In half of the North Atlantic and North Pacific waters under national jurisdiction, fishing has led to a 90-per-cent decrease in top predators since the 1950s, and the impacts are now headed south of the Equator, according to a new study published online today in the journal Marine Ecological progress Series. The study is available at http://www.int-res.com/abstracts/meps/v442/p169-185/.
Funded by the Pew Charitable Trusts, the Natural Sciences and Engineering Research Council of Canada (NSERC), and the French Consulate-General in Vancouver, researchers from UBC’s Fisheries Centre modeled the impact of fishing around the world using global databases of fisheries catches from 1950 to 2006 and satellite images of phytoplankton, which are used to map where predators should be, based on food availability.
The scientists found that the exploitation of marine predators first occurred in coastal areas of northern countries, then expanded to the high seas and to the southern hemisphere. The decline of top-of-the-food-chain predators also means widespread and fundamental changes to both the structure and function of marine systems.
“Species such as tuna have been seriously exploited because of high market demand,” says Laura Tremblay-Boyer, a PhD student at UBC Fisheries Centre and lead author of the study.
“A constant theme throughout our study of global marine ecosystems is that these top predators are today prey for human beings, assisted by some serious technology,” says Tremblay-Boyer. “Top marine predators are more intrinsically vulnerable to the effects of fishing due to their life histories. Bluefin tuna, for instance, cannot reproduce until age nine.”
In addition to low numbers in the northern hemisphere, the study shows a dramatic decline in the south seas, where wild-caught fish are sent to northern markets.
“After running out of predator fish in the north Atlantic and Pacific, rather than implementing strict management and enforcement, the fishing industry pointed its bows south,” says co-author Daniel Pauly, principal investigator of the Sea Around Us Project at UBC. “The southern hemisphere predators are now on the same trajectory as the ones in the northern hemisphere. What happens next when we have nowhere left to turn?”
Under current fishing practices, biomass loss of predatory species is expected to occur in the southern hemisphere, but humans living in the south will not be able to rely on the north for their fish, the research team adds.
The University of British Columbia Fisheries Centre, in the College for Interdisciplinary Studies, undertakes research to restore fisheries, conserve aquatic life and rebuild ecosystems. It promotes multidisciplinary study of aquatic ecosystems and broad-based collaboration with maritime communities, government, NGOs and other partners. The UBC Fisheries Centre is recognized globally for its innovative and enterprising research, with its academics winning many accolades and awards. For more information, visit www.fisheries.ubc.ca.
The Pew Environment Group is the conservation arm of The Pew Charitable Trusts, a non-governmental organization headquartered in the United States that applies a rigorous, analytical approach to improving public policy, informing the public and stimulating civic life.
Brian Lin | EurekAlert!
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus
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...
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...
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...
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...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Materials Sciences
27.10.2016 | Physics and Astronomy
27.10.2016 | Life Sciences