Nature's Greatest Moments

- Season 1

(1999)

The great white shark has long been the centre of media hype, but is it really the vicious killer it is made out to be? We take a look at the hunting strategies of this incredible shark and find that it actually is an intelligent, calculative and cunning predator.

The most endearing mammals in the world are the dolphins. We follow a family of bottlenose dolphins as they move in their home waters and over a reef of the southern Indian Ocean. We watch them play, fight, love and 'cry'.

The sand tiger, or ragged tooth shark, is a sinister-looking humped back creature with a mouthful of wicked teeth - the embodiment of nightmares. Yet it is hardly the vicious killer of our imagination and on a reef off the coast of South Africa divers have grown to love this ugly shark. In this episode we follow the ragged tooth shark from its summer habitat in the Cape to its winter mating waters in KwaZulu-Natal. (Diver/shark interaction to show how close divers actually get to the sharks)

Off the coast of Mozambique there is a small reef which is the castle of an imposing king - Bert the Bass. He is a huge potato bass. Like all basses he has an unusual life history - he began his life as a female and changed sex when he grew into an adult. He now rules over his harem of females as well as this small patch of reef.

Each year, off the coast of Southern Africa, millions upon millions of sardines school together and move en-masse up the eastern coast. They are followed by many marine predators including sharks and bottlenose dolphins. We explore the dynamics of the sardine run and the hunting strategies of some of the hunters. (I think we can manage a short 5 minuter on this without using Greatest Shoal footage and using mainly what is already in Blue Reef)

Some of the largest fish in the sea feed on the tiniest of marine organisms. Manta rays and whale sharks feed by filtering the water and extracting the tiny creatures that form plankton. But they are able to do this by swimming forward in the water with mouth agape, but there are creatures such as corals and sponges that are attached to the reef and need to reach into the water with tiny tentacles to catch the passing plankton.

Beneath the tropical waters of our oceans lies one of the most intricate worlds ever evolved - tropical reefs. Although they occupy only one tenth of the earth's surface they achieve the highest productivity off all marine ecosystems, second only to the tropical rain-forests in complexity and richness. And they are built by the most delicate of creatures no bigger than a baby's finger.

The Maldive Islands form a beautiful string of coral reefs, popular with divers all over the world. A disused ship forms an artificial reef and is home to the friendliest stingrays you're ever likely to meet. Tempted by the fish the divers bring the stingrays sometimes get very cheeky and try to touch or catch the diver's equipment. Their long whip-like tail, with it's poisonous spine, is designed to fend off potential predators but they do not need to worry about using it here.

The proverbial saying is that there's safety in numbers and many fish species have found this to be true. Small fish huddle together and move as one through the water hoping to appear larger to a passing predator, while pelagic predators such as barracuda move in vast schools to hunt. We explore the different schooling strategies of both reef fish and deep-water inhabitants.

Sharks are some of the most fascinating creatures to roam the ocean. There are many species of different shapes and sizes each adapted to its own way of life. Some sharks, like the silvertip and blacktip, prefer to hunt in the open ocean. Grey reef sharks hunt at the edges of the reef. Leopard sharks have no teeth, but have developed a hard plate instead to crush mollusc shells. This episodes will show that there is a lot more to sharks than is commonly know.

Unbelievably rays are related to sharks. They both have a skeleton made of cartilage, but as they evolved they developed flat disk-like bodies that 'fly' through the water rather than swim. Many rays have learnt to bury themselves in the sand for protection and to ambush their prey. Most of them have mouths on the underside of their flat bodies to dig into the sand and catch buried prey. Others fly perpetually through the water in search of food. We compare the different species and show the rarest and a newly discovered one.