Sharks

Great White Shark – Carcharodon carcharias

Bull Shark - photographed by underwater australasia member David BaxterOther common names for this shark include White Shark, Great White, White Pointer and White Death. An amazing powerful shark no doubt with refined senses to detect and catch its prey. The main diet of the Great White Shark consists of fish and smaller sharks. Only the larger individuals will have a go at seals and dolphins.

The Great White Shark has a solid body, pointed nose and crescent-shaped tails. Its colour is slate grey with a bronze sheen on the top and white below. The eyes are black and round and the teeth are visible as the mouth is always slightly opened.

In Australia they are found from North-West Cape in Western Australia to the south of Queensland, but they are mainly seen off the coast of South Australia.

The maximum length of this shark is not really known, but the largest ever caught measured 6 meters. Trust me, this is an impressive shark at any size.

Considered dangerous to human.

*Image by underwater australasia member Daniel Norwood

Bull Shark – Carcharhinus leucas

Bull Shark - photographed by underwater australasia member David BaxterA resident Bull Shark can regularly be seen at the Yongala Wreck, off Townsville and doesn’t seem to pose a danger to the divers visiting this wreck. They are also common at the shark feeding at Beqa Lagoon, Fiji with plenty of people being very excited about the opportunity to be in the water with them.

Bull Sharks are a more tropical shark and live all around northern Australia from Perth to Sydney. They prefer murky waters near the coast. Bull Sharks are also called River Shark or Freshwater Whaler due to their ability to live for extended time, and even breed, in fresh water and have been found kilometres upstream of large rivers.

Considered dangerous to human, especially since they are more likely to visit places where people swim.

*Image by underwater australasia member David Baxter

Tiger Shark – Galeocerdo cuvier

Tiger Shark - photographed by underwater australasia member Iwona KrekoraTiger Sharks have a diverse diet and are more opportunistic feeders than the other large sharks and bizarre items have shown up in its stomach contents. These sharks will go for both live prey and carrion. However, sometimes they go for a more specific prey and timely show up at areas near rookeries where young seabird learn to fly, at turtle nesting areas etc and wait for dinner to drop in.

Although considered dangerous to humans, when attending the shark feed at Beqa Lagoon, Fiji they are a regular visitor and people are rapt about the opportunity to get up close with them under “controlled” circumstances.

Tiger Sharks are a large species with a blunt, almost square, head and large black eyes set forward on the snout. Its back is grey with darker tiger-like grey stripes (hence the name), which sometimes fade completely when the animal gets older.

The Tiger Shark is common in the tropics and also occurs in temperate waters off the New South Wales and West Australia coast during summer. They hunt in harbours and around shallow reefs and are therefore more likely to encounter humans more often than the other species of dangerous sharks.

Tiger Sharks can reach a maximum length of 6 meters, but are usually between 3 – 5 meters.

Considered dangerous to humans.

*Image by underwater australasia member Iwona Krekora

Scalloped hammerhead – Sphyrna lewini

Scalloped Hammerhead Shark - photographed by underwater australasia member Michael RoetThe Scalloped Hammerhead Shark usually eats fish and squid, which they hunt for at night in the deeper waters.

Their oddly-shaped head is thought to be more efficient at detecting electrical variations and helps the shark at swiftly turning when chasing their speedy prey.

This rather shy shark can sometimes be found in large schools.

Hammerhead Sharks are easily identified due to the distinct shape of their head. The Scalloped Hammerhead has several indents at the front of its snout. This shark has a grey-brown back and a lighter underside.

Scalloped Hammerhead sharks live all around northern Australia from Perth to Sydney. This shark species can reach a maximum length of 3.5 meters.

*Image by underwater australasia member Michael Roet

Grey Nurse Shark – Carcharias taurus

Grey Nurse Shark - photographed by underwater australasia member Peter HitchinsThe Grey Nurse Shark have longish fork-like teeth that can easily been seen even when their mouth is closed, making them look much more scary than they really are. These teeth are being used to catch their prey such as fish and small sharks and rays.

Known also as the Sandtiger Shark this species was long thought to be a ferocious man-eater. Many of these sharks were killed during the 1950 – 60s until it was realised that Grey Nurse Sharks very rarely attack humans and only when they are cornered or when people carry dead fish around their waist.

Grey Nurse Sharks have a bronze coloured back, a pale belly and a pointy snout with their teeth protruding. Some have darker spots on their sides, which always remind me of freckles, although I doubt they do a lot of sunbaking.

In Australia they can be found from Southern Queensland down to south New South Wales on the east coast and in the South West of Western Australia. They migrate to the relative warmer waters in winter.

The Grey Nurse Shark is considered critically endangered on the east coast of Australia and is a protected species.

Grey Nurse Sharks can grow to 3.2 meters.

*Image by underwater australasia member Peter Hutchins

Spotted Wobbegong – Orectolobus maculatus

Spotted Wobbegong - photographed by underwater australasia member Michael GallagherWobbegong Sharks are pretty common in Australia and there are 4 different species that can be found here: Ornate Wobbegong, Spotted Wobbegong, Tasselled Wobbegong and the Dwarf Ornate Wobbegong.

The word ‘Wobbegong’ believed to come from an Australian Aboriginal language, meaning ‘shaggy beard’ referring to the branched lobes around the mouth, according to Wikipedia.

Their mottled, camouflaged appearance, flattened head, frilly appendages at their mouth and the fact they lie motionless underneath rocks earned them the alternative name of carpet shark. Although the individual species are easily confused you would not mistake them for any other shark due to their unique appearance.

The Spotted Wobbegong mainly feeds at night and feeds on fishes, crayfish, crabs and octopuses.

This Wobbegong is the largest species of the Australian Wobbegongs and with its maximum length of about 3 meters it is an impressive sight to see a large one swim past or even towards you! Spotted Wobbegongs are mottled brown and yellow with distinct circles of small white spots.

The Spotted Wobbegong occurs along the southern coastline of Australia from southern Queensland to south-western Western Australia and is probably unique to Australia (endemic).

All wobbegong sharks can look ridiculously docile, but do not try to pick them up oklpi09or pull their tail! This shark is able to turn 180 degrees in a flash even if you manage to hold on to their tail. Their bite can be serious as they have plenty of sharp teeth to hold on with.

*Image by underwater australasia member Michael Gallagher

Whale Shark – Rhincodon typus

Whale Shark - photographed by underwater australasia member Daniel NorwoodThe largest fish in the ocean hunts by opening its large mouth and swallowing everything that gets stuck inside. Plenty of plankton gets caught in sieve-like gill rakers, but schools of fish can also get stuck in its mouth and even the odd small tuna or squid make their way inside.

Whale Sharks are very easily recognised due to the sheer size. Its back and sides are covered by a checker-board pattern of dots and lines. The head is blunt.

The pattern on a Whale Shark is unique to the animal and researchers are using those patterns for identification and tracking of individual Whale Sharks.

Whale Sharks are found in tropical seas all around the world and may be seen all around northern Australia from Perth to Bass Strait. Generally people encounter them when they are swimming and/or feeding near the water’s surface.

Every year from March until the beginning of July Whale Sharks migrate past Exmouth in Western Australia and people have the opportunity to snorkel along side. Strict rules apply as to not harass the animals, but also to avoid people getting hurt by this gentle giant.

Most Whale Sharks are 4 – 12 meters long, but the largest Whaleshark that has been caught was documented as being 12.6 meters long and have a girth of 7 meters!

*Image by underwater australasia member Daniel Norwood

Leopard Shark – Stegostoma fasciatum

Leopard Shark - photographed by underwater australasia member Sami VaryrynenThe Leopard Shark is another shark species you do no have to be afraid of. They can often be found resting on a sandy patch and can easily be approached.

These sharks feed mainly on shellfish as well as shrimp and small fishes.

The adult animals feature leopard-like spots on top of their body and the top of its tailfin has the same length as its body. The juvenile ones feature a striped pattern hence the alternate name of Zebra Shark. The Leopard Shark has a blunt head and very small eyes.

This shark prefers warmer waters of 22°C and up and normally can be seen in the warmer waters on shallow reefs from Carnarvon, Western Australia to Sydney.

The Leopard Sharks can reach a maximum size of 2.5 meters.

*Image by underwater australasia member Sami Vayrynen

Grey Reef Shark – Carcharhinus amblyrhynchos

Grey Reef Shark - photographed by underwater australasia member Karl Scaife

The Grey Reef Shark or Grey Whaler Shark has sharply pointed but small teeth. They mainly eat small reef fishes and occasionally squids or crayfish.

When threatened, Grey Reef Sharks will perform a threat display with a hunched back dropped pectoral fins and an exaggerated side-to-side swimming motion- a sure sign to leave it alone. They do give quick warning bites, but are not usually thought to be a threat to humans.

This shark can be recognised by its shark-like appearance and a black edge on the V-shaped tailfin, hence the other common name of Black-vee Whaler. The back is bronze or grey and it has a pale belly.

Grey Reef Sharks are commonly seen on the Great Barrier Reef by divers and snorkelers and can be found on coral reefs, near deeper water in northern Australia from Carnarvon to Bundaberg.

Grey Reefies can theoretically reach a length of 2.5 meters, but most of them are just under 2 meters.

*Image by underwater australasia member Karl Scaife

Whitetip Reef Shark – Triaenodon obesus

Whitetip Reef Shark - photographed by underwater australasia member John FergussonThis common reef shark hunts mainly at night in groups and go for small reef fishes, octopus, cuttlefish, but also crab and lobsters.

Most people are comfortable with seeing a Whitetip Reef Shark on their dive or snorkel trip on a coral reef. These sharks are very slender, torpedo-like and have, as their name implies, white-tipped dorsal fins and tailfin.

Quite often they can be seen lying underneath coral heads or in small caves or swimming near the ocean floor.

Whitetip Reef Sharks are very common on reefs all around northern Australia from West Cape to Gladstone. This fairly small shark can reach a maximum length of 1.7 meters.

*Image by underwater australasia member John Fergusson

Port Jackson Shark – Heterodontus portusjacksoni

Port Jackson Shark - photographed by underwater australasia member Peter PerryPort Jackson Sharks feed at night on a variety of bottom dwelling animals and likes sea urchins and sea stars.

Although this shark would not attack humans care should be taken if you would ever see the need to be handling this shark as a poisonous spine sits just in front of its dorsal fins.

This somewhat odd looking shark is pale-brown with a dark brown harness-shaped pattern on its back. Its head is blunt with bony ridges above the eyes.

Although its name implies it is only found in Sydney’s Harbour the Port Jackson Shark can be found all around southern Australia between Carnarvon, Western Australia and Tweed Heads, New South Wales

Port Jackson Sharks are only small and reach a maximum size of 1.6 meters, but are generally much smaller – around the 1.3 meters.

*Image by underwater australasia member Peter Perry

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