The commercial fishing industry is asking for some of the measures put in place to protect Hector's dolphins to be relaxed.
Supporters of the rules, which came into play last October, say without them our dolphins will go from endangered to extinct.
Fewer than eight thousand Hector's dolphins remain and its cousin the Maui dolphin is critically endangered with just more than a 100 left.
Kirstie Knowles, a conservation advocate says these rules are needed to protect the on-going survival of these dolphins.
“They are very, very much in trouble and the estimates from science is telling us that we cannot afford to lose a single one to fishing related deaths,” Ms Knowles says.
It is a view former Minister of Fisheries Jim Anderton supported. Last year he banned set netting, trawling and drift netting in some coastal waters and restricted their use in others.
Today at the high court in Wellington, lawyers for commercial fishing interests sought to have some of Mr Anderton's decisions set aside, so they can be reviewed by current Minister of Fisheries Phil Heatley.
Fishermen says Mr Anderton was mis-informed and as such could not balance the interests of both parties.
Ms Knowles says Mr Anderton’s actions were extremely important to protect the dolphins.
“They were the most significant measures in about twenty years to protect the Hector's and Maui dolphins,” she says.
The regulations are projected to cost 300 jobs and $80 million dollars over five years.
Industry parties’ say Mr Anderton's rules were one of the most extreme, arbitrary and unfair set of decisions that have ever been made by a Minister of Fisheries in New Zealand.
Conservationists say the cost to commercial fishing is nothing compared to the cost of losing a species.
The case is expected to take three days.
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