Catch, effort and biological data relating to four demersal species fished off Peru (hake, seabass, croaker and searobin) since 1950

Ballón, M

Benites, C

Guevara-Carrasco, R

Wosnitza-Mendo, C

Repository@Hull - Worktribe

HMAP Dataset 16: Peru,South-east PacificPage 1 of 10HMAP Dataset 16Peru, South-east PacificSupporting DocumentationHMAP Dataset 16: Peru,South-east PacificPage 2 of 101. SummaryDataset Title: Peru, South-east PacificLarge Marine Ecosystem: 13: Humboldt CurrentSubject: catch, effort and biological data relating tofour demersal species fished off Peru (hake,seabass, croaker and searobin) since 1950Data Provider: Claudia Wosnitza-MendoInstituto del Mar del Peru (IMARPE)CallaoPeruemail: claudiawosnitza@yahoo.deData Editor: David J Starkey, MHSC, University of Hulld.j.starkey@hull.ac.ukExtent: 6449 recordsKeywords: historical statistics; HMAP; Peruviandemersal fisheries; Humboldt CurrentCitation:(a) The dataset: please cite as follows: M. Ballón, C. Wosnitza-Mendo, R. Guevara-Carrascoand C. Benites, ‘Peru, South-east Pacific’,, in D.J. Starkey & J.H. Nicholls (comp.) HMAPData Pages (www.hull.ac.uk/hmap)(b) Supporting documentation: please cite as follows: M. Ballón, C. Wosnitza-Mendo, R.Guevara-Carrasco and C. Benites, ‘HMAP Dataset 16: Peru, South-east Pacific, SupportingDocumentation’, in D.J. Starkey & J.H. Nicholls (comp.) HMAP Data Pages(www.hull.ac.uk/hmap)HMAP Dataset 16: Peru,South-east PacificPage 3 of 102. Research Context & ObjectivesAlthough Peru is located in tropical latitudes (between 3˚ 23’S and 18˚ 21’S), the sea off itsshores is characterised by the coldness of the waters of the prevailing Humboldt Current. Thisconstitutes one of the main upwelling regions of the world, and is marked by the highest levelof primary production and the greatest fishery based on a single pelagic species (anchovy).This marine ecosystem varies greatly on seasonal, inter-annual (ENSO cycle) and multi-decadal scales. The physical factors which condition the particular climate of this region arethe cold surface current flowing towards the equator, the subsurface moving towards theSouth Pole with its oxygenated undercurrent, the Andes mountains with peaks over 6000metres above sea level, and the south-eastern trade winds, which form part of the SouthPacific Anti-cyclonic gyre. Upwelling determines most of the biological processes in thisecosystem.The pelagic element of this LME has been studied extensively, largely because of thevolatility of the anchovy stock, the scale of the fishery and the alternation in the relativeabundances of anchovy and sardine that has been evident over the last 40 years. As aconsequence, comparatively little scholarly attention has been afforded to the demersalsystem off Peru, even though demand for these bottom-dwelling fish increased to such anextent that landings grew from about 50,000 tonnes in the late 1960s to over 330,000 tonnesin 1978 (see chart below). This impacted upon the health and distribution of the hakepopulation in particular, and with younger individuals taken as they migrated into the fishinggrounds, the stock suffered from overfishing and the fishery was closed in 2002.The aim of this research is to assess the impact that fishing activity has had upon fourdemersal species off the Peruvian coast since c.1950. Focusing on hake, seabass, croakerand searobin, the investigation is designed to establish the extent to which the catching efforthas altered the distribution, diversity and abundance of these species. Among the results ofthe analysis will be a series of targets for the recovery of these species.HMAP Dataset 16: Peru,South-east PacificPage 4 of 103. Primary Source MaterialsThe principal sources of information for this strand of WP2 research are the statistical returnsregarding catches and fishing effort collected by the state’s fishery agencies since the 1950s,and data returned by scientific cruises undertaken since the early 1980s. This evidencefacilitates analysis of the spatial and temporal distribution patterns of the demersal fishassemblages, and the structure of populations, notably in terms of length-frequencies, meanlength, range and maximum sizes. With regard to the changing distribution of hake stocks,some provisional findings are presented on the Visualisations page of the HMAP Data Pageswebsite (http://www.hull.ac.uk/hmap/visualisation). Moreover, the declining trend in the size ofindividual fish taken in the sample cruise data can be discerned in the table below.HMAP Dataset 16: Peru,South-east PacificPage 5 of 104. Metadata: Explanation of Data FieldsThe entries below are outlined as per the field headings of HMAP Dataset 16. An explanationis offered for each field in general terms, and also in dataset specific terms.IDID is the unique, consecutive serial numbers for the complete HMAP database.InstitutionCodeInstitutionCode is the name given to the overall project of which this Dataset forms apart (HMAP).CollectionCodeCollectionCode is the specific HMAP project Dataset reference code (used for OBISreferencing purposes).DateLastModifiedThis is the date when the data were last modified.CASE_STUDYCASE_STUDY is the location identifying description of the Dataset. In this instance:Southeast Pacific demersal fishery off the Peruvian coast.DATASETDATASET is the HMAP project unique Dataset reference.REFERENCEREFERENCE refers to the source of records employed in the research.CitationCitation is the field where the formal attribution is shown for users of the HMAPDatasets to cite; it credits the researchers and editors of a Dataset together with itsdatabase compilers. This citation must be quoted whenever records are referenced oremployed for any purpose.Please quote the relevant citation when using extracts or details from this Dataset: M. Ballón, C. Wosnitza-Mendo, R. Guevara-Carrasco and C. Benites, ‘Peru,South-east Pacific’, in D.J. Starkey & J.H. Nicholls (comp.) HMAP Data Pages(www.hull.ac.uk/hmap)BasisOfRecordBasisOfRecord is the abbreviation applied that indicates whether the record is basedon observations (O), living organisms (L), specimens (S), germplasm/seeds (G),photos (P), or from literature with original basis unknown (D); the HMAP value isgenerally 'O'.OCEAN_REGIONThis field indicates the specific Ocean Region where the Dataset research has beencarried out. If this field shows 'None', then the research reflects activities carried out innon-seaward locations (e.g. in rivers, weir fishing, etc.). In this Dataset, the SouthPacific Ocean region was researched.HMAP Dataset 16: Peru,South-east PacificPage 6 of 10LMEThis field indicates the name of the Ecosystem where the record event occurred. Tofind out more about LMEs (which are confined to continental shelf regions) browsethe Large Marine Ecosystem site (http://www.edc.uri.edu/lme/) where LME GIS datamay be downloaded. In this Dataset, the Humboldt Current region was researched.LME_NUMBERThis field indicates the number of the LME that is shown in the previous field. In thisDataset, the LME number is 13.LATITUDEThe LATITUDE refers to a mean value of the species distribution from surveys andshould be cross referenced with the LONGITUDE field for specific locationdetermination. For this Dataset, this field was calculated from the median position ofall positive hauls during investigative surveys between 1975 and 2000 in order todetermine the position for length-frequency distributions, catch statistics and efforts.The Catch Per Unit Effort (see CPUE field) of surveys refers to median latitude andlongitude during each survey.LAT_PRECISIONThis gives the actual precision of the calculated LATITUDE field. The availableoptions are: Approx Approximate position Estimated Estimated position Exact Exact position Ground Centre Notional centre of the relevant fishing ground Unknown Position not knownLONGITUDEThe LONGITUDE refers to a mean value of the species distribution from surveys andshould be cross referenced with the LATITUDE field for specific locationdetermination. For this Dataset, this field was calculated from the median position ofall positive hauls during investigative surveys between 1975 and 2000 in order todetermine the position for length-frequency distributions, catch statistics and efforts.The Catch Per Unit Effort (see CPUE field) of surveys refers to median latitude andlongitude during each survey.LON_PRECISIONThis gives the actual precision of the calculated LONGITUDE field. The availableoptions are: Approx Approximate position Estimated Estimated position Exact Exact position Ground Centre Notional centre of the relevant fishing ground Unknown Position not knownST_YEARThis field refers to the start year of the beginning of the sampling.EN_YEARThis field refers to the end year of the end of the sampling. Unless the samplingspanned an extensive period, this value is usually the same as the ST_YEAR fieldentry.HMAP Dataset 16: Peru,South-east PacificPage 7 of 10ScientificNameThis field indicates the scientific name of the species under investigation which islinked to the HMAP related FISH BASE database containing detailed informationabout the species that were sampled.ObservedWeightThis field indicates the observed mass of the sample in Kilograms. Where this data isnot available, a value of "unknown" is entered.Catch_NCATCH_N indicates the actual number of specimens sampled for a particular record.Where this data is not available, a value of "unknown" is entered.GENDERThis field indicates the Gender of the species in the sample. The values available areshown as follows: 'M' male 'F' female 'U' unknown 'B' both male and female 'H' hermaphroditeNOTESThe NOTES field gives detailed information specific to a particular record. The detailsare provided to clarify specific entries and where further explanation is required thanis generally provided in this METADATA file. For complete and academicallyverifiable explanations, refer to the published research materials that are indicated inthe REFERENCE field.Abbreviations used in the NOTES field: TR Trawlers PS Purse-Seiners [1] Anuario estadístico pesquero Perú Ministerio de Pesquería [2] IMARPE internal report [3] Report of the second session of the international panel of experts forassessment of Peruvian hake population. March 2004. Bol.Ins. MarPerúVol 21/N° ½ [4] Anuario estadístico pesquero Perú Ministerio de Pesquería (years1970-2003)Vessel_TypeThis field gives a description of the vessel type that was employed in the samplingprocess. The available values (in metric tonnes) range from: Small Trawler < 50 tonnes; main engine < 500 hp Medium Trawler 50 to 150 tonnes; main engine < 1000 hp Big Trawler (factory) > 50 tonnes; main engine > 1000 hp Purse-Seine vessels target species is anchovy with incidental hake catchesHOME_PORTThis is the home port of the fleet employed in the sampling.HMAP Dataset 16: Peru,South-east PacificPage 8 of 10MethodThe METHOD is an indicator of the primary gear used in the fishery; it indicates themeans by which samples were extracted. This is typically the actual method offishing, such as "Bottom Trawl".LengthThe LENGTH field shows the actual species sample length indicated in centimetres(cm). For this Dataset, LENGTH (this field) and FREQUENCY (next field) data of theMerluccius gayi peruanus SPECIES relates specifically to samples from Tumbes3°30' S, Paita 5° S, Salaverry 8° S, and Chimbote 9° S.FrequencyThe Frequency field (regular occurrence) indicates the frequency at which thespecies for the given period occurs and is weighted according to the total annualCATCH_W (next field).NOTE FREQUENCY data of the Paralabrax humeralis SPECIES are poor for the years1969 and 1983 FREQUENCY data of the Paralonchurus peruanus SPECIES are poor for theyears 1963, 1966, 1991 and 1992 FREQUENCY data of the Prionotus stephanophrys SPECIES are poor for theyear 1983 For this Dataset, LENGTH and FREQUENCY data of the Merluccius gayiperuanus SPECIES relate to samples from Tumbes 3°30' S, Paita 5° S, Salaverry8° S, and Chimbote 9° SCatch_WThis field indicates the mass of the catch in metric tonnes (t).NOTE Records (inclusive) from 556389 to 556444 are based on investigative surveysfrom specific vessels (RV Humboldt, RV Olaya, RV SNP-1). The CATCH_W andEFFORT values are not available for these records; the CPUE values are meanvalues derived from data that is weighted to sub-areas. Original data areavailable in IMARPE records. These specific records have CPUE values that areshown in tonnes per square nautical mile (t/nm2). See the CPUE and EFFORTfield descriptions as well.EffortThis field shows the EFORT taken by the fishery and is measured according to thenumber of trips undertaken.NOTE Records (inclusive) from 556389 to 556444 are based on investigative surveysfrom specific vessels (RV Humboldt, RV Olaya, RV SNP-1). The CATCH_W andEFFORT values are not available for these records; the CPUE values are meanvalues derived from data that is weighted to sub-areas. Original data areavailable in IMARPE records. These specific records have CPUE values that areshown in tonnes per square nautical mile (t/nm2). See the CPUE and CATCH_Wfield descriptions as well.HMAP Dataset 16: Peru,South-east PacificPage 9 of 10CPUEThe CPUE field (Catch Per Unit Effort) is expressed in metric tonnes per trip. Seenotes on LATITUDE and LONGITUDE fields for more information.NOTERecords (inclusive) from 556389 to 556444 are based on investigative surveys fromspecific vessels (RV Humboldt, RV Olaya, RV SNP-1). The CATCH_W and EFFORTvalues are not available for these records; the CPUE values are mean values derivedfrom data that is weighted to sub-areas. Original data are available in IMARPErecords. These specific records have CPUE values that are shown in tonnes persquare nautical mile (t/nm2). See the CATCH_W and EFFORT field descriptions aswell.HMAP Dataset 16: Peru,South-east PacificPage 10 of 105. OutputsC. Wosnita-Mando, M. Ballón, C. Benitez & R. Guevera-Carresco, ‘Changes in the distributionarea of Peruvian hake: effect of fisheries’, (in prep.)Enquiries regarding the information contained in this document and the accompanyingdataset should be directed to David J Starkey (d.j.starkey@hull.ac.uk) or John H Nicholls(j.nicholls@hull.ac.uk).

HMAP Dataset 16: Peru, South-east Pacific

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