Illegal fish dumping charges have been laid over the activities of another Korean Oyang fishing boat.

The Ministry of Primary Industries (MPI) says it has laid eight charges against the foreign charter vessel Oyang 77 over illegally dumping fish at sea.

One of the charges relates to the dumping of a large basking shark, the second largest fish in the world.

Oyang 75 - also owned by Korea's largest fishing company Sajo Oyang - is before the courts facing 26 fisheries charges. It was brought to New Zealand last year to replace Oyang 70 which sank two years ago pulling in an overweight net, killing six men.

The Oyang boats are chartered from Sajo Oyang by its Christchurch based shell company, Southern Storm (2007) Ltd.

MPI says eight charges were laid against the skipper and three charges against the factory manager at Christchurch District Court last week and these were served late yesterday.

"We take all allegations or evidence of breaches very seriously," says MPI Deputy Director-General Scott Gallacher.

"We investigate thoroughly and methodically, and where there is sufficient evidence we will prosecute."

A joint ministerial inquiry into foreign charter fishing boats earlier this year reported that Korean flagged vessels were damaging New Zealand's international reputation.

The New Zealand fishing industry has a good level of compliance with regulations, but breaches like those alleged against the Oyang boats occur from time to time, Gallacher said.

"Commercial fishing relies largely on the honesty of fishers and their understanding that complying with regulations ensures the sustainability of the resource they depend on for their business."

Gallacher says while these types of investigations take time and require attention to detail and a significant amount of work, it is important that people do not feel that their information is unimportant or ignored.

"We urge people to come to us if they have any evidence or suspicion of this type of breach. We will investigate."

In any instance where there proves to be evidence that wrong-doing has occurred, then a prosecution is likely, he said.

The two men charged were due to appear in court in July.

Korean boats have also been accused of systemic human rights and labour rights abuses toward their mainly Indonesian crews.