Commercial catch: sharks and rays

  • Ray

    New Zealand waters have at least 117 species of chondrichthyans (sharks, rays, and other cartilaginous fish species). They are particularly vulnerable to overfishing because they are long-lived, mature slowly, and have a low reproductive rate. Chondrichthyans are important for healthy ocean ecosystems, and reporting their commercial catch and bycatch helps us understand the sustainability of our fisheries.

    We classified Commercial catch – sharks and rays as supporting information.

    Key findings

    Fisheries catch more than 70 chondrichthyan species (including protected species) every year, either intentionally or as bycatch.

    Between 2005 and 2014:

    • most of the targeted shark and ray species catch (by weight) in commercial fisheries was from species managed by the quota management system (QMS)

    Between 2005 and 2015: 

    • reported discards of sharks and rays ranged from 16 percent to 27 percent of total catch.

    Between 2010 and 2014: 

    • spiny dogfish, a QMS species, was the most-caught targeted species (29 percent of catch by weight)
    • basking shark (165 tonnes) and spinetail devilray (24 tonnes) were the most-caught protected species over the 2010–14 period.

    Figure 1

    Note: Only species with more than five tonnes of aggregated catch are included. Excludes non-target and protected species catch. QMS – quota management system.

    Figure 2

     

    Note: Years are fishing years. Only species with more than five tonnes of aggregated catch are shown. QMS – quota management system.

    Figure 3

    Note: Years are fishing years. The hammerhead shark is a non-target species while the spinetail devilray and the basking shark are protected species since 2010. Total five-year catches of protected species are estimated and scaled up from numbers of animals reported on protected species for the four years 2010–11 to 2013–14.

    Figure 4

    Note: ‘Retained’ includes all landings where the primary landed state is not ’fin only’, including those processed for livers. (When a fish type is landed in more than one state (eg fins only and whole), the state with the biggest tonnage is called the primary landed state.) ‘Discarded’ refers to non-QMS species not processed at all or spiny dogfish discarded under Fisheries Act 1996 schedule 6 provisions (may be alive or dead). ‘Fin only’ are landings reported with fins as the primary landed state. Fins can only be harvested from dead animals; removing fins from live animals is banned in New Zealand. ‘Released’ refers to live animals released under the schedule 6 provisions (Ministry for Primary Industries, 2014b).

    Definition and methodology

    Chondrichthyan species (sharks, rays, and other cartilaginous fish species) have diverse ecological roles, including as apex predators (eg great white sharks), plankton feeders (eg basking sharks), or bottom feeders (eg spiny dogfish).

    Reported catch includes landings (both intentional and as bycatch), discards, and live release of chondrichthyan species (mainly sharks and rays). Because discarded fish are unlikely to be alive and the survival rate of animals released alive is not known, this information has been aggregated with landings. Under-reporting of protected species bycatch by commercial fishers introduces a bias in the estimates. This can be compensated to a degree in fisheries that have sufficient observer coverage (enough observers for the number of vessels). Observer coverage varies across our commercial fisheries (Ministry for Primary Industries, 2014a).

    Cumulative catch for QMS, non-QMS, and non-target species excludes species with less than 5 tonnes of aggregated catch. Cumulative catch of protected species (basking shark and spinetail devilray) for 2010–14 are estimated and scaled up from numbers of animals reported on protected species forms for the four years 2010–11 to 2013–14 (Ministry for Primary Industries, 2016).

    We also report on the proportion of shark catch discarded each fishing year from 2005 to 2014/15. This tells us whether fisheries use caught fish efficiently. These data are self-reported and likely to overestimate use of the species (Ministry for Primary Industries, 2014b).

    This measure covers the New Zealand exclusive economic zone and territorial sea.

    The commercial fishing year for most fish stocks goes from 1 October to 30 September, but some fish stocks have a fishing year of 1 April to 31 March.

    Data quality

    Topic  Classification Relevance Accuracy
    Marine species, taonga species, and genetic diversity Supporting information

    relevance-indirect
    Indirect

     Image, Medium accuracy.
    Medium

    See Data quality information for more detail.

    References

    Ministry for Primary Industries (2014a). Aquatic environment and biodiversity annual review 2014. Retrieved from www.mpi.govt.nz.

    Ministry for Primary Industries (2014b). National plan of action for the conservation and management of sharks 2013. Retrieved from www.fish.govt.nz.

    Ministry for Primary Industries (2016). Aquatic environment and biodiversity annual review 2015. Compiled by the Fisheries Management Science Team. Retrieved from www.mpi.govt.nz.

    Archived pages

    See Commercial catch: sharks and rays (archived October 2016).

    Updated 27 October 2016

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