Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Study highlights snowball effect of overfishing

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:

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

More articles from Ecology, The Environment and Conservation:

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

nachricht Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus

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: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Steering a fusion plasma toward stability

28.10.2016 | Power and Electrical Engineering

Bioluminescent sensor causes brain cells to glow in the dark

28.10.2016 | Life Sciences

Activation of 2 genes linked to development of atherosclerosis

28.10.2016 | Life Sciences

More VideoLinks >>>