Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Extreme winters impact fish negatively

14.02.2013
Ecologists from Umeå University and the Norwegian University of Science and Technology in Trondheim have studied fish communities and the living environments of fish and put together a compilation of the importance of winter conditions for fish in streams and rivers in cold regions. The findings are now being published in the journal BioScience.

It is well known that winter can be a stressful season for plants and animals in streams and rivers. It is reasonable to assume that it is the more extreme weather conditions that are the most taxing, but the ecological significance of this is poorly understood.


It is difficult to be a fish when the bottom of the river is covered with ice. Winter image from the river Orkla in Norway. Photo: Knut Alfredsen

The research team, headed by Professor Christer Nilsson at Umeå University, describes how extreme conditions – especially those associated with ice formation and ice break-up – vary over time and affect both the non-living environment and its fish. For example, waterways can fill up with ice and kill all fish that do not manage to flee to backwaters or deeper stretches of quiet water that is not filled with ice. Young fish are especially vulnerable.

The researchers also discuss how humans have impacted what happens in streams and rivers in the winter.

“Rivers that have been exploited for hydroelectric power can be especially hard for fish to live in, because the way hydropower is produced often means that the flow is radically changed again and again, which can lead to repeated ice break-ups and a great deal of bottom ice formation. When the ice cover at the surface disappears, cold air is fed downward in the water and forms ice crystals that cover the bottom, making it hard for fish to survive,” says Christer Nilsson.

The scientists draw a number of conclusions from the study. One is that more measurements are needed in order to be able to predict when extreme situations in waterways may arise and that information about both the lives of different fishes and how they are affected by extreme events should be included in such data gathering. Another is that models of how water moves and what fish populations look like should also take winter conditions into consideration.

Today most models are about the ice-free period. A third conclusion is that in order to be able to manage streams and rivers in a long-term sustainable manner, we need to pay attention to future changes in climate, for example, when we design restoration and conservation measures.

“The predictions made about what the winter climate will be like in the future say that there will be more back and forth between thaw and frost, entailing more unstable ice conditions, more rain, and flooding, and ultimately perhaps more challenges to the survival of fish in many waterways,” says Christer Nilsson.

Original publication:
The article will be published in the March issue of BioScience
Weber, C., C. Nilsson, L. Lind, K.T. Alfredsen & L.E. Polvi. 2013. Winter disturbances and riverine fish in temperate and cold regions. BioScience 63:199-210. doi:10:1525/bio.2013.63.3.8.
For more information, please contact:
Christer Nilsson, Department of Ecology and Environmental Science, Umeå University, Phone: +46 (0)90-786 60 03, E-mail: christer.nilsson@emg.umu.se

Ingrid Söderbergh | idw
Further information:
http://www.umu.se

Further reports about: BioScience fish population ice crystal ice formation

More articles from Ecology, The Environment and Conservation:

nachricht Minimized water consumption in CSP plants - EU project MinWaterCSP is making good progress
05.12.2017 | Steinbeis-Europa-Zentrum

nachricht Jena Experiment: Loss of species destroys ecosystems
28.11.2017 | Technische Universität München

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: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>