Shark facts: When to get out of the sea and why spearfishing can land you in hot water

Sunday, 31 December 2017

Shark man Clinton Duffy recommends getting out of the water if you see a shark over 1.8 metres.

As summer heats up and the ocean gets warme,r beachgoers are more likely to spot sharks swimming in shallow water.

Shark attacks are rare in New Zealand waters. There have only been nine fatal attacks recorded. But that doesn't mean you won't see one.

Juvenile Hammerhead sharks are common in New Zealand waters.

Marine biologist Clinton Duffy thinks it was likely a bronze whaler that caused swimmers to flee Matarangi Beach in the Coromandel on Saturday evening.

'Bronze whalers are one of the most common species of shark in our waters and they can get up to three metres long,' he said.

* Five-metre great white shark filmed off Australian coast**

Other common shark species include:

1. Juvenile hammer heads

2. Blue sharks which are often seen close to shore. They can grow up to four metres but the ones in New Zealand waters are more likely to be 1.8 - 2.5 metres.

3. Thresher sharks, easily recognised by their very long tails. They can grow up to three metres.

4. School sharks, which often end up in the deep fryer at your local fish and chip shop.

5. Great white sharks swim around the coast of the country. Smaller ones sometimes come into the harbour but they're more likely to be spotted around seal colonies.

In terms of danger, Duffy said the most potentially dangerous shark seen in New Zealand waters is the tiger shark.

'They're big and adapted to feeding on prey larger than themselves, they can be very aggressive but they are rare.'

The bronze whaler is usually a harmless species - unless you are a spearfisherman. They're commonly seen among swimmers and only become aggressive if there's fish blood in the water.

'They probably see the spearfisherman as competition for the fish they've hunting for, they're known to steal fish from fishermen.'

A spearfisherman met his demise in the 1970s when he was killed by a bronze whaler. But Duffy assures that's the only fatal attack from this species documented in New Zealand.

Duffy encourages swimmers to observe the golden rule that any shark over 1.8 metres is considered potentially dangerous.

'If you can't identify it you should get out of the water, quietly and without a fuss.'

He adds if a shark pays more than a passing interest in you, starts speeding up and changing swimming pattern quickly, it's also a sign to get out.