Aquatic Environment and Biodiversity Annual Review 2012

AEBAR 2012: Non-protected bycatch
Figure 5.11 (from Hobday et al.): Diagrammatic representation of the hierarchical risk assessment
process where activities that present low risk are progressively screened out by assessments of
increasingly high data content, sophistication, and cost.
5.4.3.2. Qualitative (Level 1) risk assessment
Rowe (2010) summarised an expert-based, qualitative (Level 1) risk assessment, commissioned by
DOC, for the incidental mortality of seabirds caused by New Zealand fisheries. The main focus was
on fisheries operating within the NZ EEZ and on all seabirds absolutely or partially protected under
the Wildlife Act 1953. New Zealand flagged vessels fishing outside the EEZ were included, but risk
from non-NZ fisheries and other human causes were not included.
The panel of experts who conducted the Level 1 risk assessment assessed the threat to each of 101
taxa posed by 26 fishery groups, scoring exposure and consequence independently according to the
schemas in Tables 5.9 and 5.10 (details in Rowe 2010b). The risk for a given taxon posed by a given
fishery was calculated as the product of exposure and consequence scores. Potential risk was
estimated as the risk posed by a fishery assuming no mitigation was in place, and residual risk (called
“optimum risk” by Rowe 2010b) was estimated assuming that mitigation was in place throughout a
given fishery and deployed correctly. The panel also agreed a confidence score for each taxon-fishery
interaction using the schema in Table 5.11.
Table 5.9: Exposure scores used by Rowe (2010) (modified from Fletcher 2005, Hobday et al 2007)
Score Descriptor Description
0 Remote The species will not interact directly with the fishery
1 Rare Interactions may occur in exceptional circumstances
2 Unlikely Evidence to suggest interactions possible
3 Possible Evidence to suggest interactions occur, but are uncommon
4 Occasional Interactions likely to occur on occasion
5 Likely Interactions are expected to occur
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