The Department of Conservation (DoC) has tightened permit conditions for commercial shark cage diving on Stewart Island/Rakiura and will increase monitoring.
The shark cage diving season begins today and DoC says it will continue watching the island's two cage diving operators to ensure they're not harming sharks or putting people at greater risk.
The department says both operators are on their last warning after one of them breached conditions last season by using throw bait and, if either operator breaks the conditions again this season, they will lose their permit.
DoC introduced permits for cage diving last year; the activity had been unregulated until then.
Operators are now limited to using one vessel a day.