Maui is the world's rarest and smallest marine dolphin, only found off the west coast of the North Island in relatively shallow waters.
Moana and Sanford CEOs Carl Carrington and Volker Kuntzsch said they're taking action to reduce the fishing-related threats from the Maui's known habitat range.
The range runs from Maunganui Bluff in the north to the Whanganui River mouth in the south and out to a depth of 100m.
"Over time we will extend the fishing exclusion out to the 100m depth across the Maui habitat, to remove set netting and trawling from their zone, and we will also increase the amount of monitoring on vessels."
Sanford Ltd has the largest catching presence along the west coast of the North Island.
Moana New Zealand is a significant west coast quota owner and leases catching rights to contract fishers.
Kuntzsch said the companies understand that the initiatives will adversely affect independent fishers who also catch in this area.
"Several of whom lease catching rights and have long-standing business relationships with us."
The Sanford CEO said some of these fishers will find themselves in very difficult situations and be financially challenged by their decision.
"We have been meeting with them and commit to continuing to stand alongside them if they choose to transition to more dolphin-safe methods such as long lining."
Kuntzsch said they were committed to working with all west coast fishers and groups.
"We're also looking to the Government to support this plan by finding ways to assist fishers to transition to dolphin-safe fishing methods, so the commitments we're leading with are adopted by all fishers across the whole Maui habitat."
The companies feel they have a role to play in protecting the mammals.
"Our livelihoods depend on what's out there in the oceans, and that does not only mean on the species we catch, but the health of the whole ecosystem."