Spanish fisheries in NAFO Subarea 3

The aim of this paper is to characterize the different Spanish fisheries in NAFO Subarea 3 during the period 2005- 2011 base on the catch composition, depth and gear used by the Spanish fleet. Normally a fishery is determined by its catch composition, the area where it was took and the fleet and gear used to catch it. Based on the results, it can conclude that Spanish fleet had six different fisheries in the period 2005-2011 in NAFO Division 3LMNO depending on the target species, area, depth and gear (mesh size). The Spanish fisheries were the following: 1) In Divisions 3LMNO at more than 600 meters depth with demersal 130 mm mesh size gear with Greenland halibut (86%) as target species and the roughhead grenadier (4%) and the redfish (2%) as main by-catch species. 2) In Divisions 3LMNO, mainly in Div 3O and 3M with demersal 130 mm mesh size gear in the 200-600 strata. The target species was the redfish (80%) and the main by-catch species were Greenland halibut (4%), American plaice (4%), cod (3%) and witch flounder (3%). 3) In Divisions 3NO with demersal 130 mm mesh size at depth less than 200 meters. This is a mix fishery with different catch composition in Div. 3N (56% American plaice, 26% yellowtail flounder, 10% cod and 6% skates) than in Div. 3O (57% redfish, 14% American plaice, 12% skates and 7% witch flounder). 4) In Divisions 3NO with 280 mm mesh size at less than 200 meters depth. The target species was the skates (63%) with American plaice (19%), yellowtail flounder (10%) and cod (6%) as main by-catch species. 5) In Division 3LM with 40 mm mesh size at depth between 300-500 meters. The target species of this fishery was the shrimp with 98% of the catches and only a 2% of redfish as by-catch. 6) In Division 3M at depth between 150-550 meters targeting cod with 130 mm mesh size gear. The target species of this fishery was cod (92%) and the most important species in the by catch was redfish (7%)

A method to estimate the NAFO Subarea 2+3KLMNO GHL catches based on survey information

In the period 2011-2015 the SC has not approved the NAFO Subarea 2+3KLMNO GHL catches due to inconsistencies in the available information to estimate it. The method propose in this paper is based on the linear regression relationship between the Scientific Observers and Surveys CPUEs. The method has some caveats. Nevertheless, the method could be used to know the level of discrepancies between the STATLANT and the estimation made based on the Scientific Observers CPUEs in some cases. Results show that the discrepancies between the estimations made base on the scientific observers CPUEs and the STATLANT figures present a decreased trend in time, being around the 50% more in the last two years. This seems to be an important improvement in the quality of the STATLANT figures in the last years compare with the years before. It is proposed to use the method explain in this paper to estimate catches in the 2011-2014 period where the discrepancies where bigger and used the official NAFO information (STATLANT, DCR, haul by haul data) for 2015 where the discrepancies seems to be smaller.Postprint0,000

Assessment of Splendid alfonsino (Beryx splendens) in NAFO Subarea 6

Commercial aggregations of alfonsino (Beryx splendens) on the Corner Rising and in the area of North Azores were discovered for the first time on board the USSR exploratory vessels the mid-70s of last century. The NAFO SC recommended that precautionary regulations of the mid-water trawl fishery on splendid alfonsino be put in place. In 2014 NAFO Fisheries Commission request for scientific advice on provide a stock assessment for alfonsino. Taking in account the alfonsino spatial distribution associated with seamounts, their life history and their aggregation behavior and due to the limited availability of data it could be advised a scalar approaches to advice the future catch levels by using simple scalar multipliers applied to current or historical catch patterns. Based on this approach a maximum catch limit of 200 tonnes (the mean of the last 6 years) on 16-18 days or around 120 fishing hours could be advised by year in Kükenthal seamount and recommend that the exploitation of new seamounts should not be allowed to prevent the exploitation of populations that have not yet been fished

An assessment of NAFO roughhead grenadier Subarea 2 and 3 stock

The aim of this paper is to present the status of NAFO roughhead grenadier Subarea 2 and 3 stock based on different assessments models using all the available information. Different assessment methods have been applied based on the data available: Extended Survivors Analysis, a Stock-Production Model Incorporating Covariates (ASPIC) and a qualitative assessment based on survey and fishery information. XSA results are considered uncertainties due to the low Fishing mortality estimated compare with the natural mortality level assumed and the high number of iterations needed to reach the convergence. ASPIC results make sense with historical data available for this stock despite the uncertainty in the B1/K parameter and the low contrast index value. Although all these problem both models results present a very similar trend in the fishing mortality and biomass values and are comparable to the qualitative assessment base on the surveys information. Biomass presents in all methods a general increased trend in the 1995-2006 period and between 2006 and 2009 is more or less stable at high levels. Between 2009-2012 presents a decreasing trend in the surveys indices and XSA results however remains stable at high levels in the ASPIC results. Trends of the different estimations of F were very similar. F presents a decreasing trend since 1998 till 2006 and since then is more or less stable at very low levels. All recruitment indices analysed show a clear recruitment pick around 2004 and the XSA and survey length abundance show other quite good recruitment in 2012 despite the difficult to follow cohorts strength

Roughhead Grenadier subarea 2 and 3 XSA model configuration

STACFIS recommended in 2007 to explore the eXtended Survivors Analysis (XSA) configuration of the analytical assessment presented (definition of the plus group, catchability model and the shrinkage options), as well as the incorporation of the new survey information into the model. This document tries to respond this recommendation with the following suggestions. To establish the plus group in 17+ because the percentage of maturity (93%) as well as the percentage in biomass (10%) and abundance (2%) would be reasonably and the stability of the model would improve appreciably compare with the 19+ plus group used in the 2007 XSA. To define the Fbar age range between 6 and 13 years because this range is representative of the most important ages in the catches and avoid most of the problems of the partial recruitment and the plus group assumptions. To consider all ages with catchability independent of the year class strength and to use a mean model to determine the relationship between the log CPUE and the Log VPA abundance and setup q constant for ages older than 15 years. To use the last two ages (14-15) and the last two years (2005-2006) as range for the shrinkage with a standard error of 1.0 for the F shrinkage means

Method to estimate catches based on the Observers on board information

The aim of this document is to present the method used in the period 2004-2010 to estimate the Spanish catch by species based in the information collecting by the “NAFO Observers” and the “Spanish Scientific Observers”

An assessment of NAFO roughhead grenadier Subarea 2 and 3 stock.

The aim of this paper is to present the status of NAFO roughhead grenadier Subarea 2 and 3 stock. Different assessment methods have been applied based on the available data: XSA, ASPIC and a qualitative assessment based on survey and fishery information. The fit of the data to the XSA and ASPIC has been very poor mainly due to lack of contrast and conflicting information from the surveys data. Therefore the results are not considered representative of the stock situation. There are not available surveys indices covering the total distribution, in depth and area, of this stock. Biomass indices from the surveys with depth coverage till 1400 meters are considered as the best survey information available to monitor trends in resource status because they cover the depth distribution of roughhead grenadier fairly well. Surveys biomass indices present a general increasing trend in the period 1995-2004. In the period 2005-2012 all available indices show a clear downward trend except the Canadian Fall (2J+3K) index. In the most recent period (2013-2015) the information of the different indices is contradictory, the Canadian 2J3K and the EU 3L show an increase while EU-FC and EU 3NO continue to decline. With regard to fishing mortality, the trends of the different estimations of F were very similar. F presents a decreasing trend since 1998 till 2006 and since then is more or less stable at very low levels. The recruitment indices analysed (Surveys length and age distributions) show at least three good cohorts: 1993, 2001 and 2012 year classes. To confirm the strength of the last good year class (2012) it would need to have more information about it.Postprint0,000

An assessment of NAFO roughhead grenadier Subarea 2 and 3 stock.

The aim of this paper is to present the status of NAFO roughhead grenadier Subarea 2 and 3 stock based on different assessments models using all the available information. Different assessment methods have been applied based on the data available described above. The assessment was carried out with three different methods: Extended Survivors Analysis (XSA, Shepherd, 1999; Darby and Flatman, 1994), a Stock-Production Model Incorporating Covariates (ASPIC, Prager 1994 and 2004) and a qualitative assessment based on survey and fishery information. XSA and ASPIC results are considered uncertainties due to the low Fishing mortality estimated compare with the natural mortality level assumed in the case of the XSA and due to the lack of contrast in the data used in the ASPIC case. Although all these problem both models results present a very similar trend in the fishing mortality and biomass values and are comparable to the qualitative assessment base on the Canadian fall survey series (Div. 2J+3K) and the Spanish survey in Divisions 3NO that there are considered by the NAFO Scientific Council as the best survey information to monitor trends in resource status. Biomass presents in all methods a general increased trend in the analysed period with its maximum level in the last years. With regard to fishing mortality estimates from different methods, it can be observed that the trends of the different estimations of F were very similar and that the actual level of F is the minimum of the period due to the increase of the biomass and the decrease of the caches in the last years. The strong 2001 year class have been weaker than expected since 2005 in both survey indices. The level of the recruitment in last period appears to be smaller than the observer before

Quality of the Surveys Information in Relation with the Greenland Halibut Assessment of Subarea 2 and Divisions 3KLMNO

The aim of this paper is to provide a study of the quality of the surveys information in relation with the Greenland halibut assessment of the NAFO Subarea 2 and Divisions 3KLMNO. The surveys abundance correlation within surveys, between surveys and XSA showed that the surveys had many difficulties to track ages older than 6 years. For Flemish Cap survey and Canadian Spring Survey, the problem to track these ages could be principally the depth coverage of the surveys, but for the other surveys this lack of tracking could be due to different reasons as age reading inconsistencies and changes in catchability of these ages in the surveys

Report of the NAFO Precautionary Approach Working Group (PA-WG)

The meeting was opened by the co-Chairs Fernando González-Costas and Steven Cadrin at 09:00 hours (Atlantic Daylight Time in Halifax, Nova Scotia) on Thursday, 19 May 2022