Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fewer fish discarded after individual transferable quotas offered

29.03.2005


Contradicting previous assumptions, new fisheries research shows that allocating catch among vessels reduces the amount of fish discarded at sea.



The study in Canada’s British Columbia waters compared so-called individual transferable quotas with a previously used system of trip limits where vessels are only allowed to land a certain quantity of each species every two months.

The findings come at a time when individual transferable quotas are being considered for the west coast of the United States. "Economic models have assumed all along that individual transferable quotas increase discards," says Trevor Branch, who earned his doctorate in aquatic and fishery sciences at the University of Washington and is lead author of an article published online this week by the journal Marine Policy.


But discards did not increase – they declined for most species, report Trevor and co-authors Kate Rutherford, biologist with Fisheries and Oceans Canada in British Columbia, and Ray Hilborn, UW professor of aquatic and fishery sciences.

The study, "Replacing Trip Limits with Individual Transferable Quotas: Implications for Discarding," is the first to look at 35 species instead of only a handful, or even just a single species, before and after quotas were implemented.

With individual transferable quotas, the total allowable catch is divided among a limited number of boats with each quota holder receiving a specific proportion of the total catch. Quota holders then decide how and when to fish, and whether to buy additional quotas or lease or sell their quotas.

Such a system was implemented in British Columbia waters in 1997, after a one-year transition from individual trip limits and overall caps on the fleet. After a period of adjustment, rates have remained generally similar or even less than the 15 percent of fish discarded in 1996.

Discarding occurs when, for example, unmarketable fish are caught or where trip limits are imposed and once the maximum of a certain fish is caught, all the rest of that type of fish that is caught must be discarded.

Trip limits are used in U.S. waters to protect overfished stocks and they have proved effective, Branch says. "It’s just that perhaps the mortality could have been reduced just as much under individual transferable quotas and without discarding large amounts of marketable fish, an economic loss for fishers that is hard to estimate," he says.

Under British Columbia’s individual transferable quota system, for instance, skippers have had more flexibility to choose when, where and how to fish so fewer small, unmarketable fish were caught. Then too, skippers with more than their quota of a certain kind of fish could try to arrange to lease or buy another’s quota to cover the overage.

Other differences between the two systems include full mortality accounting in the British Columbia fishery – meaning any marketable fish that was discarded at sea was deducted from the amount the vessel was allowed to bring to shore – and the presence of observers on every boat. In the U.S. West Coast fishery, there is no deduction when marketable fish are discarded and in recent seasons monitors were on board 13 to 16 percent of the vessels.

In comparing the two fisheries, the researchers found British Columbia discard rates of 14 percent and 19 percent in two recent fishing seasons, compared with 43 percent and 31 percent for those same seasons in U.S. West Coast waters – the drop to 31 percent partly because new Groundfish Conservation Areas put some fishing grounds off limits, the scientists note. Which animals live once returned to the sea depends on the organism; for instance, species of rockfish all tend to die while lingcod and sablefish are among the fish with better survival rates.

"This research is interesting because it dramatically illustrates how discarding practices are influences by the regulation system," Branch says. "In the British Columbia fishery, individual transferable quotas combined with 100 percent observer coverage reduce discard rates of marketable fish to negligible amounts, whereas trip limits imposed on U.S. West Coast fishers force them to discard fish over their limits resulting in high discard rates."

Even if the United States started using a system similar to that in British Columbia, the challenge of dealing with overfished species may mean U.S. fisheries may never have discard rates as low as those of British Columbia, the authors say.

Such a change also would involve the cost of 100 percent observer coverage, although the authors write the costs may be outweighed by the benefits. "In many ITQ [individual transferable quotas] fisheries, increased profitability enables on-board observers to be funded from cost-recovery programs, increased retention of marketable fish would usually increase the profits of fishers and there may be considerable economic value attached to more accurate and reliable stock assessments."

Branch, who earned his doctorate from the UW with funding from the South African National Research Foundation and the U.S. National Marine Fisheries Service, is currently conducting marine assessment and management research at the University of Cape Town, South Africa.

Sandra Hines | EurekAlert!
Further information:
http://www.washington.edu

More articles from Ecology, The Environment and Conservation:

nachricht Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>