Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hope is reborn for the European sea sturgeon

26.09.2007
A first release of 3000 European sea sturgeons, Acipenser sturio, took place today in Dordogne, in the Saint-Jean-de-Blaignac / Pessacsur- Dordogne sector, with Madame Nathalie KOSCIUSKO-MORIZET, the Secretary of State for Ecology in attendance.

The Minister then visited the experimental station operated by the Cemagref (Research Institute for Agricultural and Environmental Engineering) at Saint-Seurin-sur-l’Isle (in the Gironde department). She then hailed the work of the researchers, engineers,and technicians who succeeded, on 25 June of this year, the first artificial reproduction of the European sea sturgeon from specimens raised in captivity.

The birth of 11,000 larvae is an important advance in the restoration of this species, part of a programme within the National Strategy for Biodiversity.

Until the 19th century, the European sea sturgeon, Acipenser sturio, inhabited most of Western Europe’s rivers. Today, only a few thousand individuals subsist, all natives of the Gironde. Even though it has been a protected species in France since 1982 and in Europe since 1988, the last population has continued to decline. This successful artificial reproduction compensates for the absence of any reproduction observed since 1994 in Gironde, because returning parents have become rare.

At the hatchery for 3 months, the European sea sturgeon were given attentive care that included following their growth and health. First they were fed day and night with tiny shell fish (Artemia salina), then with sand worms (Chironomus sp.) before they were offered a diversified feed of natural foods (chironomids, mussels, shrimp) completed by artificial foods. Their survival rate was excellent (68% for the overall period) and they currently weigh an average of 3.4 g and are 100 mm long.

Today 7500 young sturgeons are ready to join their natural milieu. A second batch will be released into the Garonne on 24 September in the Meilhansur-Garonne sector. All the fish will have been marked by immersion in a chemical substance that fixes in the bone structures so that they can later be identified.

In addition, two small groups of fish will be preserved in captivity until summer 2008, when they will have reached a sufficient size to be equipped with transmitters and released. This will allow researchers to follow their movements in the rivers and then the estuary to gain knowledge on the habitats the fish go to at this stage of development and thus preserve these areas better.

Finally, 1200 young fish will remain in captivity to reinforce two captive stocks that make up the foundation of the conservation and restoration programme for this zpecies on the European scale: one is situated in France (the Cemagref station in Saint-Seurin-sur-l’Isle) and the other in Germany (Berlin’s Freshwater Institute).

This stock will produce the future parent fish (in a dozen years) on which pursuit of future restoration programmes will depend.

The last successful artificial reproduction dates back to 1995. Obtained at that time with wild parent fish, this programme reinforced the relict population in the natural milieu naturel because 9000 larvae and young fish were released into the Garonne and Dordogne rivers. However, the scarcity of returning wild parent fish made a renewed attempt at reproduction impossible, which explains the strategy of preserving juveniles in captivity over the long term to produce parent fish.

These encouraging results crown more than 25 years of research conducted by the Cemagref and its scientific partners (University of Bordeaux I and Berlin’s Freshwater Institute), both in natural milieu and in captivity. This research has notably been financed by the European Union (LIFE-Nature supported by EPIDOR and Feder), The Ministry of Ecology, the Aquitaine and Poitou-Charentes regions, the Charente-Maritime and Gironde departments, and the Adour Garonne water agency.

This research continues within a national consortium coordinated by WWF France and groups scientific organizations as well as public institutions organized around river basins: EPIDOR (the Dordogne river basin), SMEAG (the Garonne river basin) and SMIDDEST (the Gironde estuary), as well as the CNPMEM (National Committee for Maritime Fisheries and Marine Farming).

Awareness campaigns on the situation of the species, aiming notably at preserving the habitats used by these fish and llimiting the risks in case of accidental capture – indispensable conditions for restoring the population – also benefit from the involvement of local fishermen’s associations, associations for the protection of wildlife, and specific associations for the preservation of sturgeons.

The European sea sturgeon, Acipenser sturio, is indeed a species that is strictly protected by several international agreements (CITES, the Bern agreements) and European directives (fauna, flora, habitat; OSPAR). A plan for preserving the pecies on the European scale is being finalized under the auspices of the Bern agreement.

Hope is being reborn for the Acipenser sturio, whose sufficient numbers in the coming years may make it possible to revive the dynamics of the last population in the world. New perspectives for reintroducing the European sea sturgeon, over time, to other river basins belonging to the historical territory of this species are opened up, subject to the conditions of the milieux, control of the pressures these fish are subjected to (notably from captures) and the will to restore the aquatic biodiversity that is favorable to this type of operation.

Marie Signoret | alfa
Further information:
http://www.cemagref.fr/Informations/Actualites/

More articles from Ecology, The Environment and Conservation:

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

nachricht Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

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

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>