The Ministry for Primary Industries says there is no proof that illegal fishing has been taking place in a protected area off the coast of Banks Peninsula.
The Earthrace group claimed that a number of fishing vessels were trawling and net fishing over 10 days in January in a marine mammal sanctuary there
Earthrace said it saw seven incidents during a surveillance operation.
The ministry said the group's evidence was considered and skippers of concerned vessels were interviewed, as well as assessing GPS vessel coordinates.
Spokesperson Scott Gallacher said there is no proof that any of the parties breached fisheries law.