New research by scientists at the University of Maryland Center for Environmental Science Chesapeake Biological Laboratory questions the long-held belief that a lack of predators and competitors was the primary cause for the increase of skates and dogfish observed in Southern New England’s George’s Bank following overfishing of commercially important species in the 1980’s.
In an article appearing in the journal Ecological Applications, researchers Michael Frisk, Thomas Miller, Steve Martell and Katherine Sosebee argue that the increase of winter skate on George’s Bank was the result of a migration to the area from adjacent – or connected – waters. This hypothesis challenges the current notion that the Georges Bank’s population is closed and if true, could have significant implications to management of the fishery.
Previously, scientists hypothesized that increased populations of skates and dogfish were the result of less competition from the reduced numbers of commercially important species (including cod, haddock and flounder) normally found in that area. When combined with the belief that the Georges Banks’ skate and dogfish populations were closed – or not connected to populations in adjacent areas – fisheries managers believed that declines in abundance could be offset simply by decreases in fishery harvests
“If the regime shift observed on Georges Bank was driven purely by population dynamics internal to the system, then local management action has the potential to drive the system back to its former state,” said Frisk. “If on the other hand, skate populations in the northwest Atlantic exhibit connectivity, as suggested in our alternative hypothesis, then management of skates must be integrated across the whole northwest Atlantic. Local management actions may be insufficient to alter local abundances. Our research would argue for a broader ecosystem-based approach to fisheries management.”
The concepts Frisk and colleagues put forward also place an emphasis on movement of adults rather than the drift of eggs and larvae as has been typical in research on connectivity among populations.
The research team developed their hypothesis by analyzing survey data collected by the National Marine Fisheries Service and the Canadian Department of Fisheries and Oceans. They found that as winter skate populations on Georges Bank increased, populations appeared to decrease on the Scotian Shelf, some twenty miles away.
Christopher Conner | EurekAlert!
Machine learning helps predict worldwide plant-conservation priorities
04.12.2018 | Ohio State University
From the Arctic to the tropics: researchers present a unique database on Earth’s vegetation
20.11.2018 | Martin-Luther-Universität Halle-Wittenberg
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.
Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...
Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.
Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
12.12.2018 | Health and Medicine
12.12.2018 | Physics and Astronomy
12.12.2018 | Health and Medicine