{"key":"fd3b3545-7b42-4851-9a33-23ebefed1a67","installationKey":"5ff1c992-5c84-40aa-bd9a-c1743a870c32","publishingOrganizationKey":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","doi":"10.15468/bh42uu","external":false,"numConstituents":0,"type":"OCCURRENCE","subtype":"OBSERVATION","title":"Maritimes Recreational Shark Fishery Derbies","description":"<p>The Maritimes Recreational Shark Fishery has been active since 1993.  Biological data collected from the recreational fishery is used to develop an  assessment of stock status and the general health of the population, particularly that of blue sharks. \n\nShark fishing derbies are held each year in waters off Nova Scotia, usually during the months of July, August and September.  These are commercial or community-sponsored events, and are not sponsored by DFO or the Shark Research Lab.  However, the catches provide excellent samples for scientific examination, and thus all catches are closely monitored.  The species most often caught is the blue shark.  However the occasional thresher or porbeagle shark is also caught.  Shortfin mako sharks are not uncommon in Canadian waters. Other species of shark do occur in Nova Scotian waters, however many of them prefer warmer waters that are associated with the Gulf Stream, or deeper waters which make them unlikely to be caught by recreational anglers. \n\nVersions of the derby data may be restricted to blue sharks only, since that comprises 99% of the catch.  \n\nUsers of records from this data set are advised to contact the PI for additional information prior to inclusion in publications.</p>","language":"eng","homepage":"http://iobis.org/mapper/?resource_id=2955","citation":{"text":"Bowlby H, Joyce W (2021). Maritimes Recreational Shark Fishery Derbies. Fisheries and Oceans Canada. Occurrence dataset https://doi.org/10.15468/bh42uu accessed via GBIF.org on 2026-10-14.","identifier":"http://iobis.org/mapper/?resource_id=2955","citationProvidedBySource":false},"contactsCitation":[{"key":6911160,"abbreviatedName":"Bowlby H","firstName":"Heather","lastName":"Bowlby","roles":["ORIGINATOR"],"userId":[]},{"key":6911161,"abbreviatedName":"Joyce W","firstName":"Warren","lastName":"Joyce","roles":["METADATA_AUTHOR"],"userId":[]}],"lockedForAutoUpdate":false,"createdBy":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","modifiedBy":"crawler.gbif.org","created":"2026-02-12T23:00:25.707+00:00","modified":"2026-02-12T23:01:26.458+00:00","contacts":[{"key":6911160,"type":"ORIGINATOR","primary":true,"userId":[],"firstName":"Heather","lastName":"Bowlby","position":["Aquatic science biologist"],"email":["heather.bowlby@dfo-mpo.gc.ca"],"phone":[],"homepage":[],"organization":"Fisheries and Oceans Canada","address":["Bedford Institute of Oceanography"],"city":"Dartmouth","province":"Nova Scotia","country":"CA","postalCode":"B2Y 4A2","createdBy":"crawler.gbif.org","modifiedBy":"crawler.gbif.org","created":"2026-02-12T23:01:26.428+00:00","modified":"2026-02-12T23:01:26.428+00:00"},{"key":6911161,"type":"METADATA_AUTHOR","primary":true,"userId":[],"firstName":"Warren","lastName":"Joyce","position":["Biologist"],"email":["warren.joyce@dfo-mpo.gc.ca"],"phone":[],"homepage":[],"organization":"Fisheries and Oceans Canada","address":["Bedford Institute of Oceanography"],"city":"Dartmouth","province":"Nova Scotia","country":"CA","postalCode":"B2Y 4A2","createdBy":"crawler.gbif.org","modifiedBy":"crawler.gbif.org","created":"2026-02-12T23:01:26.430+00:00","modified":"2026-02-12T23:01:26.430+00:00"},{"key":6911162,"type":"PUBLISHER","primary":false,"userId":[],"lastName":"OBIS Canada","position":["data management team"],"email":["mary.kennedy@dfo-mpo.gc.ca"],"phone":[],"homepage":[],"organization":"Fisheries and Oceans Canada","address":["Bedford Institute of Oceanography"],"city":"Dartmouth","province":"Nova Scotia","country":"CA","createdBy":"crawler.gbif.org","modifiedBy":"crawler.gbif.org","created":"2026-02-12T23:01:26.431+00:00","modified":"2026-02-12T23:01:26.431+00:00"},{"key":6911163,"type":"ADMINISTRATIVE_POINT_OF_CONTACT","primary":true,"userId":[],"firstName":"Heather","lastName":"Bowlby","position":["Aquatic science biologist"],"email":["heather.bowlby@dfo-mpo.gc.ca"],"phone":[],"homepage":[],"organization":"Fisheries and Oceans Canada","address":["Bedford Institute of Oceanography"],"city":"Dartmouth","province":"Nova Scotia","country":"CA","postalCode":"B2Y 4A2","createdBy":"crawler.gbif.org","modifiedBy":"crawler.gbif.org","created":"2026-02-12T23:01:26.433+00:00","modified":"2026-02-12T23:01:26.433+00:00"}],"endpoints":[{"key":1242617,"type":"DWC_ARCHIVE","url":"https://ipt.iobis.org/obiscanada/archive.do?r=mar_shark_derbies","createdBy":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","modifiedBy":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","created":"2026-02-12T23:00:25.847+00:00","modified":"2026-02-12T23:00:25.847+00:00","machineTags":[]},{"key":1242616,"type":"EML","url":"https://ipt.iobis.org/obiscanada/eml.do?r=mar_shark_derbies","createdBy":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","modifiedBy":"c98a8d0d-cab2-4506-8c0f-c91a5e4996b9","created":"2026-02-12T23:00:25.811+00:00","modified":"2026-02-12T23:00:25.811+00:00","machineTags":[]}],"machineTags":[{"key":33142703,"namespace":"crawler.gbif.org","name":"crawl_attempt","value":"30","createdBy":"crawler.gbif.org","created":"2026-10-12T02:22:06.739+00:00"}],"tags":[],"identifiers":[{"key":463541,"type":"URL","identifier":"http://ipt.iobis.org/obiscanada/resource?r=mar_shark_derbies","createdBy":"crawler.gbif.org","created":"2026-02-12T23:01:26.435+00:00","primary":false}],"comments":[],"bibliographicCitations":[{"text":"Campana, Steven E, Linda Marks, Warren Joyce, Nancy Kohler. 2004. Influence of recreational and commercial fishing on the blue shark (Prionace glauca) population in Atlantic Canadian Waters. CSAS Res doc 2004/069.\nhttp://www.marinebiodiversity.ca/shark/english/document/Derby%20Res%20Doc.pdf","citationProvidedBySource":false}],"curatorialUnits":[],"taxonomicCoverages":[{"description":"Blue and mako sharks","coverages":[{"scientificName":"Prionace glauca","commonName":"blue shark","rank":{"verbatim":"species","interpreted":"SPECIES"}},{"scientificName":"Isurus oxyrinchus","commonName":"mako","rank":{"verbatim":"species","interpreted":"SPECIES"}}]}],"geographicCoverages":[{"description":"Harbours around the coast of Nova Scotia are the starting points for fishing derbies","boundingBox":{"minLatitude":43.69,"maxLatitude":45.906,"minLongitude":-66.131,"maxLongitude":-59.974,"globalCoverage":false}}],"temporalCoverages":[{"@type":"range","start":"1993-08-21T00:00:00.000+00:00","end":"2016-08-22T00:00:00.000+00:00"}],"keywordCollections":[{"thesaurus":"GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type.xml","keywords":["Occurrence"]},{"thesaurus":"GBIF Dataset Subtype Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_subtype.xml","keywords":["Observation"]}],"project":{"title":"Shark Derbies","contacts":[{"type":"CONTENT_PROVIDER","primary":false,"userId":[],"lastName":"DFO Maritimes Region","position":[],"email":[],"phone":[],"homepage":[],"address":[]}],"awards":[],"studyAreaDescription":"Recreational shark derbies are held during summer months at various locations around the coast of Nova Scotia. Blue sharks are usually caught using squid, mackerel or herring as bait and in water depths of at least 100 feet (preferably deeper), although the bait is fished relatively near the surface.  Some fishers chum the water first to attract any sharks that are nearby.  Water temperatures above 18 degrees Celsius are usually associated with greater catches.","designDescription":"Derby participants must first apply to Fisheries and Oceans Canada(DFO)for a licence.  Once a licence has been obtained participants download their Recreational Shark Fishery Summary Document (fishing log), instructions for completing the fishing log, or an example of a completed log.  Additional information (including how to identify the species of your shark or determine its sex) is also provided.\n\nFor the purpose of scientific data collection, participants of the recreational shark fishery are required to provide information on length, weight, sex and location of every shark that is caught, whether or not it is landed or released.  By monitoring trends in this data from year to year, and in conjunction with the more detailed information collected at the shark derbies, the scientists at the Shark Research Laboratory are able to detect population-level changes which are indicators of low stock abundance or overfishing.  Biological indicators such as the size composition, size at sexual maturity and catch per fishing effort are particularly useful for detecting problems with the population.  While there are social and economic benefits to a healthy shark fishery, the fishery must be sustainable over the long term.  In other words, the populations of each of the shark species must be conserved at safe levels.","relatedProjects":[]},"samplingDescription":{"studyExtent":"Shark derbies are held annually at various ports around the coast of Nova Scotia.  Boats tend to depart the port around dawn and return late afternoon to participate in the weigh-in. The exact location where sharks are captured is not recorded and a 20 km radius around each port has been used in this dataset as a proxy for the fishing area.","sampling":"The number of shark derbies and participants has been increasing ever since their inception, and biological data has been collected at each of them every year.   Most of the sharks caught during the derbies are landed rather than released.  It is from these animals that lengths, weights, sexual maturity and stomach contents can be recorded and analyzed.  Vertebrae are sometimes collected for age determination.  \n\nBeginning in the summer of 2006, the rules for all derbies were changed.  Under the new rules, all blue sharks less than 240 cm (8 feet) are to be released alive, preferably after tagging.  Tagging is voluntary, but is strongly encouraged by DFO Science, and a tagging kit is provided to all fishing captains before the start of the derby.  Along with tag number, derby participants report information such as length, sex, location and water temperature on their tagging forms, which are turned in to DFO biologists at the end of each derby fishing day.  Sharks larger than 240 cm (8 feet) can continue to be landed, as can sharks of any size other than blue sharks.  Live release of porbeagle sharks, which have been listed as endangered by COSEWIC, is also encouraged.  The large numbers of sharks tagged by derby participants will be of great scientific value to DFO Science, since the recapture rates will be used to provide better estimates of blue shark mortality rates. \n\nNote that the rules for landing sharks at derbies were changed in 2006, which resulted in fewer sharks being landed.\n\nAll sharks were caught using rod and reel.","qualityControl":"Scientific names associated with resource occurrence records have been mapped to recognized standards - marine taxa have been mapped to the World Register of Marine Species (WoRMS). The WoRMS codes, the AphiaIDs have been included as LSIDs in the occurrence record DwC field scientificNameID","methodSteps":["The source dataset does not include the location where the individual sharks were caught. The only location information is the placename where the derby was held. Coordinates were chosen based upon the place name in the Canadian Geonames database (CGNDB).\n \nThe original data records collected as part of the derby are archived by the Fisheries and Oceans Canada Maritimes Region. A subset of this dataset including capture information for blue sharks only was provided to OBIS Canada and queries were run to extract Darwin Core (DwC) records in the required IPT format. \n\nUsers should contact the data provider if they wish to access the source database.","Life stage is not included in these data records however for landed sharks at the derbies, the life stage is indicated by the length of the shark.  Female blue sharks reach sexual maturity at 2.2 – 3.2 m and males at 1.8 to 2.8 m.  Non-landed sharks (those tagged and released)could be of any life stage.\n\nThe DwC dynamicProperties field contains information on weight (kg) and length (cm) of individual sharks. \nDresswt = dressed weight and indicates that the shark was weighted after being gutted/dressed\nFlcurved = fork length curved and indicates that the measuring tape followed the dorsal curve of the body and ran from the tip of the snout to the fork of the tail.","Version 1 of this dataset contains records from derbies held between 1993 and 2013. Version 2 includes addition of records from the 2014 derbies.\nVersion 3 includes addition of records from the 2015 and 2016 derbies\n\nVersion 1 is restricted to blue shark records only.","DwC fields populated as follows:\nCollectionCode ='SharkDerbies' in Version1 with addition of 'SharkDerbies_2014' in Version2.\nDynamic properties includes the following keyword pairs: DressedWeight; ForklengthCurved; RoundWeight; TotalLengthCurved; InterDorsalLength; LateralJawGap; StomachContents; VisualObservations. DynamicProperties values may include 'NA'."]},"countryCoverage":[],"collections":[],"dataDescriptions":[{"name":"Shark Derby home page","charset":"ascii","url":"http://www.dfo-mpo.gc.ca/species-especes/sharks/index-eng.html","format":"HTM"}],"dataLanguage":"eng","additionalInfo":"marine, harvested by iOBIS","pubDate":"2021-04-16T00:00:00.000+00:00","maintenanceUpdateFrequency":"UNKOWN","maintenanceDescription":"","license":"http://creativecommons.org/licenses/by/4.0/legalcode","dwca":{"coreType":"http://rs.tdwg.org/dwc/terms/Occurrence","extensions":[],"modified":"2026-07-10T12:12:54.953+00:00"},"approximateCounts":{"occurrenceCount":3873}}