Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists and Fishermen Join Forces to Track Celtic Sea Cod

19.11.2008
A joint project between the Irish fishing industry and scientists from the Marine Institute in Galway to track stocks of cod in the Celtic Sea is starting to yield interesting results.

Funded with monies administered under the Bord Iascaigh Mhara (BIM - the Irish Sea Fisheries Board) National Development Plan over the last two years, 4,063 cod have been tagged and released in the Celtic Sea by Institute scientists working aboard commercial fishing vessels from Dunmore East. The project is designed to study the growth and migration of both the inshore juvenile component and the offshore adult spawning component of the stock.

“To date around 10% of the tagged fish have been returned by a combination of fishermen, anglers and processors from Ireland, UK, Spain and France,” said Macdara Ó Cuaig, a scientist with the Fisheries Science Services team of the Marine Institute. “What makes this project such a success is that every fish that is recaptured and reported adds its own piece of information to the jigsaw and helps us get a better understanding of the stock. This start-stop data is helpful in understanding the behaviour of the fish but does not provide information on where the fish has been at in between. To inform us on the fish activity in-between release and recapture a number of large fish (>50cm) were fitted with an electronic tag.”

These electronic Data Storage Tags (DTS tags), are surgically inserted into the gut cavity of the fish. The tags record time, temperature and depth of the environment surrounding the fish while it is at sea. Each DST tag deployed to date has been set to measure temperature and depth every four minutes for a period of up to two years. Once retrieved, they can yield valuable information about the behaviour of the fish over time by comparing the data recorded by the DST with known temperature and depth data for the area. This allows the scientists to calculate where the fish has been between the release and recapture position, which in turn builds an accurate picture of the migration patterns and associated growth of the stock.

“While the recapture of DST tagged cod to date has provided some interesting data, the amount of information can be limited if the fish is recaptured shortly after release,” explains Macdara. “However, a fish reported to us last month with a conventional tag not only confirmed the rapid growth associated with Celtic Sea cod, but also has the unique distinction of being caught three times and released twice. This fish was originally released in Waterford Estuary on the 6th May 2007 when he was 23 centimetres long with an estimated weight of 120g. He was then caught and released again around St Patrick’s Day this year by our tagging vessel up river above Dunmore East. At that time the fish was 47 centimetres long and weighed over a kilo. He was finally caught and reported by a local on the 26th August at a length of 56 centimetres, weighing a hefty 1.9 kilos, sixty miles south of Hook Head.”

The fact that this fish had grown 33 cm in fifteen months highlights the fact that Celtic Sea cod have high growth rates—in this case an almost nine-fold increase in weight in the first ten months since its initial release, followed by a slower but still significant increase over the next five months to 1.9 kilos.

“This fish had a total of a sixteen-fold increase in weight in just fifteen months!” said Macdara. “This demonstrates the potential yield possible from the Celtic Sea cod stock.”

The Marine Institute and its partners would like to thank all who have reported tagged fish to date and ask that everyone handling cod keep a sharp lookout for tagged fish. Every fish returned has a story to tell and carries a reward as detailed below. The external tag is attached to the first dorsal fin. On spotting a tagged fish the fish should be kept whole. Fish with tag still attached should be stored UNGUTTED on ice/frozen.

The Marine Institute is offering a reward for the return of tagged cod as detailed below:

€100 per Cod returned with High Reward Tag still attached and capture details complete.

€10 per Cod returned with Standard Tag still attached and capture details complete.

Once contacted, arrangements to collect the fish will be made by Marine Institute staff.

Fishermen wishing to return tags should contact:

Macdara Ó Cuaig, Fisheries Scientist, FSS, Marine Institute
Rinnville, Oranmore, Galway.
Phone: 353 91 387200
Mobile: 353 87 207 5988

John Joyce | alfa
Further information:
http://www.marine.ie

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

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: Why we need erasable MRI scans

New technology could allow an MRI contrast agent to 'blink off,' helping doctors diagnose disease

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

World's smallest optical implantable biodevice

26.04.2018 | Power and Electrical Engineering

Molecular evolution: How the building blocks of life may form in space

26.04.2018 | Life Sciences

First Li-Fi-product with technology from Fraunhofer HHI launched in Japan

26.04.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>