Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Humans making wildlife sick

20.02.2006


Whether it’s monkeys and AIDS or mosquitoes and the West Nile Virus, we’re used to thinking of wildlife as reservoirs for emerging infectious human diseases. But a Canadian mathematical biologist says that it’s time that we turned the tables – as often as not, it’s humans that are making the wildlife sick, often to our own detriment.

It’s a 180-degree turn in perspective that Dr. Mark Lewis says is critical to our understanding of emerging infectious diseases of both wildlife and humans. And, he says, in the case of at least one ocean-based disease outbreak, biology and math are proving to be powerful allies in helping stem the growing tide of an ocean plague.

"With emerging infectious diseases of wildlife today there’s almost always some human component," say Dr. Lewis, an NSERC-funded mathematical ecologist in the mathematics and statistics department at the University of Alberta, Edmonton, Canada.



Dr. Lewis’ lab group has used mathematical mapping tools, often in collaboration with other research groups, to document the spread of pests from the West Nile Virus to the Mountain Pine Beetle in Pacific Northwest forests.

Last year, in a landmark paper, he helped document how commercial salmon farms off Canada’s British Columbia coast are a breeding ground for sea lice, a parasite that then infects young wild Pacific salmon. The research was the first to document the parasitic impact of commercial salmon farms on wild salmon in the Pacific Northwest.

Dr. Lewis and University of Alberta doctoral student Marty Krkosek, who led the sea lice research, are co-presenting their latest sea lice and salmon findings as part of a symposium called The Rising Tide of Ocean Plagues, February 17 at the Annual Meeting of the American Association for the Advancement of Science in St. Louis.

Dr. Lewis is a leader in applying mathematical tools to modelling environmental interactions, from carnivore territoriality to risk analysis related to biological invaders, such as the zebra mussel in the Great Lakes.

When it comes to emerging infectious diseases of wildlife, Dr. Lewis says that public perception and policy needs to move beyond seeing "special cases" to seeing the constant role that people play.

"The way that people often think about emerging infectious diseases is that there are just a lot of special cases. That this happened here and that happened there, without any commonalties," notes Dr. Lewis. "But there’s a growing sense that emerging infectious diseases are really important as a group. So we need the quantitative tools and mathematical theory to be able to study them, including being predictive and diagnostic."

In the case of sea lice, Krkosek, Dr. Lewis and biologist Dr. John Volpe at the University of Victoria, Canada used an innovative live-sampling technique to document the transfer and spreading impact of parasite transmission from a fish farm to wild salmon. "There’s a long and beautiful history of mathematical models for parasite transmission that goes back to the 1970s," Dr. Lewis says. "But the thing that was really unusual here was the spatial structure."

The researchers analyzed the sea lice infection rates of more than 12,000 juvenile wild chum and pink salmon as they headed out to sea from their natal rivers. The infection rates were measured in intervals before and for 60 kilometres after they passed a commercial salmon farm.

"Our research shows that the impact of a single salmon farm is far reaching," says Krkosek. "Sea lice production from the farm we studied was 30,000 times higher than natural. These lice then spread out around the farm. Infection of wild juvenile salmon was 73 times higher than ambient levels near the farm and exceeded ambient levels for 30 kilometres of the wild migration route."

The researchers are now extending their work to assess how this increased parasite load affects the health of the young fish. There’s already initial evidence that this human-induced parasite boost kills many fish. Dr. Rick Routledge from Simon Fraser University and his collaborators recently showed that infection rates similar to those documented by Dr. Lewis will kill juvenile pink and chum salmon.

But, says Dr. Lewis, there’s evidence that some British Columbian salmon farmers aren’t waiting for the final wildlife forensics report to take action. They’re taking the researchers’ sea lice numbers to heart and moving their salmon farms. In an unprecedented agreement, Marine Harvest Canada, a major fish farming company, has agreed to move adult salmon from its farm at Glacier Bay in British Columbia’s Broughton Archipelago to another site further away from a major migration route of emerging wild juvenile salmon.

Says Dr. Lewis: "Ours is basic research, but the mathematical biology clearly gives key results about the contentious issue of fish farm impact on sea lice and wild salmon."

Both Dr. Lewis’ and Marty Krkosek’s research is funded by the Natural Sciences and Engineering Research Council of Canada.

Mark Lewis | EurekAlert!
Further information:
http://www.ualberta.ca
http://www.math.ualberta.ca/~mlewis/index.htm

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>