Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Is 80-year-old mistake leading to first species to be fished to extinction?

19.11.2009
Species of common skate driven into 'irreversible decline'

A species of common skate is to become the first marine fish species to be driven to extinction by commercial fishing, due to an error of species classification 80 years ago, reveals research published today in the journal Aquatic Conservation.

The European common skate, Dipturus batis, has been on the World Conservation Union's Red List of Threatened Species since 2006, with France currently being responsible for 60.2% of reported landings. These catches are predominantly registered under the name 'D.batis,' however researchers, led by Dr Samuel Iglésias, show that 'D. batis' is in fact two clearly distinct species which have been incorrectly categorised as one since the 1920s.

From the mid-19th century the common skate was described as two distinct species, the flapper skate, D. intermedia, and the blue skate, D. flossada. However, in an influential work in 1926 R.S Clark recognised only 'D. batis' as a valid species and this classification has largely gone unchallenged since.

This classification confusion has resulted in the depletion of the flapper skate, the more endangered species of the two, being masked in the catch record. This means the risk of extinction is far higher than previously assessed and without immediate and incisive action the species may be in an irreversible decline towards extinction.

When conducting sampling in fish markets during the start of this study Dr Iglésias observed noticeable morphological differences in the 'Dipturus batis' specimens he sampled. In order to understand these differences the researchers not only analysed the systematic molecular data but also reviewed the species' life history and analysed fishery statistics.

"As the species was listed as 'Critically endangered' I wanted to understand who's who? I estimated at the beginning that it would take some weeks to resolve this question, but in the end it took me about two years," said Iglésias. "Our research clearly shows that D. cf. flossada and D. cf. intermedia are distinct and should be resurrected as two valid species."

Common Skates, which were once abundant in British and European waters, have been in sharp decline for decades. In 2008 the International Council for the Exploration of the Sea (ICES) noted that the species is depleted in the Celtic and North Seas, the Skagerrak and the English Channel. The ICES advised no target fishing and that by-catch should be minimised.

"The threat of extinction for European Dipturus together with mislabelling in fishery statistics highlight the need for a huge reassessment of population for the different Dipturus species in European waters," concluded Iglésias. "Without revision and recognition of its distinct status the world's largest skate, D. cf. intermedia, could soon be rendered extinct."

Ben Norman | EurekAlert!
Further information:
http://www.wiley.com

More articles from Ecology, The Environment and Conservation:

nachricht Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>