FRCC Submission re 3Ps Cod

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Effective Date: January 15, 2001

The Stock Status Report and other available information with respect to 3Ps cod have once again left the FRCC with an unenviable decision to make in 2001. One of the real dangers facing those who depend on this resource is that there will be an over reaction to the latest SSR, particularly since the change in model formulation is so critical to the outcome.

The SSR describes the spawning stock biomass as being "comparable to the SSB in 1992 just before the 1993 moratorium", but the basis for the calculation is quite different. If the current calculation were done on the same basis as the 1992 calculation, the result would be quite different. Conversely, the 1992 biomass estimate generated by the new formulation produces a biomass in the range of 52,000 m.t., compared to 76,000 m.t. for 2001.

To put it bluntly, we have little or no confidence in the latest SSB estimate. The output of a mathematical model is driven by often subjective decisions about inputs. In this particular case, conclusions concerning mixing of stocks and the ensuing decision to change the treatment of survey data from Burgeo Bank and Hermitage Channel led to very significant changes in the assessment of the size of the stock.

We question whether the facts justify such a decision as to treatment of the data. The variations in fish behaviour in 3Ps both from year to year and also within years are well known. For example, while the 1998 tagging in Burgeo Bank/Hermitage Channel resulted in significant recapture in 4RS3Pn, this was not the case in 1999, when tagging in April gave rise to recapture primarily within 3Ps during the 1999 fishery. Evidence as to the timing and extent of mixing is inconclusive, yet mixing is the rationale for a significant change in model formulation that dramatically affects the biomass estimate (reduction of approximately 40,000 m.t.).

Back in 1993, the RV survey was moved from February to April to avoid the mixing with Gulf stocks that was clearly a problem on the Burgeo Bank in February. The only rationale given for the decision to separate the Burgeo Bank/Hermitage Channel stock component in the latest SSR was the outcome of a 1998 tagging study, the results of which were entirely different from a similar study in 1999. It appears quite likely that 1998 was an anomalous year with respect to mixing.

The FRCC would do well to recall the following comment from its 1999 advice with respect to 4RS3Pn cod:

"The Council also is reluctant to recommend major year-over-year fluctuations in TAC's in response to biomass estimates which vary significantly on an annual basis due primarily to revised formulations of the Virtual Population Analysis (VPA)."

3Ps cod is clearly a troublesome, unpredictable stock to try to assess. The FRCC reflected this concern in its 2000 advice on this stock, when its recommended TAC was lower than what the SSR seemed to point to - a decision that, with hindsight, looks quite sound. In a sense, the FRCC anticipated in its 2000 advice some of the problems associated with this year's assessments, and a 10,000 m.t. quota reduction was the result.

On the face of it, the various indicators of this stock have been inconsistent since the moratorium. Inshore, problems of high bycatches of cod were widespread from 1994-97, and sentinel catch rates from 1995-97 were high by any standard, yet offshore research surveys up to and including April 1996 were low and the SSRs around that time had the biomass at or near all-time lows.

Beginning with the April 1997 survey, the SSRs became more positive. RV catches were up, and distribution of cod throughout the survey area began to improve. Commercial catches offshore - both fixed and mobile - were high, but inshore commercial and sentinel catch rates declined noticeably from 1998 - 2000.

Are these inconsistent results or are they simply a reflection of a change in migration and distribution of the stock?

Fortunately, at a time of considerable uncertainty, an additional significant information source will soon be available. The November GEAC survey of the offshore St. Pierre Bank area, begun in 1997, has just been conducted for the forth time, and the results will be available shortly.

Recommendations:

1. The SSR advice is largely driven by debatable conclusions concerning mixing which gave rise to a fundamental change in model formulation. In light of the inconclusive nature of the basis for this decision, the FRCC should incorporate the results of the November GEAC survey, which now has a four-year time series, into its decision-making process.

2. The 3Ps fixed gear cod fishery has changed appreciably from the pre-moratorium fishery which incorporated traps, gill nets and hook and line. As a step toward returning to a more traditional gear deployment, we propose that the FRCC recommend research by DFO into selectivity of cod traps, including research into possible exclusion devices to minimize the catch of small fish.

3. There are some important management issues that are at least as important as the TAC level for 3Ps cod. These include concerns about excessive effort in the Woody Island area as well as the conduct of the St. Pierre Bank fishery. These should be highlighted for the attention of DFO management and specific measures developed through consultation between DFO and industry.

4. There must be some alternative to 10,000 m.t. annual adjustments in the TAC for 3Ps cod. We believe that in conjunction with management measures to deal with the above-noted issues, a rollover of a 20,000 m.t. TAC is appropriate.

5. The FRCC's stated desire for a longer-term management plan has merit. However, the mixing debate needs to be clearly resolved and the GEAC survey fully incorporated before decisions can be made for a prolonged period.