New research led by the University of Southampton is paving the way to protect the endangered European eel as they migrate through rivers to the ocean.
The European eel, a fish of high cultural, commercial and conservation concern, has suffered a dramatic decline over recent decades, with the number of juvenile fish returning to rivers down by over 90 per cent.
While several explanations (including overfishing, pollution and climate change) have been proposed for the cause of this demise, one of the key factors is river infrastructure, such as hydropower stations, that can injure or kill the long bodied adult fish as they migrate to the ocean and eventually to the Sargasso Sea where they spawn.
Because of their long bodies, eels that enter turbine intakes are likely be struck by the rotating blades, causing physical injury and high rates of mortality.
An international collaboration between fish biologists and engineers, led by researchers at the University of Southampton and involving the Environment Agency and the University of Padua in Italy, has now demonstrated the potential to use accelerating water gradients, common at many types of river infrastructure, to influence eel behaviour and produce an avoidance response.
In field experiments, Dr Adam Piper, from the University's International Centre for Ecohydraulics Research (ICER), used acoustic telemetry to track the paths of 40 tagged eels as they approached a hydropower intake site where the speed of water flows were manipulated.
The results of the research, published in the journal Proceedings of the Royal Society B, demonstrated that eels exhibited stronger avoidance when the acceleration of water velocity was greater.
Initially, the eels aligned with streamlines near the channel banks and approached the intake semi-passively. Under normal water velocity, when the eels encountered the constricted flows of the intake, exploratory 'search' behaviour was common prior to coming into physical contact with structures. However, under high water velocity gradients, the eels swam in the opposite direction to escape rapidly back upstream.
Dr Paul Kemp from ICER and the project leader, said: "This interdisciplinary research provides hope that behavioural deterrents may be developed to divert eels away from hazardous routes during their downstream migration."
Glenn Harris | EurekAlert!
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences