutrition along with success in maintaining healthy, disease free stocks of fish have been well documented in the animal science literature. Unfortunately, because this is such a specialized industry, substantive improvements in marine husbandry are not well understood and/or well known, particularly by the general public or by the salmon enhancement sector. Reducing stock mortality during occasional periods of critically low dissolved oxygen and/or during harmful algae blooms continues to be a principal challenge facing the Pacific coast industry.
It is appropriate for the public to hold any industry or sector accountable for any negative impacts to public resources used in the course of their operations – in this case ocean ater, the soils beneath the cages and wild fisheries resources. At the same time it is important these same citizen interests be made aware of the management actions taken to address these issues and the progress made towards mitigation/reduction/elimination of these concerns. The inability to effectively communicate technological and environmental gains has been a marked failure of the industry. For example the view presented by some sources and widely covered by the media holds that sea lice from farmed salmon are a significant factor in the disappearance of Fraser River sockeye salmon. Yet, even a superficial examination of the state of knowledge here reveals much information that questions this assertion. This includes: i) no research has yet demonstrated sea lice infestation to cause morbidity or mortality to juvenile sockeye salmon; ii) the weight of research findings into the impact of sea lice on wild pink salmon feared to be significant, even leading to extinction, have not found an effect at the population level (BC PSF 2009); iii) salmon farms can currently control the numbers of sea lice on their stocks to ensure that they remain at or below the ambient levels in the marine environment; and iv) the species of sea lice most commonly reported on juvenile sockeye (Caligus clemensi) is not specific to salmon and has a low abundance on farmed salmon. While this information may provide balance when reviewed and understood in its totality, the message most frequently offered by mainstream media is that of uncontrolled harm.
Question 2. Where do you think there is room for improvement in regards to fish farm management in coastal British Columbia by all sectors involved?
Industry success will be determined by its economic, social and environmental sustainability. Economic and environmental sustainability require regulatory certainty and consistency, science and innovation. Political stability is fundamental to build industry and public confidence. The British Columbian aquaculture industry is currently experiencing a change in regulatory authority following a British Columbia Supreme Court (BCSC) decision in February 2009 that ruled that the activity of aquaculture is a fishery which falls under exclusive federal jurisdiction pursuant to sub-section 91(12) of the Constitution Act, 1867 – Sea Coast and Inland Fisheries. In 2008, the federal government announced of a $70 million 5-year plan to support aquaculture innovation ($25 million), improve governance ($13 million), advance regulatory science ($22 million) and facilitate certification and market access ($10 million) (DFO October 2008).
Management of the sector is likely to improve with an expanded focus on collaboration amongst First Nations, environmental groups, governments, academics, industry, local communities and interested parties. Emergence of this approach to governance can be demonstrated in examples such as the Framework for Dialogue agreement struck between the Coastal Alliance for Aquaculture Reform (CAAR) and Marine Harvest Canada (MHC) in January 2006. The agreement provides opportunities for discussion around a number of matters of mutual interest including collaborative research on sea lice, sustainable technology innovation and public communication. Demonstrated value of the relationship is evidenced in the joint support of a Coordinated Area Management Plan (CAMP) for the Broughton Archipelago, where salmon production is coordinated to create fallow routes for juvenile wild salmon migrating from their natal streams. A key element of CAMP is the establishment of a collaborative monitoring/research program to ascertain the effectiveness/biological utility of the out migration corridors and related management activities.
Progressive industries recognize the value in investments in innovation. Although there are currently no viable commercial-scale closed containment systems for rearing salmon operating anywhere in the world, advances in technology may make closed containment systems viable in the future. We have completed a number of pilot projects here in British Columbia and continue to invest in joint ventures and studies to measure success and weigh all environmental factors. Two problem areas with current closed containment systems are the use of fossil fuels to maintain water temperature, growing conditions and associated fish health impacts. For a report analyzing more than 40 closed containment systems from around the world please see http://www.dfompo.gc.ca/csas/Csas/Publications/SARAS/2008/2008_001_e.htm
Question 3. Can you suggest specific measure or steps which can be taken to resolve this debate before another decade goes by?
Unfortunately, at present, the dialogue on the risks and benefits of farming fish is mired in polarized debate with positional language and accusations serving as the foundation for discussion rather than development of science-based discussions. Historical evidence suggests that it often takes decades for applied science to resolve issues, especially with regard to emerging industries and technologies. As information builds the debate continues on finer and finer areas of knowledge, and the initial hypotheses continually evolve and refine.
Growth of the Canadian aquaculture sector has been slow compared to other jurisdictions largely due to divergent opinions on the sustainability of the newly emerging agribusiness. The differing opinions arise in part from the newness of the industry along the coastline (where fish harvesting has been dominated by wild and enhanced stock capture) and also due to the lack of locally relevant science assessing the potential impacts of the industry. In 1984 there were 10 salmon farms operating on the British Columbia coast, by 1988 there were 101 salmon farming companies and 118 active farms (Peter Robson 2006). By 1992, about half of the companies had disappeared from the coast due to technical challenges growing the stock, financial instability, poor site selection and a drop in salmon prices in the marketplace. The rapid growth in the industry occurred in the absence of a coordinated regulatory system. Increasing public concerns about the effects of the industry on the marine environment and on other coastal users led to a provincially mandated moratorium on expansion in 1986 and again in 1995 while complex multi-stakeholder environmental assessments of the industry were completed (Gillespie Enquiry 1986, Salmon Aquaculture Review 1997).
There have been three science-based reviews of the industry: Gillespie Enquiry, SAR, and the United States National Oceanic and Atmospheric Administration (NOAA) in 2001. The
over-arching conclusion was that the salmon farming industry, at the time of review, presented a low overall risk to the environment. Continued regulatory and public focus on aquaculture led to the broader based Legislative Assembly of British Columbia Special Committee on Sustainable Aquaculture (November 2005 to May 2007) and another sciencebased review conducted by the Pacific Salmon Forum (December 2004 to January 2009) http://www.pacificsalmonforum.ca
In response to continuing public uncertainty provincial and federal regulatory agencies have adopted a precautionary approach to managing the industry – while investing considerable resources into research projects to further the body of BC specific science. Research includes studies on sea lice, benthic monitoring, feed conversion ratios, fish health, and closed
containment systems. A list of studies can be found at http://www.salmonfarmers.org/studies_and_publications.php or on government websites (DFO, Ministry of Environment, MAL).
Management of the fish farm industry has been in a evolving since farms first appeared on the coast. The British Columbia salmon farming industry is subject to 52 separate provincial and federal statutes, regulations, policies and guidelines, as well as numerous municipal and regional district land use and development regulatory instruments. A regulatory comparison chart can be found at http://www.al.gov.bc.ca/fisheries/Finfish/cabinet/Summary_Table_BCWorld_Aqua_Regs.pdf
Since 2003 the industry has been monitoring and reporting sea lice information to government authorities as part of a broader program known as the Provincial Sea Lice Management Strategy. The results are publically available on the MAL website (http://www.al.gov.bc.ca/ahc/fish_health/sealice_monitoring_results.htm ) and at some company websites (example, http://www.marineharvestcanada.com ). In addition to regular monitoring, treatment trigger levels were established in 2003 which are comparable to other international jurisdictions. Serious health and growth performance issues associated with sea lice infestations have plagued the salmon farming industries in Europe and eastern North America. This has not been the case in either Japan or Canada’s west coast (Johnson et al. 2004). Heavy infestations resulting in mortality or damage to farmed Pacific or Atlantic salmon stocks from sea lice infections are rare in BC.
Over the past 7 years (2003-2010) our knowledge of sea lice biology (life history, distribution, abundances, tolerances) and the susceptibility and resistance of salmonids to lice has substantially improved. Significant findings relevant to the BC situation are listed below.
1. There are several different species of sea lice that infect salmonids in the marine waters of British Columbia, the two most common are Lepeophtheirus salmonis and Caligus clemensi. Most of the ‘sea lice debate’ focuses on the interactions between farmed Atlantic salmon (Salmo salar), juvenile Pink salmon (Oncorhynchus gorbuscha) and L. salmonis.
2. Recent studies have found significant genetic differences between Pacific and Atlantic L. salmonis, suggesting the two groups may be different species, which may explain the different clinical presentation of sea lice impacts in farmed salmon internationally (Todd et al 2004; Yazawa et al 2008).
3. Resistance to sea lice varies between salmon species. Studies report that when Pink salmon weighing less than 25g were exposed to > 200 L. salmonis/salmon about
50% became infected but there was no death or signs of sickness and within 3 weeks post infection most of the infected fish had shed the lice. By contrast, 100% of Atlantic salmon became infected, and died or were seriously sick within 12 days post infection when similarly infected (50g fish) (Ross et al 2000; Jones et al 2007; Wagner et al 2007; Jones et. al 2008).
4. Pink salmon appear to be highly resistant to sea lice infections. In fact, very little mortality was associated with laboratory studies on fish larger than 0.7g (Jones et al 2008b). It has been estimated that Pink salmon immunity to sea lice is fully developed by the time Pink salmon are less than 1.0 grams in size and appears to coincide with changes to the
skin, including the start of scale development (Jones et al 2008b).
5. Both laboratory and field studies have demonstrated the ability of Pink salmon to shed lice. One study found that this ability was not compromised even when salmon were held on reduced ration to the point that they were smaller and skinnier than the controls (Jones et al 2008a).
6. Recent research by Fisheries and Oceans Canada has shown that the proportion of wild Pink salmon juveniles at risk from sea lice declined from 4.5% to 0% between 2005 and 2009 in the Broughton Archipelago region. In the spring of 2008, there were no recorded lethal infections of L. salmonis on Pink salmon less than 0.7 grams in this region (lethal size thresholds based on published trials). In 2009, similar observations show that no Pink salmon less than 0.7 grams were at risk to L. salmonis.
7. When wild juvenile pinks were surveyed off the north coast of BC, (a region devoid of salmon farms) prevalence of all lice on the wild salmon was found to be over 13% (i.e. 13% of fish carried lice), and intensity averaged 1.2 lice/fish. C. clemensi were more predominant than L. salmonis (Gottesfeld et al. 2005). Similar results were found in wild juvenile pink salmon surveyed in the midcoast of BC, another region with a few salmon farms. In this region, prevalence and intensity were 18% and 2 lice per fish respectively (Butterworth et al. 2007). However in this study more L. salmonis than C. clemensi were observed.
8. Farming companies continue to refine management techniques in response to research results. Sea lice management (monitoring and treatment) is intensified during the critical outmigration period when wild salmon are at their smallest (March – May). There has been a steady decrease in farm sea lice numbers since 2007 in the Broughton (http://www.agf.gov.bc.ca/ahc/fish_health/sealice_monitoring_results.htm ).
9. Management practices and production tonnage in the Broughton Archipelago have been relatively consistent from 2003-2009, yet pink salmon returns continue to be as variable as they have been historically (http://www.pac.dfompo.gc.ca/science/aquaculture/pinksalmon-saumonrose/resultsresultats/index-eng.htm ).
10. Peak pink salmon returns occurred in 2009 in the Broughton (and elsewhere along the coastline). Historical highs were also reported 1975, 1993 and 2001 in the archipelago. Conversely, historical lows were reported 1953, 1969, 1991 and 2002 (http://www-ops2.pac.dfompo.gc.ca/xnet/content/salmon/sc stad/bulletins.htm ).
11. Even with all the monitoring and management, the farms are administering very few treatments (normally no more than 1.5 treatments/crop cycle) (Dr. Sonja Saksida personal communication; http://www.marineharvestcanada.com )
Question 4. How would you suggest ways in which biology professionals can become better informed and involved in addressing fish farm issues?
Websites and blogs devoted to salmon farming issues tend to be either pro (example: company or farming association sites http://www.marineharvestcanada.com ) or con (example: http://www.farmedanddangerous.org) regarding the issues of concern and progress made to address concerns. Frequent reviews of these sources will make an interested biologist
aware of the current state of debate around salmon farming but may be repetitious with respect to narrow source material or may not provide the desired level of information
balance. The recent report by Pacific Salmon Forum with its appendix of research findings is a timely and concise reference http://www.pacificsalmonforum.ca. Of course, a good source of information can be colleagues working directly in the field.
Much of the BC environmental impact research has been conducted by biologists who are CAB members and enquiries made through the APB list serve may elicit private responses and communication with professionals who were directly involved in the field work and data analysis. Similarly many of those given the responsibility for monitoring the performance of this industry to the targets and thresholds established in regulations for environmental sustainability are CAB professionals.
Employment opportunities exist through various avenues including government, universities, advocacy groups and industry. Institutions and agencies involved with salmon aquaculture include but are not limited to: Fisheries and Oceans Canada, Ministry of Environment, Ministry of Agriculture and Lands, University of British Columbia, University of Victoria, Vancouver Island University, Center for Aquatic Health Sciences (Campbell River) and the Pacific Salmon Foundation. Opportunities for upgrade training in salmon aquaculture are available through many post secondary teaching institutions.
Salmon farm tours are available each year from July to September through the BC Salmon Farmers Association http://www.salmonfarmers.org/tours.php
Formal Dialogues provide another opportunity for biology professionals and multiple stakeholders to work towards common goals and understanding. These dialogues also allow interested parties to contribute to global initiatives that are working to build a more accountable, and therefore stronger, salmon farming industry. Such is the case with salmon
aquaculture’s involvement with the World Wildlife Fund’s Salmon Aquaculture Dialogue (http://www.worldwildlife.org/what/globalmarkets/aquaculture/dialoguessalmon.html) and Global Aquaculture Alliance’s Global Aquaculture Standard.
Question 5. How do you envision fish farming being part of the future economic, environmental and social fabric of BC’s coast?
Farmed salmon is already British Columbia’s largest agricultural export, employing over 6,000 people in production and supply and services (Price Waterhouse Coopers 2008 report). http://proxy.baremetal.com/salmonfarmers.org/attachments/2008_IndustryProfile_PWC.pdf
Future developments will build upon the current 80,000 metric tonne annual production base and allow fish farming in British Columbia to achieve its full potential of contributing 150,000 to 200,000 tonnes to domestic and international markets. At this scale of production, BC would see benefit from the expansion of associated spin off industries such as net and cage manufacturing as well as boat building.
In British Columbia, net-pen based salmon farming has demonstrated that it can contribute as a desirable component of the modern coastal economy and form a cornerstone of survival for remote communities. The Kitasoo Xai’xais First Nations and Marine Harvest have celebrated a decade of cooperative success bringing significant benefit to the community of Klemtu and representing a positive model for other First Nations groups in coastal BC. The Quatsino and Kwakiutl First Nations have also experienced similar successes with salmon aquaculture.
Continued focus on problem solving through innovation will likely realize further reductions in the risks of stock mortality and improved environmental management. Similarly, advancements leading to reduced costs of operation will allow the advent of closed system aquaculture or full recirculation plants that will be located near sources of three phase electricity and likely closer to larger population centers.
Species diversification remains an area of strong interest in BC aquaculture with the potential for several high value species still in the experimental stages. Integrated multi-trophic aquaculture (where more than 1 species is grown together) is currently emerging on the coast.
References:
Beamish, R.J., Mahnken, C., Neville, C.M. 1997. Hatchery and wild production of Pacific salmon in relation to large-scale natural shifts in the productivity of the marine
environment. ICES Journal of Marine Science 54: 1200-1215.
BC Pacific Salmon Forum. 2009. BC Pacific Salmon Forum Final Report & and Recommendations to the Government of British Columbia January 2009.
Butterworth,K.G., Cubitt, K.F., McKinley, R.S. 2007. The prevalence, density and impact of Lepeophtheirus salmonis (Kroyer) infestations on juvenile pink salmon (Oncorhynchus gorbuscha) from the central coast of British Columbia, Canada. Fisheries Research 91: 35-41.
Fisheries and Oceans Canada. 2009. Federal BC Aquaculture Regulation & Strategic Action Plan Initiative. Discussion Document. Prepared by Fisheries and Oceans Canada.
November 2009.
Fisheries and Oceans Canada. 2008. Sustainable Aquaculture Initiative. http://www.dfompo.gc.ca/aquaculture/sustainabledurable/sustainable-durable-eng.htm
Gottesfeld, A.S., Ryan T., Rolston D., Proctor B. 2005. Sea lice and Pink salmon smolts on the North Coast of British Columbia. Retrieved January 20, 2008 from
http://www.skeenafisheries.ca/Publication_04-05_salmon_& Sea_lice_report.pdf .
Johnson, S.C., Treasurer, J.W., Bravo, S., Nagasawa, K., Kabata, Z. 2004 A review of the impact of parasitic copepods on marine aquaculture. Zoological Studies 43: 299-243.
Jones, S.R.M, Fast, M.D., Johnson, S.C., Groman, D.B. 2007. Differential rejections of sea lice by pink and chum salmon: disease consequences and expression of
proinflammatory genes. Diseases of Aquatic Organisms 75: 229-239.
Jones, S.R.M., Fast, M.D., Johnson, S.C. 2008. Influence of reduced feed ration on Lepeophtheirus salmonis infestation and inflammatory gene expression in juvenile
pink salmon. Journal of Aquatic Animal Health 20: 103-109.
Jones, S.R.M., Kim, E., Bennett, W. 2008b. Early development of resistance to the salmon louse Lepeophtheirus salmonis (Koyer) in juvenile pink salmon Oncorhynchus gorbuscha (Walbaum). Journal of Fish Diseases 31: 1365-2761.
Noakes, D.J., Beamish, R.J., Sweeting, R., King, J. 2000. Changing the balance: interactions between hatchery and wild Pacific coho salmon in the presence of regime shifts. North Pacific Anadromous Fish Commission Bulletin 2: 155-164.
Peter A. Robson. 2006. Salmon Farming – The Whole Story. Heritage House Publishing Company Ltd. Surrey BC. 271pgs.
Ross, N.W., Firth K.J., Wang Al, Burka J.F., Johnson, S.C. 2000. Changes in hydrolytic enzyme activities of Naïve Atlantic salmon Salmo salar skin mucus due to infection with the salmon louse Lepeophtheirus salmonis and cortisol implantation. Diseases of Aquatic Organisms 41: 43-51.
Todd, C.D., Walker, A.M., Ritchie, M.G., Graves, J.A., Walker, A.F. 2004. Population genetic differentiation of sea lice (Lepeophtheirus salmonis) parasitic on Atlantic and Pacific salmonids: analysis of microsatellite DNA variation among wild and farmed hosts. Journal of Fisheries and Aquatic Sciences 61: 1176-1190.
Wagner, G.N., Fast, M.D., Johnson, S.C. 2008. Physiology and immunology of Lepeophtheirus salmonis infections of salmonids. Trends in Parasitology Volume 24 No. 4.
Yazawa, R., Yasuike, M., Leong, J., vonSchalburg, K.R., Cooper, G.A., Beetz-Sargent, M., Robb, Al, Davidson, W.S., Jones, S.R.M., Koop, B.F. 2008. EST and Microchondrial DAN sequences support a distinct Pacific form of salmon louse, Lepeophtheirus salmonis. Marine Biotechnology 10: 741-749.
BioNews Vol 20, No. 1, pp. 14-19
Wed Feb 01
