© RNZ / Diego OpatowskiA cuviers beaked whale washed up on the beach south of Titahi Bay near Wellington this morning.

Onlookers have flocked to a beach at Titahi Bay, north of Wellington, to see a dead 6m-long whale which washed up overnight.

The whale, believed to be a cuvier's beaked whale, was first spotted about 8am today.

Department of Conservation's (DOC) marine species team manager Ian Angus said the whale was a deep-water species and appeared to be mature.

He said although cuvier's beaked whales had stranded on New Zealand shores before, it was not common.

"I can't see any obvious damage to it or injury, so I presume it died at sea and a combination of wave and wind has brought to Titahi Bay," he said.

DOC has put up a cordon around the whale to discourage people from touching it; one person nearly stood on it, a DOC staff member said.

Ngati Toa communications manager Jennie Smeaton said a karakia was performed on the whale this morning before people started to arrive.

"It was quite hard to contain the people that were coming. Everyone wanted to have a look," she said.

"It was just that members of the DOC team were also concerned about how long the whale had been dead for and the decomposition of it."

DOC was working with local iwi and council to remove the whale before it becomes a public health hazard, Mr Angus said.

"We'll look at the logistic and sometime during low tide later this afternoon we'll make a decision about the disposal of the whale.

"The important thing is to take into account local iwi's wishes and working with iwi on the burial," he said.