Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bird flu: the wildfowl trail

02.04.2007
How does the highly pathogenic bird flu virus spread to new countries? Might the domestic bird trade be responsible? Or is it wildfowl? Since last year, a team from CIRAD has been working on wildfowl.

To date, the virus has not been detected in healthy wild birds, but many dead or dying birds have been found near infection foci. Are they victims or reservoirs? In all likelihood the former, but the latter hypothesis cannot be ruled out. Six healthy ducks carrying the virus - out of a total of 4600 tested and in a particularly severely infected zone - were found in China in January 2005.

Determining the number of stages and where birds stop off during migration

In 2005 and 2006, migrating birds were often under suspicion. However, their migration corridors and periods did not necessarily correspond to the virus spread patterns seen in recent years. To clarify matters, researchers are now plotting comprehensive, accurate flight plans. To this end, with FAO funding, they are fitting birds with small Argos transmitters. This equipment will provide a large number of data and fill the gaps in information on the subject. Migration has already been studied in detail in Europe and Asia, but this is far from the case in Africa, where monitoring is limited to counting the populations in each country or ringing birds, despite the fact that some five million ducks from Eurasia winter in Subsaharan Africa and there are more than four million African ducks that fly between the different regions of the continent.

In particular, the transmitters will provide information on the number of migration stages and where the birds stop off during migration. In fact, they stop off in humid zones propitious to pathogen transmission, where the different species mix with one another. The study should also provide more general information on migration: travelling times and the ecological and manmade factors that determine the stops.

Three species in three African countries

Three species were chosen for the operation: the blue-winged teal, fulvous whistling duck and comb duck, each of which represents a typical migration route. The teal is a Europe-Asia-Africa intercontinental migrator and winters exclusively in Subsaharan Africa, where it is the most common wintering bird. The comb duck restricts its movements to Africa, but covers several regions, while the fulvous whistling duck, the most common African duck, is a nomadic species on a regional level. The researchers' first step was to test the impact of the transmitters on the birds' behaviour in captivity at Montpellier's Lunaret Zoo. They then travelled to Africa, and captured and equipped 45 birds in February. Captures were made at three sites: northern Nigeria, a very humid zone where there have been bird flu foci for more than a year; the inland delta of the Niger River, in Mali, which is the biggest wintering site for Eurasian ducks in Africa; and Malawi, which had the necessary sites for a study of interregional migration. Now that the birds have been released, they can be monitored, and the results, updated twice weekly, are now available on a CIRAD website: http://wildbirds-ai.cirad.fr.

On-line maps for real-time monitoring

The study is a first for Africa. Teams from the FAO and the United States Geological Survey, which work with CIRAD, have also equipped swans in China and Mongolia. For the time being, the researchers do not know how long the transmitters will continue to supply data (this depends on the birds' lifespan).

Each transmitter weighs between 12 and 30 grammes. The 12- and 18-gramme ones are used for teals and fulvous whistling ducks, and the 30-gramme ones for comb ducks, which are larger. They are fitted to the body of each bird, like small backpacks, using teflon straps. The location of each bird is determined using the Argos system. The transmitter emits a signal that is picked up by satellites in polar orbit at a height of 850 km. The satellites then send the signal back to terrestrial reception stations. The data received are subsequently processed by centres specializing in the Argos system. Lastly, once processed, the data are passed on to users.

The maps available on the Wild birds and avian influenza in Africa website can be used to monitor bird movements, virtually in real time. At the moment, the teals from Nigeria are moving towards Lake Chad. They should be heading north in the next few days.

Helen Burford | alfa
Further information:
http://www.cirad.fr/en/actualite/communique.php?id=667

More articles from Agricultural and Forestry Science:

nachricht Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

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...

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

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>