"Mako sharks this size are not uncommon off Hawke's Bay, as evidenced by the numbers of large makos landed in game fishing tournaments ... [but] strandings such as this are rare."
Despite its size and the species' "aggressive nature", there was no need for local swimmers to be fearful, he said.
"Makos feed primarily on pelagic fishes such as tunas and marlin, other pelagic sharks and squids. However, they can be extremely aggressive and large makos have been known to make unprovoked attacks on boats.
"Makos are famous for attacking boats when they've been hooked."
He estimated the shark was probably a female, aged between 18 and 20 years old.
The marine scientist, who swam with makos off Napier during his research here, said encounters with humans were rare because of their preference for deep, offshore waters.
"Their aggressive nature always meant you had to continually monitor your behaviour towards them."
Mr Wiig said he doubted the incident would deter Blackhead residents from entering the water.
"There are a lot of divers on this beach but no, this is a once in a lifetime thing."