Traditional Māori fishing practices are being touted as one of the "keys" to rejuvenating marine life in the heavily-degraded Hauraki Gulf.

Richelle Kahui-McConnell, who was involved in developing the Sea Change marine spatial plan, said voluntary methods of protection - as used by Māori for generations - based around experience and education were more effective than strict laws.

"When you set limits, and sizes, people will take up to those limits, whether they need it or not," said Kahui-McConnell, of Ngāti Maniapoto.

"Then we get people throwing back a dozen baby fish with half of them dying from trauma, or