Hospitals will maintain emergency and essential services during the strike, but some services will be deferred.
The strike comes after negotiations facilitated by the Employment Relations Authority yesterday failed to resolve the pay dispute.
DHBs spokeswoman Helen Mason yesterday thanked those working through the industrial action.
"Essentially not having 70 per cent of your workforce in the workplace will be a significant challenge ... you don't address that easily."
She said safe access to healthcare would be available for those who need it during the strike.
People should not delay seeking medical treatment and should go to hospital if it was urgent.
The New Zealand Nurses' Organisation (NZNO) has 1500 members at the Bay of Plenty DHB and said it was likely more than 500 would strike today.
Others will work to ensure life-preserving services continue at Tauranga and Whakatāne Hospitals.
Angela Neil, the NZNO organiser for the Bay of Plenty DHB, told the Bay of Plenty Times no nurses wanted to disrupt services.
"It was a choice that they've been forced into … most of them will be saying that they would do anything to avoid this, but taking lower pay rises and being overworked hasn't really worked has it? Nobody's listened."
She said NZNO members had been receiving "massive support".
"I think everyone knows how hard nurses have been working; I think they know that they've been understaffed for a very long time."
Neil said there was no money for all the extra commitments nurses take on – qualifications, new techniques and specialities that they work on and learn in their spare time.
"I've been a nurse all of my life and I just think it's time that nurses got paid for their skills and their expertise."
She said NZNO delegates would walk night staff off the job at 7am and support those members who were still working to cover life-preserving services.
The striking members would have a presence near Tauranga Hospital and were planning to walk down Cameron Rd this morning from about 8.30am.
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