Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Radio-tracking associated with ’dramatic shift’ in water vole sex ratio

03.03.2005


Wildlife researchers are being warned that radio-tracking could be affecting the animals they are studying. According to new research published today in the British Ecological Society’s Journal of Applied Ecology, fitting radio-collars to water voles was associated with a "dramatic shift" in the sex ratio of the animals’ offspring, casting doubt on the assumption that radio-tracking does not fundamentally affect the biology of radio-collared water voles.



The water vole (Arvicola terrestris) is an endangered species in the UK, and ecologists Dr Tom Moorhouse and Professor David Macdonald of Oxford University’s Wildlife Conservation Research Unit had been monitoring the size of two populations - one in Norfolk and one Wiltshire - when they noticed a 48% decline in the number of females born at the Norfolk site. At both sites vole numbers had been monitored using small traps baited with apple and carrot during 2002 and 2003, voles being released after counting. However, Moorhouse and Macdonald had also fitted radio-collars to 38 of the voles caught at the Norfolk site for in-depth study of the voles’ movements.

According to Moorhouse and Macdonald: "Our analysis revealed that the most likely cause for the female decline was a shift in the sex ratio of young raised by radio-collared females. This result has implications for conservation research, especially for monitoring water vole populations."


Skewed sex ratios have been reported in stressed and malnourished females of various species, including water voles. The ecologists suggest this could be explained in terms of the local resource competition hypothesis, which predicts that mothers with access to poor resources will produce offspring of the sex most likely to disperse and therefore reduce local competition for resources. "Radio-collars clearly have the potential to cause some stress to water voles, and it is possible that this might stimulate sex-ratio adjustment as part of an evolutionary mechanism mitigating impacts of suboptimal habitats, similar to the sex-ratio bias and stress response in food deprived water voles," they say.

Researchers have long been aware that the techniques they use had the potential to cause unexpected effects, and there have been many studies into the effects of radio-collars. However, this is the first study to show an association between radio-collars and sex ratio, although further work is needed to establish a causal link. According to Moorhouse and Macdonald: "We would expect any such effect to be species-specific, but our results will alert those studying other small mammals to look for similar associations. Our findings are a reminder that the assumption that the use of radio-collars does not fundamentally affect the biology of the subjects always requires careful checking. This study emphasises that the effects of commonplace wildlife marking and tracking techniques may be difficult to detect and yet both important and revealing. Clearly, it is both scientifically and ethically important to be aware of, and to strive to minimise, any such effects."

Lynne Miller | EurekAlert!
Further information:
http://www.blackwellpublishing.com

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

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: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

CCNY physicists master unexplored electron property

26.07.2017 | Physics and Astronomy

Molecular microscopy illuminates molecular motor motion

26.07.2017 | Life Sciences

Large-Mouthed Fish Was Top Predator After Mass Extinction

26.07.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>