Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study highlights snowball effect of overfishing

08.01.2014
Florida State University researchers have spearheaded a major review of fisheries data that examines the domino effect that occurs when too many fish are harvested from one habitat.

The loss of a major species from an ecosystem can have unintended consequences because of the connections between that species and others in the system. Moreover, these changes often occur rapidly and unexpectedly, and are difficult to reverse.

“You don’t realize how interdependent species are until it all unravels,” said Felicia Coleman, director of the Florida State University Coastal and Marine Laboratory and a co-author on the study.

Coleman and her co-authors, led by FSU biological science Professor Joseph Travis, examined case studies of several distressed ecosystems that had been thoroughly changed over the years because of overfishing.

For example, in the Northern Benguela ecosystem off Namibia, stocks of sardine and anchovy collapsed in the 1970s from overfishing and were replaced by bearded goby and jellyfish. But the bearded goby and jellyfish are far less energy-rich than a sardine or anchovy, which meant that their populations were not an adequate food source for other sea animals in the region such as penguins, gannets and hake, which had fed on the sardines and anchovies. African penguins and Cape gannets have declined by 77 percent and 94 percent respectively. Cape hake and deep-water hake production plummeted from 725,000 metric tons in 1972, to 110,000 metric tons in 1990. And the population of Cape fur seals has fluctuated dramatically.

“When you put all these examples together, you realize there really is something important going on in the world’s ecosystems,” Travis said. “It’s easy to write off one case study. But, when you string them all together as this paper does, I think you come away with a compelling case that tipping points are real, we’ve crossed them in many ecosystems, and we’ll cross more of them unless we can get this problem under control.”

The full study appears in the Dec. 23 issue of “Proceedings of the National Academy of Sciences. ”

Travis, Coleman and their colleagues are hoping that their research will accelerate changes in how fisheries scientists approach these ecosystem problems and how fisheries managers integrate system issues into their efforts. They hope that more effort will be devoted to understanding the key linkages among species that set up tipping points in ecosystems and that managers look for data that can show when a system might be approaching its tipping point.

“It’s a lot easier to back up to avoid a tipping point before you get to it than it is to find a way to return once you’ve crossed it,” Travis said.

Fishing experts do generally understand how overfishing affects other species and the ecosystem as a whole, but it “needs to be a bigger part of the conversation and turned into action,” Coleman said.

Travis and Coleman were joined in their research by eight other scientists from the University of Connecticut, University of California-Berkeley, University of California-Santa Cruz, University of Chicago, University of North Carolina at Chapel Hill, University of Maine and Centre de Recherche Halieutique Méditerranéenne et Tropicale in France.

Tom Butler | EurekAlert!
Further information:
http://www.fsu.edu

Further reports about: Cape Verde Islands Overfishing domino effect ecosystem snowball effect

More articles from Ecology, The Environment and Conservation:

nachricht Europeans have unknowingly contributed to the spread of invasive plant species in North America
01.07.2015 | Helmholtz-Zentrum für Umweltforschung - UFZ

nachricht Darwin's finches have reached their limits on the Galápagos
23.06.2015 | University of Groningen

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: X-rays and electrons join forces to map catalytic reactions in real-time

New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions

A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...

Im Focus: Iron: A biological element?

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.

Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...

Im Focus: Thousands of Droplets for Diagnostics

Researchers develop new method enabling DNA molecules to be counted in just 30 minutes

A team of scientists including PhD student Friedrich Schuler from the Laboratory of MEMS Applications at the Department of Microsystems Engineering (IMTEK) of...

Im Focus: Bionic eye clinical trial results show long-term safety, efficacy vision-restoring implant

Patients using Argus II experienced significant improvement in visual function and quality of life

The three-year clinical trial results of the retinal implant popularly known as the "bionic eye," have proven the long-term efficacy, safety and reliability of...

Im Focus: Lasers for Fast Internet in Space – Space Technology from Aachen

On June 23, the second Sentinel mission was launched from the space mission launch center in Kourou. A critical component of Aachen is on board. Researchers at the Fraunhofer Institute for Laser Technology ILT and Tesat-Spacecom have jointly developed the know-how for space-qualified laser components. For the Sentinel mission the diode laser pump module of the Laser Communication Terminal LCT was planned and constructed in Aachen in cooperation with the manufacturer of the LCT, Tesat-Spacecom, and the Ferdinand Braun Institute.

After eight years of preparation, in the early morning of June 23 the time had come: in Kourou in French Guiana, the European Space Agency launched the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

World Conference on Regenerative Medicine: Abstract Submission has been extended to 24 June

16.06.2015 | Event News

MUSE hosting Europe’s largest science communication conference

11.06.2015 | Event News

 
Latest News

Offshore wind park Westermost Rough officially inaugurated

01.07.2015 | Press release

Siemens Velaro train wins "Red Dot" award

01.07.2015 | Awards Funding

Liquids on Fibers - Slipping or Flowing?

01.07.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>