The last stock assessment for Papanui Inlet and Waitati was in 2007. In Waitati Inlet for 2007 the

biomass of juvenile cockles (>2

-18 mm) has increased from 2002 and 2004 levels but remains well-34 mm) cockles has also increased over 2002 and

below figures for 1992. The biomass of adult (19

2004 levels but is lower than that recorded in 1998. The biomass of large adult (L35 mm) cockles is

the lowest since 1992, and the biomass of cockles L30 mm is the lowest since 1998.

No size limit has been set for COC 3. However, commercial fishers currently target cockles between

28-34 mm, and >38 mm. In Waitati Inlet, the estimates of CAY for this size category are above

current catch levels and recent reported landings. Furthermore, CAY estimates for the area of the inlet

where commercial fishing currently occurs are also above current catch levels and recent reported

landings. Catch levels higher than recent reported landings would be required to move the stocks in

the inlets towards a size that will support the maximum sustainable yield.

Cockles recruit to the spawning stocks in the Otago area at a length of about 18 mm shell length. The

harvested beds may receive spat from other areas. For these reasons, and because of the low

harvesting levels, the risk of recruitment overfishing is probably low.

Cockles recruit to the spawning stock on Snake Bank at a size of approximately 18 mm shell length.

The Snake Bank cockle population may also receive spat from other beds in the harbour. Therefore, at

the current harvest size (about 30 mm shell length) there is probably a low risk of recruitment

overfishing the Snake Bank population, even at high levels of fishing pressure. The risk of recruitment

overfishing, however, increases as the average size of cockles harvested decreases.

The recruited biomass of cockles (> 30 mm shell length) on Snake Bank declined from over 2000 t in

the early 1980s to about 700 t in the early 1990s. It has since fluctuated between about 500 and 1500 t

without apparent trend, falling to particularly low levels (< 500 t) in 2001 and 2002. There has been a

large increase (78%) in recruited biomass on Snake Bank since the last survey in 2006, but the 2007

length frequency distribution suggests that the recruitment of juveniles (under 20 mm SL) has been

poor compared with recent years, and this could lead to reduced levels of adult recruitment to the

fishery over the next year or two. Before October 2002 (when COC 1A was introduced to the QMS),

the sum of the daily catch limits (584 t), and average landings between 1989

–90 and 2001–02 (457 t)

both greatly exceeded estimates of MAY (max

The May 2017 Fisheries Plenary Report summarises fishery, biological, stock assessment and stock status information for 83 of New Zealand’s commercial fish species or species groups in a series of Working Group or Plenary reports. Each species or species group is split into 1-10 stocks for management purposes. COC3

The May 2014 Fisheries Plenary Report summarises fishery, biological, stock assessment and stock status information for 82 of New Zealand’s commercial fish species or species groups in a series of Working Group or Plenary reports. Each species or species group is split into 1-10 stocks for management purposes. Cockles introduction (COC)