This figure, based on thorough analyses of independent Government observer records, discredits claims elsewhere that the annual total catches could be more than double what are being officially reported, he says.
“Some media reports on the draft results include input from Auckland Business School Research Fellow Dr Glenn Simmons. Their analysis assumed discard rates of 20-50 percent in recent years.
“The observer-based estimates by New Zealand’s reputable science body, NIWA, shows that for every kilogram of reported deepwater target catch, 0.07 kg is estimated to be discarded. We note that New Zealand law requires all discarded catch to be reported.
“NIWA have analysed observer and vessel reported catch data spanning the 22 year period 1991-2013, for six of the main deepwater fisheries, and estimated a discard rate of 6.6 percent, not 20-50 percent,” he says.
In the last five years of data for key target fisheries analysed, the discard rate dropped to 4.1 percent.
Discards are all fish (target and non-target) or invertebrates that are returned to the sea whole, for a variety of reasons, during fishing. Estimates of quantities of fish lost from the net at the surface or during retrieval are included as discards in NIWA's analyses, Pankhurst says.
Deepwater fisheries comprise around 80 per cent of New Zealand’s total annual catch.
Click here for Summary and NIWA Reports.
For more details, click this link to NIWA's data.
