The detection of a shellfish disease in mussels in the South Island has led to Canada banning imports of live New Zealand greenshell mussels.
The Ministry for Primary Industries says the ban follows the detection of a single organism of Perkinsus olseni in September.
The disease is endemic in shellfish in the North Island, but not in mussels, and is not a food safety risk.
A spokesperson for the ministry says since November 2013, New Zealand has only sent one 88kg consignment of live greenshell mussels to Canada worth less than $1000.
Most of the greenshell mussel trade with Canada involves frozen mussels and this is unaffected by the ban.