Information briefs and risk analyses for species under consideration ...

Risk analysis and evaluation
STOCK: Hammerhead shark (Sphyrna zygaena)
Severity/likelihood risk analysis:
Generic objective 1: Risk to maintaining the potential of the stock to meet the
reasonably foreseeable needs of future generations.
Analysis: There is uncertainty associated with the reporting of species such as hammerhead shark. The
available information suggests very small amounts of catch. However as most of the catch reported is utilised
and therefore has unit value to fishers it is unlikely that substantial misreporting is occurring. It is of concern
that recreational catches appear to have declined.
In the South West Pacific the species is listed on the IUCN Red List as having least concern. Nevertheless
NIWA suggests hammerhead shark may warrant full protection because of its particular biological
characteristics.
The impact of maintaining the existing regime in the short term is likely to be minor. Accordingly no
management intervention is currently necessary and the species should retain its Schedule 4C listing. Prior to
re-considering hammerhead shark for introduction ito the QMS an assessment to consider protecting the species
as recommended by NIWA should be undertaken. This might be achieved by evaluating the species against the
proposed prohibited utilisation standard as discussed in the draft NPOA Sharks.
Severity of impact (low, medium or high) : Low
Likelihood of impact (low, medium or high) Low:
Risk score (1-9) :1
Generic objective 2: Risk to avoiding, remedying or mitigating any adverse effects of
fishing on the aquatic environment.
Analysis: The risk of adverse effects on the aquatic environment is unknown. Most catch of hammerhead shark
is taken by bottom trawling but only as a consequence of fishing for QMS species.
Little is known of habitat interaction apart from potential impacts on aggregations of juveniles in areas such as
the Hauraki Gulf.
Severity of impact (low, medium or high) : Low
Likelihood of impact (low, medium or high) : Low
Risk score (1-9) :1
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