The rezoning of 10 ocean beaches and headlands to allow recreational fishing permanently has effectively halved top-level protection along the state's coast, the NSW Nature Conservation Council says.

The Berejiklian government will allow shore-based fishing along 44 kilometres of four sanctuaries - out to 100 metres - at the Cape Byron, Solitary Islands, Port Stephens-Great Lakes and Batemans marine parks.

“Following a five-year amnesty on compliance action with regard to recreational line fishing from ocean beaches and headlands zoned sanctuary, these changes now bring certainty for our state’s fishers," Geoff Allan, director-general of fisheries, said in a statement.

"It is a fun activity for the entire family, and supports regional communities," he said, noting about 1 million people fish at least once a year in NSW.

But environmental groups decried cuts to the highest-level protection along the coast from a previous length of 87 kilometres.

“This decision is a blow for marine conservation and for coastal communities whose economies rely on marine parks and the presence of a healthy marine environment," Daisy Barham, campaigns director at the Nature Conservation Council, said.