It is a stormy day on the Chobe River as we head out in the tenders in search of African wildlife. While birds are sheltering from the rain the hippos are loving the wet weather.
We spot a male hippo grazing on the banks of the river. When he sees us coming closer he trots towards the water and plunges into the river. As we pass only his eyes and nostrils are visible above the water and he watches until we are out of the way. A hippopotamus can stay submerged for up to five minutes and can even sleep in the water. When they are sleeping their bodies automatically bob up to the surface so they can take a breath and then sink back down to the bottom. The hippopotamus gained its name from the Greek word for ‘water horse’ or ‘river horse’ and it must stay moist as its skin will crack if it dries out.
A little further down another young male hippopotamus is resting in the water. As we float past he grunts and opens his jaws in a warning display.
Nearby, a group of hippos has congregated around a marsh area and there appears to have been a disagreement between two of them. These two massive mammals stomp at the ground as they make snorting sounds and yawn at each other, bearing their razor-sharp teeth. Birds fly away as grass and water are thrown into the air. Scars cover the bodies of both hippos, indicating that this is quite a regular occurrence for them.
As we continue we spot a pair of buffalo grazing in a patch of long grass. These great creatures can weigh up to 800 kilograms and both sexes have large, curved horns. The males horns are longer and develop a bigger and stronger ‘boss’ (the centre part), which is used in fights for dominance, during which the male buffalo run and plough into each other with the force of a car hitting a brick wall at 50 kilometres per hour. The boss becomes so strong that it is impossible to penetrate, even with a bullet.
Buffalos live in herds of up to 500 individuals, although some groups of around 2,000 have been recorded. The hierarchy of the herd is such that the stronger, dominant animals walk at the front, in the middle of the herd so that they are protected from threats and can enjoy better grazing. Their social structure and behaviour make them one of the most feared animals in Africa and they are ferocious opponents even to lions, their biggest threat in the wild. It is said that buffalo look at you like you owe them money and with this individual staring right at us, we can see why!
The rain eases and a white-breasted cormorant takes the opportunity to try to dry its wings. These birds are monogamous, colonial nesters that typically live in colonies of under 50 breeding pairs however colonies of over 700 pairs have been recorded. They are usually joined by other breeding birds such as reed cormorants, African darters, African spoonbills, cattle egrets and other herons.
A little further on we spot a spur-winged goose, also drying its wings. This species is a large relative of geese and shelducks but is distinct from both in a number of anatomical features and therefore is treated as its own subspecies. These birds are the largest African waterfowl and, on average, the world’s largest ‘goose’. Spur-winged geese are very fast flyers and can reach top speeds of over 130 kilometres per hour. The birds are highly territorial and have sharp spurs on their wrists, which are typically used to attack other spur-winged geese or other types of waterfowl. Some populations of these birds feed on a poisonous beetle and then sequester the beetle’s poison through their own tissues, making their flesh toxic. The beetles produce the toxin cantharidin, small amounts of which (as little at 10 milligrams) can cause death in humans, and therefore eating the goose can result in death. With its wings now dryer, it flaps a few times and then takes off into the sunset, which is now breaking through the dark clouds.