Impaired recovery of Atlantic cod -- forage fish or other factors?

April 30, 2012

In a rapid communication just published in the Canadian Journal of Fisheries and Aquatic Sciences, biologist Douglas Swain of the Gulf Fisheries Centre and Robert Mohn, emeritus scientist, at the Bedford Institute of Oceanography present findings that suggest the delay in recovery of Atlantic cod on the eastern Scotian Shelf could be attributed to increased predation by grey seals or other governing factors and not the effect of forage fish as previously thought.

"Swain and Mohn provide provocative scientific evidence challenging the commonly held belief that species interactions with forage fish have impaired the recovery of Atlantic cod on the eastern Scotian Shelf during the 15-year fishing moratorium," says Rolf D. Vinebrooke, Co-editor of the Canadian Journal of Fisheries and Aquatic Sciences. "They report a lack of a direct relationship between forage and cod recruitment rates, suggesting that density-dependent effects of competition and predation by cannot therefore account for lack of recovery by cod stocks. Most importantly, their data show that the lack of resilience stems from as of yet unidentified factors affecting high death rates among adult cod."

The authors conclude that further investigation is required to ensure proper understanding and appropriate management to improve the chances for recovery of stocks.

Explore further: British cod stocks rebounding

More information: Canadian Journal of Fisheries and Aquatic Sciences. 69(6) doi: 10.1139/F2012-045

Related Stories

British cod stocks rebounding

October 22, 2007

Researchers say cod stocks around Britain have rebounded enough to permit small catches in the North Sea, The Times of London reported Saturday.

US Atlantic cod population to drop by half by 2050

February 12, 2009

A University of British Columbia researcher put a number to the impact of climate change on world fisheries at today's Annual Meeting of the American Association for the Advancement of Science (AAAS) in Chicago.

Cod resurgence in Canadian waters

July 27, 2011

Cod and other groundfish populations off the east coast of Canada are showing signs of recovery more than 20 years after the fisheries collapsed in the early 1990s, according to research published today in Nature.

Recommended for you

How bees naturally vaccinate their babies

July 31, 2015

When it comes to vaccinating their babies, bees don't have a choice—they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how ...

New insights into the production of antibiotics by bacteria

July 31, 2015

Bacteria use antibiotics as a weapon and even produce more antibiotics if there are competing strains nearby. This is a fundamental insight that can help find new antibiotics. Leiden scientists Daniel Rozen and Gilles van ...

Out of the lamplight

July 31, 2015

The human body is governed by complex biochemical circuits. Chemical inputs spur chain reactions that generate new outputs. Understanding how these circuits work—how their components interact to enable life—is critical ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.