A call for caution in the Chatham Islands -- in light of a fatal shark attack on a young commercial diver

A 24-year-old man was injured around midday yesterday, and later died at the local medical centre.

It's thought a great white is the culprit -- with the area a hotspot for them at this time of year.

Auckland Museum Marine Biology Curator, Clinton Duffy, says the sharks can reach more than seven-metres in length.

He says they are a formidable predator, and one of the few sharks big enough to take on a human.