Africa's most fascinating rivers showing their unique habitats - above and below the water's surface. Rivers are the lifeline of Africa's great wilderness areas. Through the millennia these places of water have helped shape the evolution of species and entire ecosystems. Yet few flow all year round. In this series we choose 13 dramatically different rivers, each with its own unique characteristics, from the powerful Zambezi to the dry Hoanib River - a river that flows for only a few days a year. Each river flows through a different part of Africa, bringing life to dry deserts, flooding great plains and supplying constant water to tropical forests and bushveld. The rivers have a formative influence on the lives of animals and plants that live along its banks and in its waters. We show underwater sequences of creatures that live and hunt in the rivers of Africa. We will follow the hunting techniques of the tiger fish and the protective instincts of mouth-brooding tilapia. Along the water's edge, we will show the nest making rituals of migrant birds, the fishing methods of shoebills and the life cycles of frogs. Backed by the character of each river, we tell the story of the different animals - mammals, reptiles, birds, amphibians, fish and invertebrates - who depend on its waters for life. Each episode will provide a rich cross section of the flourishing wildlife diversity that inhabits Africa's waterways.
Gift of the Rains - Episode 1: Hoanib - The Hidden river.
In the desert wilderness of Namibia, on southern Africa's western coast, there is an unusual river that lies hidden beneath the scorching sand for most of the year. It is an ephemeral river - a river that flows above ground for only a few days a year. The water that feeds the Hoanib River collects in the mountains of north-western Namibia. Its course cuts through the desert, travelling mainly underground all the way to the Atlantic Ocean where its waters fan out into a lagoon that is separated from the sea by a pebbled dune. Only when exceptional rains fall over the mountains does the water in the lagoon rise enough to break through to the sea. The animals that live here have learnt to adapt to the harshness of the desert where both food and water is scarce. But, although the river flows underground, it provides enough moisture close to the surface to support a thin oasis of trees and bushes. Giraffes and elephants reach in the trees to pick leaves and pods off the ana tree - a remarkable tree that produces nutrient-rich pods when all other desert plants lie dormant. Small creatures such as gerbils hide in the small bushes that line the river's course. Along the course, underlying bedrock forces the river to the surface in the form of natural springs where animals, such as the terrapin, otherwise not associated with the desert, can survive on the thin trickle of water. Elephant herds migrate along the river valley in constant search for fresh vegetation and water. \nWhen the rains fall over the mountains the gush of water replenishes the Hoanib. The abundance of water flowing over the desert is short-lived, in just a few days it all seeps into the ground and the plants and animals of the desert have to rely once more on their skills to survive in one of the harshest environments on Earth.
Gift of the Rains - Episode 2:Zambezi - The Mighty river.
Africa's landscape is sculpted by some formidable rivers and the Zambezi is one of the continent\'s mightiest. It is a river to which man has attributed a spirit of its own. It's course is marked by the Victoria Falls - one of the natural wonders of the world - as well as two dams, of which Kariba is as large as the country of Whales. But the heart of this formidable river lies in the Zambezi Valley, a wild area protected from civilisation by tsetse fly infestation and the creation of two national parks that stretch into two countries - Zimbabwe to the south and Zambia to the north. Through rain and drought, from summer to winter the animals of the Zambezi Valley find refuge along this section of the river as well as a guaranteed source of food and water. But these waters harbour dangers too. Crocodiles are always on the alert for prey and beneath the surface tigerfish, like the crocodiles, are accomplished hunters. When the summer rains come to the valley, and fill the pools of the land buffalos and elephants leave the river, but some animals, like the resident birds and spotted-neck otters, will always rely on this river - one of Africa's mightiest - the Zambezi.
Gift of the Rains - Episode 3: Luangwa - River of Extremes.
Hidden between the mountains of Africa's Rift Valley flows a majestic river that brings an abundant surge of water to the Luangwa Valley. But this abundance does not last throughout the year, changing dramatically between summer and winter from a full-flowing river to a muddy trickling stream.\nDuring this dry period life for the animals that live along this river becomes a constant struggle. Hippos that need to submerge in water deep enough to cover their bodies are pushed closer and closer together until violent fights break out, sometimes ending in the death of the weaker contestant. Animals, such as the elephants and the endemic Cookson's wildebeest are drawn to river from the surrounding valley, to find water and food. \nIn the drying pools that line the shrinking river course, buffalos find a deadly trap. But for the lions of the Luangwa this is a time of plenty taking advantage of the trapped animals. The drying pools become a death trap to fish as well. Their struggles in the muddy water attracts the larger birds such as pelicans, fish eagles and marabou storks who find the catfish an easily caught prey. Fights between the bird species ensue during the fishing party.\nAfter six months of no rain life for the animals becomes extremely desperate. Just as there seems to be no hope of survival, the clouds gather over the mountains and rain brings relief to the Luangwa Valley and its inhabitants. Almost overnight the river fills to its full majesty and all is well in this forgotten valley hidden between the mountains of Africa's Rift Valley.
Gift of the Rains - Episode 4: Okavango - The Miracle River.
One of Africa's most remarkable rivers spreads its waters over the desolate plains of the Kalahari Desert, forming the largest inland delta on Earth, the Okavango. Fed by the summer rains that fall over southern Angola, the Okavango River flows into the heart of the desert in Botswana. The water flows slowly over the flat expanse of the Kalahari and fans out into shallow lagoons and wide floodplains.\nWater plants germinate in the newly flooded lagoons and provide food for many water birds. At this time, several bird species such as marabou storks and herons breed and raise their young, living side by side in heronries.\nAs the floodwaters recede, African skimmers also breed, hatch and fledge their brood. In the shrinking channels of the delta, thousands of fish are chased out of hiding by barbel weaving among the reeds. The fish are also caught by egrets, storks and herons from above. Another predator that benefits from the barbel run is the Cape clawless otter, which preys on the barbel themselves.\nAs the water recedes further, the desert reclaims its land, except for a few permanent streams and lagoons. Eventually, the summer rains replenish the Okavango, and the delta once again becomes a bountiful oasis.
Gift of the Rains - Episode 5: Mara - River of Strife.
The seasons bring life to the valleys forged by the African rivers, but they also play a part in nature's tragedies. For most of the year, the Mara River flows peacefully through the wide grassplains of Southern Kenya, but during the dry months it displays the ultimate life-and-death struggle: the crossing of hundreds and thousands of wildebeests.\nThe great herds migrate from the south to their winter grazing grounds on the western bank of the river. The zebras are the first to brave the crossing of the Mara, despite the danger from the crocodiles. After a meagre diet of barbel, the crocodiles feast.\nThen the huge wildebeest herds arrive at the Mara's banks. Driven by instinct, they too forge the crocodile-infested river. After a gruelling river crossing, the wildebeests finally reach their winter pastures. They remain here until the summer rains prompt them to return to the Serengeti, but this involves crossing the Mara once more.
Gift of the Rains - Episode 6: Victoria Nile - River of Beginnings.
The quest to find the source of the Nile built and shattered explorers' dreams for centuries, until it was eventually discovered that the river's birthplace is Lake Victoria. The first part of the great river is called the Victoria Nile, it connects Lake Victoria to Lake Albert through a series of rapids and the powerful Murchison Falls.\nNile crocodiles have been using the banks of the river as nesting sites for centuries, showing a nurturing side unique in the reptile world. Dikkops nest near the crocodiles, for protection from scavengers such as monitors. The endemic shoebills hunt along the marshy edges of islands in the wide river. A herd of elephants come to these reed-covered islands to feed, where there is easily accessible food for a calf with a mutilated trunk. The islands, and the banks of the river, form the traditional mating ground for Ugandan cobs. The Victoria Nile is also a convenient stopover for migrating Abdim storks.\nIn this part of Equatorial Africa, seasons do not affect the flow of the river, which continuously provides a stable home for its inhabitants.
Gift of the Rains - Episode 7: Shire - River of Fertility.
The Shire River is one of the few African rivers that flows steadily and peacefully throughout the year. It flows serenely through southern Malawi, fed by the abundant waters of Lake Malawi. The lake contains more fish species than any other lake in the world, including at least 600 types of cichlids, small colourful fish that protect their eggs and fry in the mother's mouth. When the Shire River leaves Lake Malawi, the Great Rift Valley is no longer a deep gorge, and the river flows placidly in a wide valley. Winter is usually a time of drought in Africa, but the Shire is fed by the constant supply of water from the Lake, offering a constant abundance to the birds and animals that inhabit its banks. Hippos, crocodiles and waterbuck adorn the banks, and elephants migrate to the river during the dry season. All year round, this is home to one of the biggest fish eagle populations in Africa. The Shire is a river of plenty and fertility. It is a breeding haven for many creatures, from hippos to water monitors to birds such as bee-eaters and whitebreasted cormorants.
Gift of the Rains - Episode 8: Sand - River of Riches.
The Sand River is shorter and smaller than many of Africa's rivers, but it has great importance because it supports such an abundance of wildlife. The river is born in the Drakensberg Mountains in South Africa, flowing for 80km until it joins the Sabie River.\nIn winter the river runs at its lowest, exposing the sandbanks that give it its name. At this time, the Sand is the only source of water for the buffalos, elephants and other animals of the area. The lions also stay close to the river, knowing that their prey, such as buffalo, must pass regularly through their territory. To avoid competition with these powerful nocturnal predators, the cheetah hunts by day.\nWhen the summer rains arrive, the river swells and floods, the only time of year when the elephants can submerge their whole bodies. Soon the Sand settles down to a steady rich flow, which continues through the summer. This is the mating season for the mouth-brooding tilapia and the foam nest frogs, each with its specialised breeding arrangement. \nThrough summer and winter, the Sand River enriches the diversity of creatures that make their home in its waters and along its banks.
Gift of the Rains - Episode 9:Limpopo - River of Giants.
The Limpopo River in Southern Africa is a giant, not only in its size, but also in the wealth of animal life it supports.\nIn the dry season, the river is the only source of water for many animals, from the giants such as elephants to the smaller creatures. Other giants of the Limpopo include predators such as the python, the largest snake in Southern Africa, and the leopard, which is both the largest spotted cat and the largest solitary hunter. The river is a lure for their prey, particularly in winter.\nAt this time of year, the slow-moving river becomes an ideal habitat for algae, which is enjoyed by the tilapia and other fish.\nWhen the rains come in summer, the Limpopo swells to giant proportions, saturating its floodplain. Now there is water available further away from the river, and the animals are able to disperse to the valley.
Gift of the Rains - Episode 10:Rufiji - The Perennial River.
The Rufiji River flows through Tanzania in East Africa, through the vast Selous Game Reserve - the largest reserve in the whole of Africa. It is home to a variety of creatures such as the unique Selous wildebeest, and is a precious haven for endangered animals such as elephants and wild dogs. The river flows all year round, always faithfully providing an ample supply of water. However, food is scarce for the herbivores during the long dry season, and hippos are forced to leave the water for long periods to graze enough of the sparse vegetation on the banks. The animals that depend on the generous river for their food, such as water mongooses, waterbirds and crocodiles, are much less affected by the drought. The predators are also very well fed, and winter is the wild dogs' peak breeding season, when hunting is easiest. There are two rainy seasons in Tanzania. The first to arrive are the short rains, which only last for a few weeks and do not bring much relief to the vegetation, as most of the water runs off without penetrating the soil properly. The long rains finally come three months later. The Rufiji fills and the valley flourishes and blooms once more.
Gift of the Rains - Episode 11: Olifants - River of Treasures.
At the southern tip of Africa, the Olifants River flows through and nourishes the unique Cape Floral Kingdom. Despite being the smallest of the world's six plant kingdoms, it is the richest and most spectacular, containing 3% of all the plant species found in the whole world.\nBaboons and grey rheboks feed on the plentiful 'fynbos' or 'fine bush' plants in the lush wetlands surrounding the river. Malachite sunbirds and endemic Cape sugarbirds cross-pollinate protea flowers as they feed on the sweet nectar.\nWhen the spring comes after the winter rainfall, the Cape floral kingdom comes to life in a magnificent display of colour. Insects flourish, breed and feed on the abundant food, while ants disperse the seeds of many plants.\nMany rare fish that occur nowhere else in the world find a safe home in the Olifants River's clear unpolluted waters. These endemic species include Clanwilliam redfins, sawfins and Clanwilliam yellowfish.\nHalfway down its course, the river fills the Clanwilliam Dam. From the dam to the sea, the Olifants is bordered with man-planted alien vegetation and cultivated lands. Nonetheless, the mouth of the river remains beautifully pristine and true to nature, attracting a rich variety of waterbirds such as common terns, kelp gulls and pelicans.
Gift of the Rains - Episode 12: Pongola - The Generous River.
When in flood, the Pongola River creates a whole new wild world of quiet backwaters, hidden animals and ancient rituals. The river is born in the Drakensburg, and flows through one of the most remote parts of South Africa - Maputaland. With the summer rains, the Pongola floods, filling its pans which are home to hippos, great white egrets and goliath herons. Cane rats live in the lush vegetation along the banks, unseen by the warthogs and other creatures who also inhabit the area. Terrapins come to the muddy banks to lay their eggs. Migrating white pelicans visit when the pans are at their lowest and the fish are concentrated into schools. Crocodiles winter in the pans, but return to the river itself year after year to breed. Openbilled storks hunt in the quiet shallows of the river. In order to reach their spawning grounds, redbreasted tilapia battle across a man-made causeway in the feeder channel, making their way between crocodiles, herons and other predators. The Pongola River and its pans are a valuable habitat to many species dependent on this generous river.
 |
Subscribe to this comment's feed
