The past three months have involved firstly an audit of fish losses and damage, an investigation into likely cause, acquiring the best expert mooring advice possible for the farms return, repairing the cage infrastructure and attendant grow-out nets and then preparing the optimal and reliable mooring array for the farms return.
The return of the farm was also timed to coincide with supportive tides.
Damage and fish losses were largely covered by insurance; however the major loss was in very small fish, only 3 months in the seawater and their escape results in an opportunity loss next autumn when they would have reached harvest size. Some anecdotal reports suggest that some lucky fisherman have been able to benefit from the loss of the young fish. However it is likely that most would not have survived the lack of feed and natural predators in the Sounds area. Fortunately the company has been able to mitigate the fish loss with additional smolt stocks though the timing of their grow-out is slightly later.
The investigation into the cause has involved previous mooring consultants to the Company, additional independent experts and insurance assessors. Their conclusions have not found a simple single cause. Rather the likelihood that a range of factors contributed to excessive pressure on one section of moorings. The extensive array of 31 moorings, both block and screw anchors, did not evenly spread the load and this resulted in the failure of some initial mooring lines. This then allowed the farm to skew across the prevailing current, increasing the mooring load with a cantilever effect resulting in a cascade of mooring line breakages.
In looking to ensure this event will not happen again, the company has insisted on increased redundancy in the mooring system, has implemented the latest expert advice towards a single array of screw anchors only (some 34) and most importantly added in a tensioning management plan utilising chain connections designed to ensure that mooring loads are always evenly distributed to prevent a repeat of the cascade effect that occurred in March.
TheFishSite News Desk
NZ King Salmon Farm returns safe and sound
NEW ZEALAND - The NZ King Salmon Co Limited announced today the successful return of its Te Pangu farm to its Tory Channel site following the mooring slippage in early March.
NZ King Salmon Farm returns safe and sound - NEW ZEALAND - The NZ King Salmon Co Limited announced today the successful return of its Te Pangu farm to its Tory Channel site following the mooring slippage in early March.