The Bronze Whaler Shark

  The bronze whaler shark is found throughout the Mediterranean Sea and also around Japan, South Africa, Australia and New Zealand. Often going by the name of copper sharks or narrowtooth sharks, bronze whalers can grow up to three metres long. There have been many attempts to enclose bronze whalers in aquariums for public viewing. However, specimens of the genus do not adapt well to captivity and have been known to swim repetitively into the glass walls of their tank, damaging both the glass and themselves. It is also common for them to develop fatal infections from other creatures enclosed alongside them.
  Unlike many sharks, bronze whalers commonly form schools of up to and even above a hundred specimens. It is suspected that the reason for their doing so is that they are often preyed upon by larger sharks such as great white, tiger and bull sharks.

The range of the bronze whaler shark. In dark blue
is the confirmed range, in light blue, the suspected
range.

  Bronze whalers generally feed on fish such as tuna and also prey upon octopi and squid, as the majority of requiem sharks do. In addition, they have been known to consume stingrays and dogfish. Bronze whalers are often observed participating in the Sardine Run around South Africa.
  It is unknown how threatened bronze whaler sharks are by fishing, although they are a popular target of illegal finners. Several conservation projects are now underway in order to protect bronze whalers and other threatened species, despite the fact that bronze whaler numbers are uncertain.
  Attacks on humans by bronze whaler sharks are surprisingly more common than other sharks, although still infrequent. It is, perhaps, to be expected as divers commonly observe these sharks in coastal waters worldwide. In addition, those who dare to observe the Sardine Run from close quarters are often bitten accidentally if a feeding frenzy starts. However, some believe that bronze whalers are also the perpetrators of numerous unprovoked attacks and it is possible that they could soon be amongst the top ten most dangerous sharks to humans, based on recent averages. One explanation for this could be that people have mistaken them for other sharks, as they look very alike several other large species. It is also thought that there may have been several unconfirmed attacks following shipwrecks and aeroplane crashes in the ocean where survivors have been forced to remain in the water for indefinite periods.

A bronze whaler shark swimming nearby a school of
mackerel.

The Sardine Run

  The sardine run is the annual migration of sardines which attracts sharks, dolphins and even whales from all over the place. Nobody knows exactly what causes this mass-migration-massacre, but a popular theory is that yearly changes in water temperature where the sardines normally live on the coast of Mozambique cause the migration to South Africa's warmer waters.
  The sharks whose presence has been recorded at these frantic all-you-can-eat-buffets consist of dusky sharks, bronze whaler sharks, blacktip sharks (not to be confused with blacktip reef sharks), sand tiger sharks, spinner sharks, Zambezi sharks, great white sharks and occasionally thresher sharks. These are accompanied by common and bottlenose dolphins, Cape fur seals, gannets, turns, cormorants, African penguins and whales of all description. The sardines, when faced with such predators, group into tight shoals to form 'bait balls'.
  The following videos have caught the stunning events in perfect light.
http://www.bbc.co.uk/programmes/p004j1rz
https://www.youtube.com/watch?v=0qtvk9znnnY

The sharks snap up the sardines.

A sailfish darts through the bait ball.

The bottlenose dolphins round up the floundering fish from beneath.

The Common Thresher Shark

  The common thresher shark, also known as the whiptail shark, earns its name from its bizarre and yet successful hunting technique: using its abnormally long tail to stun fish. Its tail is equal in length to the rest of the body. These sharks can grow up to six metres long and are very shy of divers.
  Very few get to witness a thresher shark hunting in the wild, as they are reclusive creatures who spend most of their lives in the deepest parts of the sunlight zone and occasionally they may venture into the twilight zone. They generally feed on mackerel, anchovies and herring, but have been recorded as present for the Sardine Run. They also occasionally eat squid and octopi when they are in shallower waters. They can jump to astounding heights from the water in order to catch fish that make a break for it in the air.
  Unlike the majority of sharks, the common thresher posses certain physiological adaptations that allow them to remain warmer than the surrounding seawater, which is a notable advantage when hunting or being hunted.
  Despite their size, common thresher sharks are not a danger to humankind. Their teeth are small and unlikely to be able to puncture the skin of a human. However, it is important to resign to a safe distance when watching a thresher shark hunting, as its tail has also stunned humans in the past, the majority of whom drowned, with a minority being killed instantly due to a severe injury to the neck or scalp.
  Common thresher sharks are in danger of extinction due to gross overfishing. They are primarily one of the foremost species on the 'finners list of soup ingredients' but are also prized by recreational anglers as they are renowned for putting up a large fight when hooked on a line.

The dark blue shows the recorded range of the common thresher shark.
The light blue shows the suspected range of the common thresher shark.

A common thresher shark warily approaching a diver.