A Waikato man was mauled by a great white shark after he fell from a kayak on a fishing trip, a coroner's report has revealed.

It is not certain if Maurice Bede Philips, 24, of Ngaruawahia, was attacked by the shark before or after he drowned.

Mr Philips had a large bite on the upper thigh - consistent with one from a 3m great white - that caused huge tissue and blood loss.

Despite the uncertainty, the incident in December 2009 was considered the most recent shark attack in New Zealand waters until this week when a shark bit surfer Peter Garrett, 42, in the leg in Taranaki.

Mr Philips' death had been reported as a drowning, but details of the shark attack are contained in the report from coroner Peter Ryan released to theWeekend Herald.

Mr Philips and a friend were fishing from a kayak near Clark Island when it capsized and they had to swim to shore.

The coroner said a pathologist had identified drowning as the cause of death.

But the large amount of tissue loss from shark bites and the resulting blood loss made it uncertain if Mr Philips died before or after the attack. The evidence was "evenly balanced".

Images of the bite marks on Mr Philips' legs were sent to Department of Conservation shark expert Clinton Duffy, who said a 2.8m-3m great white would have been responsible.

He believed the position of the bite on Mr Philips' upper thigh was consistent with an attack from below, suggesting he could have been swimming on the surface when attacked.