Over the past few summers there have been higher than usual numbers of fish deaths on some Marlborough salmon farms. It is likely the increased death rates are due to a range of factors. These may include environmental factors (like water temperature), management practices at affected farms and exposure of salmon to bacterial infection.Two particular bacteria have been detected in samples from Marlborough salmon farms. These are a Rickettsia-like organism (an Unwanted Organism) and a bacterium called Tenacibaculum maritimum. To date, the Rickettsia-like bacterium has not been found on salmon farms outside of Marlborough. For this reason, MPI is enacting some legal controls on salmon farming activities to help prevent the spread of this bacterium outside the two affected Sounds.
Surveillance Programmes, Publications