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

14 Carpet shark is not a commercially targeted species – its capture is generally a result
of incidental bycatch. Carpet shark is currently managed as an open access non-QMS
species. There does not appear to be any commercial demand specifically for carpet
shark although carpet shark caught is often utilised for its fins. To some extent, the
combined total allowable catch (TAC) limits of the target species may be limiting the
total catch of carpet sharks.
15 Carpet shark landed catch includes both the catch that is utilised and fishers’ estimates
of discarded catch.
Commercial fishing method
16 Carpet shark is an incidental bycatch from the commercial fishing methods of bottom
trawling and set netting. There is also a small amount of bycatch from bottom
longline and rock lobster potting methods.
Commercially landed catch
17 Estimated catch data from catch effort returns, together with corresponding landing
information, provides the catch data set for carpet sharks.
18 A number of factors have resulted in some uncertainty within the data set for carpet
shark. As there are many shark species within the New Zealand EEZ, and some of
these are encountered relatively infrequently, there are sometimes instances where
species are mis-identified and consequently mis-reported. Approximately 4-5% of the
annual commercial shark catch is reported against generic stock codes such as ‘other
sharks and dogs’ (OSD). In addition, there has been at least one occasion where
estimated catch of cardinal fish (CDL) has been inaccurately recorded as carpet shark
(CAR). The following analyses should be interpreted with these data uncertainties in
mind.
19 Reported landings of carpet shark increased to 68 tonnes in the late 1980s, dropped to
2 tonnes in the early to mid 90s, and have since increased to record highs of more than
200 tonnes (Figure 3). The increased landings of carpet shark between 1988-91 were
probably due to the operation of a shark liver oil fishery during this time period,
which ceased around 1994 (Figure 3).
20 Since 2002, landings of carpet shark steadily increased from below 50 tonnes to over
245 tonnes in the 2006/07 fishing year (Figure 3). Landings by carpet shark fishstock
code † show a corresponding catch increase from three fishery management areas
(FMAs 3, 4 and 5) over the same time period (Figure 4). However, there has not been
a corresponding increase in catch in the target fisheries that take carpet shark as
bycatch within these FMAs. Other than changes in catch reporting trends, it is unclear
why the catch of carpet shark has significantly increased in recent years.
† Carpet shark fishstock codes relate to standard fisheries management areas e.g. CAR 1 = FMA 1)
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