, Gloucester, MA

December 13, 2011

Variables abound in cod study

By Nancy Gaines

The new, grim government head count of local cod — which could, at worst, essentially outlaw the iconic catch — is based on factors that, as with all things fish, are inexact at best.

Built-in variables for the measurement — in stark contrast to fishermen's reports over the past three years of waters teeming with cod — could add up to a conclusion that just isn't so, some scientists say.

For one, the boats used to catch the fish for the scientific model in this and the previous study were different in many key respects that could affect the results. Also, the landings used to extrapolate the number of fish in the sea were based on catches limited by new regulations.

On the other hand, numerous local day boat fishermen have complained over the past months that large trip boats with no official observers aboard had in effect been pillaging Stellwagen Bank. There are also reports from fishermen that unusually large amounts of cod spawn have been found in the bellies of herring.

The anomalous assessment of the health of the cod stock in the Gulf of Maine (Cape Cod north to Nova Scotia), based on a report released last week by the federal New England Fisheries Management Council, reverses the optimistic report from a benchmark study released in 2008.

If the results are reliable, it could mean the death rate of cod is five times the definition of overfishing, said Steve Cadrin of the National Oceanic and Atmospheric Administration (NOAA) in Woods Hole, who participated in the study.

A subcommittee of the fish council will develop a recommendation for consideration at its meeting next month.

"Do I believe the numbers? In a word, no," said David Goethal, a New Hampshire fisherman, biologist and member of the regional fisheries council.

"I'm in the midst of preparing for NOAA an analysis that contradicts their incredible numbers. For example," said Goethal, "I can document I caught more fish in a few days than they say exist."

Speaking at a meeting of fishermen, scientists and regulators in Portsmouth, N.H., last Friday — a special meeting convened in the wake of the findings — NOAA fisheries head Eric Schwaab said "the numbers are so bad and the implications to the fisheries so significant," the government might have to rethink its guidelines.

Under current law, cod stock must be fully restored by 2014. The dramatic, unexpected reversal would mean that the deadline could not be met even if all cod fishing were halted now, according to the findings..

The different government-sanctioned boats conducting the counts recently (the Bigelow) and three years ago (the Albatross), prompted scientists to go "to great lengths to caution fishermen that catches between the two vessels are not directly comparable," according to a June 2010 report in Commercial Fisheries News, citing Russell Brown, chief of the Northeast Fisheries Science Center's Ecosystems Surveys Branch.

"They say practically everything about the whole trawl survey process — from the gear to the towing speed — is now different," the report indicated.

For one, the new boat cannot go into shallow waste, where cod can prevail. Two New England companies who worked together to design and build trawling gear for the $54 million state-of-the-art Bigelow said in a published report last year that the ship's nets were too small, which could affect survey results of groundfish.

If NOAA suspected an error in the comparative methodology, said Brian Rothschild, lead scientist at the School of Marine Science and Technology at the University of Massachusetts Dartmouth, why was no corrective action taken?

"On average, the Bigelow is about 60 percent more efficient at catching cod than the Albatross," said Teri Frady of NOAA. "Anticipating the transition from the Albatross to the Bigelow, during 2008, we conducted one of the largest calibration experiments ever undertaken between fishery survey vessels."

As a side note, said Frady, "the unconverted Bigelow survey values show the same downward trend in Gulf of Maine cod as the converted survey values in 2009 and 2010."

Yet, it's an imprecise science, scientists and fishermen say. Dating back a decade, fishermen have distrusted the population counts.

In an oft-cited episode called "Trawlgate," faulty equipment used by NOAA in 2002 turned out to have gravely underestimated the fish and enraged fishermen, yet the agency stuck with the data to set its regulatory guidelines because it was essentially the only data it had.

While the report was being readied for release, NOAA's Cadrin conceded last week that the assessment was still largely guesswork.

As for the commercial landings — also used in the model to calculate the number of cod — those were allowable portions of a "hard catch" limit, based on the previous year's catch.

As such, the landings were designed by the government to be smaller than in previous years.

Correspondent Nancy Gaines co-authored the Times' 2010 special series, "Fishery Under Siege." She is a veteran reporter and editor for Boston and national publications.