DOI: 10.5061/dryad.8sf7m0csr
title: Data from: Hazard and catch composition of ghost fishing gear revealed by a citizen science clean-up initiative

description: Ghost fishing, the continued catch of fishes and invertebrates by lost
 fishing gear, represents an animal welfare issue as well as a waste of
 both potential food and ecosystem resources. Fishing gear is lost by both
 commercial and recreational fishers, and management authorities often lack
 an overview of gear loss and subsequently potential impact on coastal
 populations. To investigate the hazard and catch composition of lost
 fishing gear along the Norwegian coast, recreational divers in
 collaboration with scientists conducted systematic reporting of retrieved
 lost fishing gear. Through this citizen science project, a total of 12,101
 gear items were retrieved and reported, including traps, gillnets and fyke
 nets. Combining both data on the catch ratio of the gear and its relative
 quantity, we identified the five most hazardous gear types to be parlor
 traps, gillnets, fyke nets, wrasse traps and square collapsible traps. The
 parlour trap was the most hazardous trap, due to high catchability and
 quantity. The correct classification of gear type could not be confirmed
 in 2.8 – 6.1 % of the pictures taken by divers, depending on reporting
 format, and divers reported the wrong gear type in 1.4 % of the reports.
 Brown crab (Cancer pagurus) was the species most often found in retrieved
 gear. Furthermore, the vulnerable species European lobster (Homarus
 gammarus) and Atlantic cod (Gadus morhua) were also common. These results
 can inform future clean up-initiatives and management responses to ghost
 fishing, including preventive measures against gear loss and gear
 restrictions and customization.
description: Data was collected by recreational divers when retrieving lost
 fishing gear along the Norwegian coast between June 2015 – June 2020. All
 diver reports included a photograph of the retrieved gear, and all photos
 and forms were quality checked by the authors to check if the three
 different gear types (traps, gillnets and fyke nets) were correctly
 identified. All photos of traps were checked and classified into nine
 different trap-types: parlour trap, round collapsible trap, square
 collapsible trap, wooden trap, large square trap, circular kelp forest
 trap, crayfish trap, wrasse trap and other traps. “Other traps” include
 traps that could not be categorized into the eight trap types, for
 example, because they were homemade. Data were reported in two different
 ways within the period. From June 2015 to December 2018, paper forms with
 pictures were sent to the Norwegian Diving Association and then to the
 Institute of Marine Research either by mail or e-mail. These reports
 included depth and GPS coordinates for the retrieved gear. From September
 2017, a mobile app report system, “Fritidsfiske” (“Recreational fishing”),
 was launched by the Norwegian Directorate of Fisheries. Data reported
 through the app until June 2020 is included. Within the app, divers could
 deliver reports connected to their diving club. After an app update in
 March 2019 divers that were associated with a diving club supplied more
 detailed reports than other participants. All diver reports included GPS
 coordinates for the retrieved gear. However, detailed reports also
 included information on depth, bottom conditions, slope, presence of rope
 and buoy, and whether there were alive or dead animals found in the
 equipment. Catch was reported as number of live and dead individuals
 separately within five categories: brown crab (<em>Cancer</em>
 <em>pagurus</em>), European lobster
 (<em>Homarus</em> <em>gammarus</em>), wrasse
 family (Labridae), Atlantic cod (<em>Gadus</em>
 <em>morhua</em>) and other fish.
description: All data files are text files. 
 Gear and trap type, time, depth, coordinates 
 This dataset contains data on all gear retrieved by divers where
 the gear type could be verified. The coordinates are given in decimal
 degrees. They have been reported in different formats and
 transformed. Rope, buoy,
 bottom conditions and slope This dataset contains
 data on presence of rope, buoy, bottom conditions and slope by gear type.
 The data is from all gear retrieved by divers and reported in the app
 after the app update that allowed divers to supply more detailed
 reports. Catch data
 This dataset contains data on all reported catches
 (alive and dead) by gear or trap type. Data herein is retrieved by divers
 and reported in the app after the app update that allowed divers to supply
 more detailed reports.