Several great white sharks have been seen in the Waihi area before a fatal attack, including one which put its nose on the back of a fishing family's boat.

A woman believed to be in her 20s died on yesterday after a suspected shark attack off Waihi Beach.

There have been four reported sightings of great whites in the Bowentown channel before Christmas, says Department of Conservation shark expert Clinton Duffy.

But it would be difficult to say which species of shark is responsible for the attack, as several are around the Bay of Plenty during summer - including bronze whalers, mako and hammerheads.

The Molisi family from Tauranga had a close encounter with a great white before Christmas, after launching from Bowentown.

The Molisis often fish around Waihi and, on December 19, came across a shark when fishing in ANZAC Bay.

'It swam behind the boat putting its nose on the back of the boat. It was there for a couple of minutes,” says Maria Molisi.

It is the first time the family had experienced anything like it.

'It was exciting, our kids on the boat were trying to lean over the side, so we had to pull them back a bit.

'It was a shock to see one, we didn't expect to ... And seeing the fin out of the water.”

Molisi says the experience has made her husband a bit more cautious about swimming in deep water.

The family was at the beach when the fatal shark attack happened, but was separated from the scene by sand dunes.

Jo Lines-MacKenzie/Stuff.