Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Gulf of Maine marine ecosystem may have entered new phase


For most of the past 4,500 years, cod was king in the Gulf of Maine’s coastal waters. Today, cod have given way to the Jonah crab with potential long-term consequences for coastal fisheries, according to a University of Maine research report published in the journal Ecosystems.

With crabs and lobsters at the top of the proverbial heap, the Gulf may have entered a new stable phase marked by the presence of expansive kelp beds and the near absence of sea urchins. These findings could signal the likelihood of significant biological changes in other heavily fished parts of the world’s oceans as well.

The authors of the report are Robert S. Steneck, professor of marine sciences at UMaine’s Darling Marine Center, and former UMaine graduate students John Vavrinec and Amanda Leland. They received support for their research from the Pew Foundation for Marine Conservation, Maine Sea Grant, the Maine Department of Marine Resources and the National Undersea Research Program.

The researchers analyzed fishing records and previous studies to gather evidence for the changes brought on by fishing pressure in marine ecosystems. Ancient coastal middens, for example, have revealed evidence suggesting that Native American fishing activities were beginning to affect near shore ecosystems several thousand years ago. Analysis of colonial and modern fish landing records shows that such changes accelerated with the adoption of new fishing technologies.

It is a revolution of sorts, an overturning of the established order brought on by fishing pressure, that leads to major changes in the coastal marine ecosystem, according to the article, "Accelerating Trophic-level Dysfunction in Kelp Forest Ecosystems of the Western North Atlantic." In the Gulf of Maine, the revolution was brought on by the drastic reduction in the number of cod and other top predators over the past century.

"To understand how these changes are accelerating, we looked at archaeological data for coastal Maine over the past 4,500 years. The long dominance of predators has given way to many species playing ’king of the hill,’" says Steneck.

"While there is no fear of these species going extinct," he adds, "entire sections of the food web have become so rare that they no longer perform critical ecological functions in the marine community. This is called food web (or trophic level) dysfunction."

When such species as cod were no longer able to perform their function of keeping their prey species in check, the ecosystem entered a new phase marked by abundant sea urchins and a lack of kelp beds. Urchins ate so much kelp that they created areas known as "urchin barrens" where only low growing algae could survive.

In turn, the harvesting of urchins during the 1990s has led to the re-emergence of kelp beds and the dominance of crabs and lobsters. The report cites an experiment in which adult urchins were stocked in an area to see if they would survive and reproduce. Crabs ate most of the urchins.

"The problem is, this ’trophic level dysfunction’ is accelerating. Ecosystem changes persist for shorter and shorter periods of time because the ’driver’ species increasingly fall below functional population densities," Steneck explains.

"When a threshold is reached, the system changes fundamentally. Everything that came before it is thrown out the window. What this does in the long run is make the system unpredictable."

For the first time, adds Steneck, the low diversity of marine organisms, including Maine’s fabled groundfish, have left the system too reliant on a single species (lobster) and too vulnerable to continued and unpredictable large-scale fluctuations.

Robert Steneck | EurekAlert!
Further information:

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: 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...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

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...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

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

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>