Habitat and Biology
Depth zone: Shelf (50 m - 200 m). Vertical distribution: Pelagic.
Jurisdictional distribution: National
Water Area Overview
Spatial Scale: Sub-Regional
Considered a single stock: Yes
Factors affecting the fisheries and the stock
Presently the fishery is closed. Usually the fisheries for anchovy are targeted by trawlers and purse-seiners. The Spanish and French fleets fishing for anchovy in Subarea VIII are spatially and temporally well separated. The Spanish fleet operates mainly in Divisions VIIIc and VIIIb in spring, while the French fleets operate in Division VIIIa in summer and autumn and in Division VIIIb in winter and summer. Impacts of the environment on the fish stock
Anchovy is a prey species for other pelagic and demersal species, and also for cetaceans and birds.
Although recruitment depends strongly on environmental factors, recruitment predictions based on environmental variables are not yet sufficiently accurate to estimate the population one year in advance.
MethodologyScientific basisData and methodsA two-stage Bayesian biomass dynamic model (BBM) assessment was used, based on the Daily Egg Production Method (DEPM) (survey since 1987), acoustic surveys (since 1989) and catches from the French and Spanish fisheries.
The assessment method is consistent with that used last year. Uncertainties in assessment and forecast
This year the assessment indicates a reduction of SSB (by about 20 %) despite the apparent stability in the survey SSB estimates. The low fraction of age 1 in both surveys, both in 2008 (implying a low estimate of age 2 in 2009) and in 2009 implies the small drop in SSB suggested by the model.
The current assessment is mainly driven by inputs provided by the surveys (SSB and proportion of 1-group). For the DEPM survey, uncertainties include the assumed spawning frequency (which is under revision) and the daily mortality rate of egg. For the acoustic estimate, even though commercial vessels were used during the survey to explore the coastal area, there may still be problems with the coverage of coastal areas where age 1 dominates. The main uncertainties of the model are that the growth and natural mortality of anchovy are assumed independent of age. Similarly,
there is no age differential catchability in the surveys.
The assumption that DEPM survey data measures the spawning biomass in absolute terms might also increase uncertainty. Stock assessment modelling results do not reflect the additional uncertainty stemming from these factors.The current model provides an estimate of the precision of the results and these are translated into risk that can be included in harvest rules. The 95% credibility intervals indicate that SSB in 2009 is between 15 and 32 thousand tonnes. The uncertainty in recruitment and harvest rate is relatively low. There is also low uncertainty about the current state of the SSB which is among the lowest in the time-series starting in 1987.Comparison with previous assessment and advice
The assessment results are consistent with last year. The perception of the stock and the advice are unchanged.
SSB in 2008 has been revised upwards by 9% compared to last year.
Overall Assessment Results
|Figure 22.214.171.124 Anchovy in Subarea VIII (Bay of Biscay). Catches (in tonnes). |
|Figure 126.96.36.199 Anchovy in Subarea VIII (Bay of Biscay). Posterior median (solid line) and 95% credible intervals (dashed lines) for the recruitment series (top panel, in tonnes), the spawning-stock biomass (middle panel, in tonnes), and the harvest rates (Catch/SSB, bottom panel) from the BBM. |
|Figure 188.8.131.52 Anchovy in Subarea VIII (Bay of Biscay). Distribution of SSB in 2010 constructed from the posterior distribution of SSB in 2009 and the recent years recruitment scenario in the absence of fishing. The vertical dashed line represents Blim (21 000 t). |
|Figure 184.108.40.206 Anchovy in Subarea VIII (Bay of Biscay). Comparison of current assessment for SSB with previous assessments. |
Anchovy in Subarea VIII (Bay of Biscay). Annual catches (in tonnes) (Subarea VIII) as estimated by the Working Group members.
Table 220.127.116.11 Summary of the assessment
|Year ||France |
Live Bait Catches
|1960 ||1,085 ||57,000 ||n/a ||58,085 |
|1961 ||1,494 ||74,000 ||n/a ||75,494 |
|1962 ||1,123 ||58,000 ||n/a ||59,123 |
|1963 ||652 ||48,000 ||n/a ||48,652 |
|1964 ||1,973 ||75,000 ||n/a ||76,973 |
|1965 ||2,615 ||81,000 ||n/a ||83,615 |
|1966 ||839 ||47,519 ||n/a ||48,358 |
|1967 ||1,812 ||39,363 ||n/a ||41,175 |
|1968 ||1,190 ||38,429 ||n/a ||39,619 |
|1969 ||2,991 ||33,092 ||n/a ||36,083 |
|1970 ||3,665 ||19,820 ||n/a ||23,485 |
|1971 ||4,825 ||23,787 ||n/a ||28,612 |
|1972 ||6,150 ||26,917 ||n/a ||33,067 |
|1973 ||4,395 ||23,614 ||n/a ||28,009 |
|1974 ||3,835 ||27,282 ||n/a ||31,117 |
|1975 ||2,913 ||23,389 ||n/a ||26,302 |
|1976 ||1,095 ||36,166 ||n/a ||37,261 |
|1977 ||3,807 ||44,384 ||n/a ||48,191 |
|1978 ||3,683 ||41,536 ||n/a ||45,219 |
|1979 ||1,349 ||25,000 ||n/a ||26,349 |
|1980 ||1,564 ||20,538 ||n/a ||22,102 |
|1981 ||1,021 ||9,794 ||n/a ||10,815 |
|1982 ||381 ||4,610 ||n/a ||4,991 |
|1983 ||1,911 ||12,242 ||n/a ||14,153 |
|1984 ||1,711 ||33,468 ||n/a ||35,179 |
|1985 ||3,005 ||8,481 ||n/a ||11,486 |
|1986 ||2,311 ||5,612 ||n/a ||7,923 |
|1987 ||4,899 ||9,863 ||546 ||15,308 |
|1988 ||6,822 ||8,266 ||493 ||15,581 |
|1989 ||2,255 ||8,174 ||185 ||10,614 |
|1990 ||10,598 ||23,258 ||416 ||34,272 |
|1991 ||9,708 ||9,573 ||353 ||19,634 |
|1992 ||15,217 ||22,468 ||200 ||37,885 |
|1993 ||20,914 ||19,173 ||306 ||40,393 |
|1994 ||16,934 ||17,554 ||143 ||34,631 |
|1995 ||10,892 ||18,950 ||273 ||30,115 |
|1996 ||15,238 ||18,937 ||198 ||34,373 |
|1997 ||12,020 ||9,939 ||378 ||22,337 |
|1998 ||22,987 ||8,455 ||176 ||31,617 |
|1999 ||13,649 ||13,145 ||465 ||27,259 |
|2000 ||17,765 ||19,230 ||n/a ||36,994 |
|2001 ||17,097 ||23,052 ||n/a ||40,149 |
|2002 ||10,988 ||6,519 ||n/a ||17,507 |
|2003 ||7,593 ||3,002 ||n/a ||10,595 |
|2004 ||8,781 ||7,580 ||n/a ||16,361 |
|2005 ||952 ||176 ||n/a ||1,128 |
|2006 ||913 ||840 ||n/a ||1,753 |
|2007 ||140 ** ||1.2 ** ||n/a ||141 |
|2008 ||0 ||0 ||n/a ||0 |
|AVERAGE (1990-2004) ||6,394 ||26,337 ||318 ||32,824 |
|** Experimental Fishery |
| ||Type ||Value ||Technical basis |
|Precautionary approach ||Blim ||21 000 t ||Blim: Bloss = 21 000 t (1989 SSB). |
| ||Bpa ||33 000 t ||Bpa = Bloss × exp(1.645σ). |
| ||Flim ||- ||Not defined. |
| ||Fpa ||1.0–1.2 ||Fpa: = F for 50% spawning potential ratio, i.e. the F at which the SSB/R is half of what it would have been in the absence of fishing. |
|Targets ||Fy ||- ||Not defined. |
|(unchanged since 2003) |
Because the assessment provides the probability distributions for the SSB, it is possible to estimate directly the risk of the SSB falling below Blim
reference points may become unnecessary.
Basis: R(2010) from distribution of recruitment at age 1 in biomass (2002–2009) = 17400 t. (median). Total catch: 50% allocated to second half of 2009 and 50% to first half of 2010.Outlook for 2010
(1st July 2009–30 June 2010)
|Median SSB 2010 |
|0 ||0.37 ||25550 |
|1000 ||0.40 ||24962 |
|3000 ||0.44 ||23785 |
|5000 ||0.47 ||22609 |
|7000 ||0.49 ||21432 |
|9000 ||0.52 ||20256 |
Weights in tonnes
Shaded scenarios are not considered consistent with the precautionary approach
Scientific AdviceSingle-stock exploitation boundariesThere is a 37% risk that SSB in 2010 will be below Blim even with no catch. ICES advises on the basis of exploitation boundaries in relation to precautionary limits that the fishery should remain closed until the stock condition has improved. The stock condition can be re-evaluated when estimates of the 2010 SSB and 2009 year class are available based on the spring 2010 acoustic and DEPM surveys. This implies a closure of the fishery until at least July 2010. Table 18.104.22.168
Anchovy in Subarea VIII (Bay of Biscay). Single stock exploitation boundaries (advice), management and landings
|Year || |
|Predicted catch corresp. to advice ||Agreed TAC ||Official landings ||ICES landings |
|1987 ||Not assessed ||- ||32 ||14 ||15 |
|1988 ||Not assessed ||- ||32 ||14 ||16 |
|1989 ||Increase SSB; TAC ||10.01 ||32 ||n/a ||11 |
|1990 ||Precautionary TAC ||12.3 ||30 ||n/a ||34 |
|1991 ||Precautionary TAC ||14.0 ||30 ||n/a ||20 |
|1992 ||No advice ||- ||30 ||n/a ||38 |
|1993 ||Reduced F on juveniles; closed area ||- ||30 ||n/a ||40 |
|1994 ||Reduced F on juveniles; closed area ||- ||30 ||n/a ||35 |
|1995 ||Reduced F on juveniles; closed area ||- ||33 ||n/a ||30 |
|1996 ||Reduced F on juveniles; closed area ||- ||33 ||n/a ||34 |
|1997 ||Reduced F on juveniles; closed area ||- ||33 ||n/a ||22 |
|1998 ||Reduced F on juveniles; closed area || ||33 ||n/a ||32 |
|1999 ||Reduced F on juveniles, closed area || ||33 ||n/a ||27 |
|2000 ||Closure of the fishery ||0 ||33 ||n/a ||37 |
|2001 ||Preliminary TAC corresponding to recent exploitation ||18 ||33 ||n/a ||40 |
|2002 ||Preliminary TAC corresponding to recent exploitation ||33 ||33 ||n/a ||17.5 |
|2003 ||Preliminary TAC corresponding to recent exploitation ||12.5 ||33 ||n/a ||10.6 |
|2004 ||Preliminary TAC corresponding to recent exploitation ||11 ||33 ||n/a ||16.4 |
|2005 ||Rebuilding SSB ||5 ||30 ||n/a ||1.1 |
|2006 ||Closure of the fishery* ||0 ||5 || ||1.8 |
|2007 ||Closure of the fishery* ||0 ||0 ||- || 0.12 |
|2008 ||Closure of the fishery * ||0 ||0 ||- ||0 |
|2009 ||Closure of the fishery * ||0 ||0 ||- ||03 |
|2010 ||Closure of the fishery * ||0 || || || |
Weights in ‘000 t.
1Mean catch of 1985–1987.
3Preliminary estimate of catches up to 1st of July.
n/a: not available.
* to be reconsidered after new information from Spring survey.
Management unit: Yes
There are no explicit management objectives for this stock. The present closure of the fishery aims at protecting the remaining stock until a strong year class recruits to the stock.
Management AdviceManagement considerations
Anchovy is a short-lived species, with the fishable stock consisting primarily of one-year-old fish. The estimate of recruitment at age 1 is a key factor in determining a TAC.Stock biomass has been low because recruitment has been low since 2002. The fishery has been stopped from 2005 onwards. There are no indications how long the low recruitment period will last and whether continued low SSB will reduce future recruitments. ICES advice is made in the frame of the precautionary approach, therefore, in the present situation, the catch forecast is made under the assumption that the recent low recruitment will continue. The recruitment in 2010 in the forecast is assumed to be similar to recent low recruitments (2002–2009). The forecast indicates that the probability of SSB in 2010 being below Blim is 37% without any catches. The forecast is relatively insensitive to the allocation of catches to different seasons
The closure of the fishery for the last four years has led to an increase in the abundance of older anchovy. If recruitment persist to be low, the contribution of older fish to spawning becomes crucial.In the past, a TAC was set independent of the state of the stock in the range of 30 000 t to 33 000 t, and this had limited impact in regulating catches in the fishery.
Recent developments in management have been moving towards an in-year monitoring regime, as recommended previously by ICES. The assessment of anchovy is based on the survey results in the spring and the catch data. Hence, the most up-to-date assessment can be obtained in June as done in this assessment. TACs may be set for the whole period July–June, as the only input data for the time being are available in spring.Harvest control rules (HCR) for anchovy are currently under development outside ICES, to be implemented when the stock has recovered. The results of an ICES benchmark assessment planned for anchovy in September 2009 may be useful in the evaluation of proposed management measures. ICES notes that the criterion for accepting HCR as precautionary would include rules that imply a low risk of reducing the SSB to a level which may imply further reduction in recruitment. Supplementary measures (area closures, minimum landing size) may be considered in addition to TACs.
Surveys to estimate juvenile abundance in autumn have now been conducted for six years. ICES considers these surveys as a promising approach to providing the information necessary to revise the TAC at the beginning of the year. However, the series so far covers only a period where the recruitment has been low. It is not known how a medium or strong year class will show in the survey. Therefore, until at least one medium or strong year class has been both measured in the survey and confirmed in the subsequent assessment, ICES will not be in the position to advice on a revised TAC for the first half year on the basis of the survey.
Biological State and Trend
Based on the most recent estimates of SSB, ICES classifies the stock as being at risk of reduced reproductive capacity. Although median SSB in 2009 is estimated to be above Blim, this estimate has a 47% probability of being below Blim. Low recruitment at age 1 since 2002 and almost complete recruitment failure of the 2004 year class are the primary causes of the low stock size. The recruitment at age 1 in 2009 is at the same level as last year but lower than in 2006 and 2007.
|Spawning biomass in relation to precautionary limits ||Fishing mortality in relation to precautionary limits ||Fishing mortality in relation to highest yield ||Comment |
|Increased risk ||Not harvested ||Undefined ||Fishery closed since July 2005 |
Source of information
ICES.2009.Report of the ICES Advisory Committee, 2009. ICES Advice, 2009.