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

Risk analysis and evaluation
STOCK: Large ostrich foot (Struthiolaria papulosa)
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:
The large ostrich foot code has never been used to report commercial catch; therefore any catch of this
species would be recorded under the generic whelk code. Whelk has been largely taken as bycatch of
established trawl and dredge (oyster and scallop) fisheries in recent years. Whelk was targeted in FMA
7 from 1988/89 to 1997/98, but only a small proportion of this whelk catch was likely to be large
ostrich foot. In addition, due to the nature of catch-reporting obligations for non-QMS species, unless
the bycatch species is estimated to be among the 5 most abundant species taken in a given dredge or
bottom trawl, estimated catches do not have to be reported. The whelk data and consequently any
ostrich foot data therefore are, at best, only indicative of annual catch and of year-to-year catch
variability. Conclusions regarding risk drawn from such data are therefore likely to be highly uncertain.
Table 4: Reported landings (kg) for the fishing years 2002/03 – 2006/07
2002/03 2003/04 2004/05 2005/06 2006/07
Whelk 1,092 5,078 676 243 829
Scallop 185,006 99,965 146,949 171,419 132,118
Oyster 451,335 270,100 267,711 386,014 237,221
Landed catches vary markedly over the five fishing years from as high as 5,078 kg in 2003/04 to as low
as 243 kg in 2005/06 (Table 4). It is uncertain what led to these fluctuations in catch. Catch of whelk
has not followed the same trends as scallop or oyster catch.
Given the variable catch and lack of species-specific reporting, the level of risk to the large ostrich foot
is difficult to assess. MFish should encourage the correct identification and reporting of whelk species
and monitor whelk and large ostrich foot catch. Such administrative steps would provide a better basis
for an assessment of future management interventions, and such action in itself would better meet the
purpose of the Fisheries Act. Should reported catches continue to decline and/or if TACCs of
associated target QMS species are adjusted to higher levels in the following one or two fishing years,
MFish should reconsider management interventions.
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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