Bellido-Millán, J.M. (José María)

Carbonell, A. (Ana)

García-Jiménez, M.T. (María Teresa)

Goñi, R. (Raquel)

Mallol, S. (Sandra)

Mendoza, M.

Pérez-Contreras, M.N. (María Nélida)

Valeiras, J. (Julio)

English

Repositorio Institucional Digital del IEO

  2003 2004 2005 2006 2007 20002040608010 2003 2004 2005 2006 2007 20002040608010Discard Rate (%) Weight                                                          Individuals Discards rate in a selected species (Merluccius merluccius)     3. Discard rate          Percentage of individuals discarded in the full catch of the métier. 2003 2004 2005 2006 2007 20020406080100   %    1. Métier Catch Mean Size     2. Metier Discard Mean Size          The mean size of each species is standardized according to the mean size of that species for the first year available in the database. The grand mean is obtained from the mean of the Standardized mean size values of the five representative species 2003 2004 2005 2006 2007 20080.60.81.01.2       Cm 2003 2005 2007152025303540452004 2006 2008152025303540452003 2005 200715202530354045Cm Trachurus trachurus, Pair-trawl (PTB_NorthIberian) Sorting Size: Min., Q5, Q25, Median, Q75, Max, Mean and Std. Dev.  Catch                                                              Discarded                                                           Landed Threatened Species: Relative abundance of individuals in the Catch and their Discard  Rate. 2003 2004 2005 2006 2007 20080.00.51.01.5 Per 10000 individ2003 2004 2005 2006 2007 200020406080100  Discard (%)Pair-trawl (PTB_NorthIberian) Synthesis Indicators (Pair trawl PTB_NorthIberian) THE NEED…. There is a need for simple and straightforward tools for a proper fisheries management. These tools are especially needed to monitor and manage discard issues. In the EU there is intensive data collection of bycatch and discard onboard commercial vessels but until now there have been few attempts to describe the general patterns in these data, and still less to understand the factors that determine what and how much is discarded.  We propose  here a set of indicators to monitor discard issues for selected Spanish fisheries. These indicators allow to describe the composition of catches and discards.   Indicators  for the whole catch Simpson´s Diversity Index SDI  2003 2005 20070.00.20.40.60.81.0 Catc2003 2005 20070.00.20.40.60.81.0 a ded2003 2005 20070.00.20.40.60.81.0 sca ded2003 2005 20071.01.52.02.53.0 a ded / Ratio. . . Pair-trawl (PTB_NorthIberian) 0 Catch 0 Landed 0 Discarded .0   Landed /Discarded Merluccius merluccius , Pair-trawl (PTB_NorthIberian) Minimum Marketable Size (Minimum length class landed by fishing trip in the entire set of trips of the Area for which it is calculated)  24.024.525.025.526Cm4.04.55.05.5   2003 2004 2005 2006 2007 2008 2003 2004 2005 2006 2007 2008Mean                                                    Standard Deviation   Indicators for the selected representative species (figures for metier Pair trawl North Iberian as example; We made the same for the other three metiers) Pair-trawl (PTB_NorthIberian) Weight                                                           Individuals   Discards rate in the whole catch   02040608010Discard Rate (%   02040608010   2003 2004 2005 2006 2007 200   2003 2004 2005 2006 2007 200 4. Relative Minimum Marketable Size         Minimum mesh size/minimum landing size (MMS/MLS) 2003 2004 2005 2006 2007 2001.21.41.61.8   Ratio (MMS/MLS5. Relative Landing Diversity            Simpson´s Index of Diversity (SID) of the landed individuals divided by the SID of the discarded individuals. 2003 2004 2005 2006 2007 2001.01.52.02.53.03.  Ratio (Landed / D6. Threatened Species Relative abundance           The number of individual of Threatened Species multiplied for one million and divided by the number of individual of the full catch. 2003 2004 2005 2006 2007 200050100150   No. of individual  THE PRESSURE INDICATORS… Pressure indicators were developed within the BADMINTON project (EraNEt – MariFish) The goal of the Badminton project is precisely the development of a number of indicators that describe the composition of catches and discards at both the stock and community levels. Here we propose a set of general indicators for some Spanish selected fisheries: total discards and discards rate in the total catch and some representative species, sorting size for the total catch, retained and discarded, and also for some individual representative species, minimum marketable size, the relative abundance of threatened species in the catch and their discard rate and the Simpson´s Diversity Index of the catch, landing and discards. The indicators are estimated by fleet for a range of previously selected representative species both commercial and non-commercial. These include (1) the European hake (Merluccius merluccius ), (2) the spotted dogfish (Scyliorhinus canicula), (3) the most landed and (4) the most discarded species, and (5) a species representative of the metier. Other indicators are estimated for the whole catch and discard.   THE SYNTHESIS INDICATORS… One of the main problems when dealing with discard data is the huge amount of information needed to have a proper and complete view. Additionally this information is often difficult to interpret in its whole. We introduce 6 new synthesis indicators: Metier Catch Mean Size, Metier Discard Mean Size, Metier Discard Rate, Relative Minimum Marketable Size, Relative Landing Diversity and Threatened Species Relative abundance.   In figures we show the recent trend of these synthesis indicators for four selected Spanish fleets: Pair-trawl (PTB_NorthIberian) and Otter trawl (OTB_CelticSea) in Atlantic waters and Otter-Trawl (OTB_Alboran Sea) and Trammel Net (GTR_Balearic) in Mediterranean fishing grounds.   1. Métier Catch Mean Size  Synthesis Indicators (Otter trawl OTB Celtic Sea)  2. Métier Discard Mean Size   3. Discard rate   4. Relative Minimum Marketable  Size   5. Relative Landing Diversity  6. Threatened Species Relative abundance  1. Métier Catch Mean Size  Synthesis Indicators (Otter trawl OTB Alboran Sea)  2. Métier Discard Mean Size   3. Discard rate   4. Relative Minimum Marketable  Size   5. Relative Landing Diversity  6. Threatened Species Relative abundance  1. Métier Catch Mean Size  Synthesis Indicators (Trammel Net GTR Balearic)  2. Métier Discard Mean Size   3. Discard rate   4. Relative Minimum Marketable  Size   5. Relative Landing Diversity  6. Threatened Species Relative abundance 2003 2004 2005 2006 2007 20080.60.70.80.91.01.11.22003 2004 2005 2006 2007 20080.80.91.01.11.22003 2004 2005 2006 2007 20080.80.91.01.11.2   2003 2004 2005 2006 2007 2008020406080100  %2003 2004 2005 2006 2007 20080.91.01.11.21.31.41.5   Ratio (MMS/MLS)2004 2005 2006 2007 20080.60.81.01.2  Ratio (Landed SI/Dis 2003 2004 2005 2006 2007 200805101520  Number of individua 2003 2004 2005 2006 2007 20080.91.01.11.21.32003 2004 2005 2006 2007 20080.91.01.11.21.3   2003 2004 2005 2006 2007 2008020406080100  %2003 2004 2005 2006 2007 20081.11.21.31.41.51.61.7    Ratio (MMS/MLS)2004 2005 2006 2007 20080.81.01.21.41.6  Ratio (Landed SI/D 2003 2004 2005 2006 2007 20080.00.51.01.52.0  Number of individua 2002 2004 2006 20080.80.91.01.11.21.32002 2004 2006 20080.80.91.01.11.21.3   2002 2004 2006 2008020406080100  %2002 2004 2006 20081.01.21.41.61.82.0   Ratio (MMS/MLS)2004 2005 2006 2007 20080.70.80.91.0  Ratio (Landed SI/D 2002 2004 2006 200805101520  Number of individua BADMINTON-Spain is funded by Spanish Goverment, Ministry of Science and Innovation (Convocatoria PN I+D+i, EUROINVESTIGACIÓN 2009. Nº REF: EUI2009-04022).  Pressure indicators describing by-catch and discards in selected Spanish fisheries JM. Bellido, M. Mendoza, J. Valeiras, T. Garcia, N. Pérez, S. Mallol, R. Goñi, and A. Carbonell Instituto Español de Oceanografía. Presented by Aina Carbonell. Contact at josem.bellido@mu.ieo.es  Research Group - Grupo de Investigación 

Pressure Indicators describing Bycatch and Discards in selected Spanish fisheries

http://www.repositorio.ieo.es/e-ieo/bitstream/10508/5102/1/CM%202012-C25.pdf

Pressure Indicators describing Bycatch and Discards in selected Spanish fisheries

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