ICES Advice on fishing opportunities, catch, and effort Northeast Atlantic Ecoregion Published 9 October 2015

9.3.28 Portuguese dogfish (Centroscymnus coelolepis) in the Northeast Atlantic

ICES stock advice

ICES advises that when the precautionary approach is applied for Portuguese dogfish in the Northeast Atlantic, fishing mortality should be minimized and no targeted fisheries should be permitted. This advice is valid for 2016 to 2019.

Stock development over time

Consistent landings data for Portuguese dogfish are not available for the entire stock area. Landings of deep-water sharks (primarily leafscale gulper shark and Portuguese dogfish) peaked in 2001–2004 and have declined thereafter in response to reduced abundance and restrictive management measures.

Figure 9.3.28.1 Portuguese dogfish in the Northeast Atlantic. Combined landings (t) of deep-water sharks (primarily relating to leafscale gulper shark and Portuguese dogfish; 2010–2014 data refer solely to Portuguese dogfish).

Stock and exploitation status

Table 9.3.28.1 Portuguese dogfish in the Northeast Atlantic. State of the stock and fishery relative to reference points. Fishing pressure Stock size 2012 2013 2014 2013 2014 2015 Maximum MSY FMSY Undefined Undefined sustainable yield Btrigger Precautionary Fpa, Undefined Bpa, Blim Undefined approach Flim Management F - - - Not applicable SSB - - - Not applicable plan MGT MGT Qualitative - Unknown - Unknown evaluation

Catch options

The ICES framework for category 6 was applied (ICES, 2012) as the existing survey (Scottish slope, 2000–2013) is not considered representative of the entire stock. For stocks without information on abundance or exploitation, ICES considers that a precautionary reduction of catches should be implemented unless there is ancillary information clearly indicating that the current level of exploitation is appropriate for the stock.

ICES Advice 2015, Book 9 1 Published 9 October 2015 Advice on fishing opportunities, catch, and effort

In its most recent advice for 2013–2015 ICES advises that there should be no catches for this stock. Landings in the last five years have been close to zero. Therefore, ICES advises that when the precautionary approach is applied, fishing mortality should be minimized and no targeted fisheries should be permitted. Table 9.3.28.2 Portuguese dogfish in the Northeast Atlantic. For stocks in ICES data categories 3—6, one catch option is possible. Recent advised catch (2014) No catch Discard rate Unknown Precautionary buffer Not applied - Catch advice Fishing mortality minimized and no targeted fisheries

Basis of the advice

Table 9.3.28.3 Portuguese dogfish in the Northeast Atlantic. The basis of the advice. Advice basis Precautionary approach Management plan There is no management plan for this stock.

Quality of the assessment

Many countries used to report landings of Portuguese dogfish combined with other deep-water sharks, mainly leafscale gulper shark in categories such as “siki sharks”. Unless suitable data can be found to enable splitting of the catch data, historical catch levels will remain uncertain. In the past, misreporting was considered a minor problem, but this is likely to have changed since restrictive catch levels were adopted for deep-water sharks. Fishery-independent data are derived from the Scottish deep-water survey that takes place in only a small proportion of the stock range. These data are only available for after the development of the fishery. There are no fishery-independent data for areas further south which prevents understanding abundance in these areas.

Figure 9.3.28.2 Scottish deep-water trawl survey (n h−1) for Portuguese dogfish (2000–2013; no surveys in 2001, 2003, and 2010).

Issues relevant for the advice

A TAC for deep-water sharks was first introduced in 2005. The TAC was reduced to zero in 2010 and has remained at zero since then. Discarding is known to occur but has not been fully quantified and preliminary estimates are uncertain. Discard survival is expected to be very low.

2 ICES Advice 2015, Book 9 ICES Advice on fishing opportunities, catch, and effort Published 9 October 2015

ICES advises that fishing mortality should be minimized; therefore, any possible provision for bycatch to be landed should be part of a management plan which includes close monitoring of the stock. Earlier studies indicated that the relative abundance of Portuguese dogfish combined with leafscale gulper shark declined in the 1990s in ICES Subareas V, VI, and VII.

Reference points

No reference points have been defined for this stock.

Basis of the assessment

Table 9.3.28.4 Portuguese dogfish in the Northeast Atlantic. The basis of the assessment. ICES stock data category 6.3.0 (ICES, 2015a) Assessment type No assessment (ICES, 2015b). Input data Landings. Discards and bycatch Unknown. Indicators Scottish deep-water survey. Other information Life history, historical data (including from the benchmark in 2010). Working group Working Group on Elasmobranch Fisheries (WGEF).

ICES Advice 2015, Book 9 3 Published 9 October 2015 Advice on fishing opportunities, catch, and effort

Information from stakeholders

No information has been provided.

History of advice, catch, and management

Table 9.3.28.5 Portuguese dogfish in the Northeast Atlantic. History of ICES advice, the agreed TAC, and ICES estimates of landings in EU and non-EU waters. Weights in tonnes. Predicted catch Agreed EU TAC ICES Year ICES advice* corresp. to advice* for deep-water sharks landings** 2001 No advice - - 10105 2002 Reduce exploitation - - 8093 2003 No advice - - 10876 2004 No advice - - 9031 2005 Zero catch 0 7020 5053 2006 No new advice, same as for 2005 0 7020 2727*** 2007 TAC = 0, prevent bycatch 0 2591 2023 2008 No new advice, same as for 2007 0 1715 1393 2009 Zero catch 0 859 220 2010 No new advice, same as for 2009 0 0 32 2011 Zero catch 0 0 1 2012 No new advice, same as for 2011 0 0 0 2013 Zero catch 0 0 0 2014 No new advice, same as for 2013 0 0 5 2015 No new advice, same as for 2014 0 Precautionary approach, fishing mortality 2016 0 minimized and no targeted fisheries 2017 Quadrennial advice 0 2018 Quadrennial advice 0 2019 Quadrennial advice 0 * Advice prior to 2013 was for Portuguese dogfish and leafscale gulper shark combined. ** Combined landings for Portuguese dogfish and leafscale gulper shark (may also include other deep-water shark species) before 2010. *** Landings greatly reduced due to the ban of the gillnet fishery targeting deep-water sharks in ICES Subareas VI, VII, and XII. This ban was extended to all ICES Subareas in 2009.

History of catch and landings

This species is a bycatch in the deep-water trawl and longline fisheries. Table 9.3.28.6 Portuguese dogfish in the Northeast Atlantic. Catch distribution by fleet of Portuguese dogfish in 2014 as estimated by ICES. Total catch (2014) Landings Discards 5 tonnes Unknown Unknown Proportion by fleet is unquantified

4 ICES Advice 2015, Book 9 ICES Advice on fishing opportunities, catch, and effort Published 9 October 2015

Table 9.3.28.7 Portuguese dogfish in the Northeast Atlantic. History of commercial landings (ICES estimates) of deep-water dogfish (primarily leafscale gulper shark and Portuguese dogfish) in EU and non-EU waters, presented by country participating in the fishery (in tonnes). UK UK Spain Spain Faroe Year France Ireland Iceland Portugal Germany Estonia Latvia Lithuania Poland Russia Norway Total (Scot) (E&W) (Basque) (Galicia) Islands

1988* 0 0 0 0 0 0 560 0 0 0 0 0 0 0 0 0 560 1989* 0 20 0 0 0 0 507 0 0 0 0 0 0 0 0 0 527 1990* 140 14 0 0 0 0 481 0 0 0 0 0 0 0 0 0 635 1991* 1288 24 104 0 0 0 1093 0 0 0 0 0 0 0 0 0 2509 1992* 3104 165 80 0 1 0 1128 148 0 0 0 0 0 0 0 0 4626 1993* 3468 469 174 0 1 0 946 91 0 0 0 0 0 0 3 0 5152 1994* 3812 743 387 0 0 0 1155 358 0 0 0 0 0 0 0 0 6455 1995* 3186 801 986 33 0 0 1354 92 0 0 0 0 0 0 60 0 6512 1996* 3630 576 1036 5 0 286 1189 164 0 0 0 0 0 0 282 0 7168 1997* 3095 766 2202 0 0 473 1314 106 0 0 0 0 0 0 226 0 8182 1998* 3177 1007 1494 3 5 561 1260 40 0 0 0 0 0 0 158 0 7705 1999* 3079 625 1019 2 0 450 1036 214 0 0 0 0 0 0 54 5 6484 2000* 3519 623 413 138 0 280 1108 265 0 0 0 0 0 572 23 118 7059 2001* 3684 2429 320 454 0 608 1151 431 0 0 14 0 0 615 0 399 10105 2002* 2103 1184 335 577 0 621 1198 518 53 0 40 8 0 1381 0 75 8093 2003* 1454 1594 4027 493 0 719 1180 640 4 0 28 0 0 737 0 0 10876 2004* 1189 1135 3610 764 0 563 1125 0 0 0 0 0 0 626 0 19 9031 2005* 866 802 1533 381 0 359 1033 79 0 0 0 0 0 0 0 0 5053 2006* 744 184 537 113 0 78 1072 0 0 0 0 0 0 0 0 0 2727 2007* 855 86 23 36 0 0 522 0 0 0 1 0 500 0 0 0 2023 2008* 802 49 7 8 0 0 463 0 0 0 62 0 0 0 3 0 1393 2009* 52 30 0 0 0 84 54 0 0 0 0 0 0 0 0 0 220 2010 10 20 0 0 0 0 2 0 0 0 0 0 0 0 0 0 32 2011 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 2012 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2013 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2014 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 *Combined landings of leafscale gulper shark and Portuguese dogfish.

ICES Advice 2015, Book 9 5 Published 9 October 2015 Advice on fishing opportunities, catch, and effort

Table 9.3.28.8 Portuguese dogfish in the Northeast Atlantic. History of commercial landings (ICES estimates) of deep-water dogfish (primarily leafscale gulper shark and Portuguese dogfish) in EU and non-EU waters, presented by area (in tonnes). Landings are combined until 2009; from 2010 onwards landings are presented by species (leafscale gulper shark, Portuguese dogfish). Unknown Year IVa Va Vb VI VII VIII IX X XII XIV Total area 1988 0 0 0 0 0 0 560 0 0 0 0 560 1989 12 0 0 8 0 0 507 0 0 0 0 527 1990 8 0 140 6 0 6 475 0 0 0 0 635 1991 10 0 75 1013 265 70 1075 0 1 0 0 2509 1992 140 1 123 2013 1171 62 1114 0 2 0 0 4626 1993 63 1 97 2781 1232 25 946 0 7 0 0 5152 1994 98 0 198 2872 2087 36 1155 0 9 0 0 6455 1995 78 0 272 2824 1800 45 1354 0 139 0 0 6512 1996 298 0 391 3639 1168 336 1189 0 147 0 0 7168 1997 227 0 328 4135 1637 503 1311 0 32 9 0 8182 1998 81 5 552 4133 1038 605 1220 0 56 15 0 7705 1999 55 0 469 3471 895 531 972 0 91 0 0 6484 2000 1 1 410 3455 892 361 1049 0 890 0 0 7059 2001 3 0 475 4459 2685 634 1130 0 719 0 0 10105 2002 10 0 215 3086 1487 669 1198 0 1416 12 0 8093 2003 16 0 300 3855 3926 746 1180 0 849 4 0 10876 2004 5 0 229 2754 3477 674 1125 0 767 0 0 9031 2005 4 0 239 1102 842 376 1033 1 134 0 1323 5054 2006 4 0 195 638 323 208 1325 0 0 0 34 2727 2007 3 0 590 737 94 23 517 0 1 61 0 2025 2008 1 0 171 621 111 27 463 0 0 0 0 1393 2009 1 0 24 54 4 105 33 0 0 0 0 220 2010 1 – 0 0 – 0 38 – 8 21 – 22 4 – 0 4 – 1 4 – 1 0 – 0 0 – 0 0 – 0 0 – 0 71 – 33 2011 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 1 – 0 1 – 1 0 – 0 0 – 0 0 – 0 0 – 0 2 – 1 2012 0 – 0 0 – 0 51 – 0 0 – 0 0 – 0 0 – 0 1 – 0 0 – 0 0 – 0 0 – 0 0 – 0 52 – 1 2013 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 2014 0 – 0 0 – 0 32 – 5 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 0 – 0 33 – 5

Summary of the assessment

There is no assessment for this stock.

Sources and references

ICES. 2012. ICES Implementation of Advice for Data-limited Stocks in 2012 in its 2012 Advice. ICES CM 2012/ACOM:68. 42 pp. ICES. 2015a. Advice basis. In Report of the ICES Advisory Committee, 2015. ICES Advice 2015, Book 1, Section 1.2. ICES. 2015b. Report of the Working Group on Elasmobranch Fishes (WGEF), 17–23 June 2015, Lisbon, Portugal. ICES CM 2015/ACOM:19.

6 ICES Advice 2015, Book 9