Defassa Waterbuck are large and handsome antelopes that are quite common along the Narus River in Kidepo National Park. They require fairly open grassland and they don’t stray far from water.
Any number of subspecies have been described but they fall into two groups. The more easterly group, Common Waterbuck, was the first described and given the scientific name Kobus ellipsiprymnus. Kobus is an African name given a faux Latin ending. Ellipsiprymnus is from Greek – ellipsi meaning ring and primnos meaning hind part. It was so named because of the white target on the animal’s rump.
The more westerly group was described as a separate species, Defassa Waterbuck, but where the ranges meet they hybridise readily and the two groups are now lumped in the one species. There is no white ring on the rear end of a Defassa Waterbuck. So it now has a scientific name celebrating a feature that it doesn’t have.
Only the males have horns and these are used in competition for access to females.
They are said to taste terrible which is quite an advantage when it comes to living with lions and human beings.
The camp at Kidepo National Park is remarkably relaxed. There is an armed guard at the gate on the road. He or she checks your ID then raises the boom gate … but there’s no fence. You are advised to take your torch out with you at night and to look around for wildlife before stepping away from your door.
Warthogs and jackals wander around the bandas. There are Waterbucks on the soccer pitch. One morning I was obliged to take an alternative route to breakfast because there was a buffalo between me and the restaurant. The following morning a lion could be heard roaring just outside the camp.
The warthogs and jackals are quite habituated to human presence, the jackal is the more cautious as well as the more handsome of the two species.
The Kingdon Pocket Guide to African Mammals offers three jackals to choose from – Black-backed, Side-striped and Common. On this basis this guy is a Common Jackal because of the coloration and the black tip to the tail …
but other authorities treat the group a little differently. The name Golden Jackal is preferred to Common and the subspecies that occurs in Africa has recently be proposed as a full species with the name African Golden Wolf.
It can be seen from this phylogenetic tree (other researchers have published different trees} that the Golden Jackal is not closely related to the other two jackals nor is it an immediate neighbour to the African Golden Wolf. The physical similarity between the (Eurasian) Golden Jackal and African Golden Wolf may be explained by parallel evolution.
Just to complicate matters all the wolf-like canids have similar morphology and 78 chromosomes. They can and do hybridise with other canid species in the contact zones.
Specifically, we find gene flow between the ancestors of the dhole and African hunting dog and admixture between the gray wolf, coyote (Canis latrans), golden jackal, and African golden wolf. Additionally, we report gene flow from gray and Ethiopian wolves to the African golden wolf, suggesting that the African golden wolf originated through hybridization between these species. Gopalakrishnan et al.
You’ll notice that I haven’t put a final diagnosis in the Jackal captions.
On this visit to the Budongo forest our attentions were focused on the bird banding team which since our last visit had matured into a very efficient operation. We hadn’t set aside any time to specifically follow monkeys or the star attraction, chimpanzees. But this is Budongo, any spare half hour could be put to excellent use.
The key to photographing the monkeys is simply to take your time. Approach quietly, when they start to examine their escape route just settle. After a while they resume feeding or grooming and soon you’re just part of the background.
They may walk right by you.
In that instance I was sitting on the ground and found myself shooting up at mum and her youngster. An older youngster got left behind and came running to catch up …
The next character and I conducted a lengthy study of each other.
The Colobus and Red-tailed Monkeys are a tougher prospect because they spend so much of their time high in the trees.
The ice ages were a series of major glaciations with intervening interglacials. This process has been playing out over about two and a half million years. The epoch over which this all occurred is the Pleistocene.
The last glaciation finished about 11,500 years ago. Our present epoch has been given a new name, the Holocene, which implies that this is something different not just another interglacial. We shall see.
Prior to the Pleistocene the world was a warmer place. This was the Pliocene an epoch that spanned about 9 million years. In mid-Pliocene temperatures were 2 or 3°C warmer than present , sea levels were about 25 metres higher. Continents were wandering very slowly. In the late Pliocene South America collided with North America, bringing about an interchange of flora and fauna and also bringing about a change in ocean currents and climate.
A collection of cold adapted mammals emerged from a variety of families. Where did they come from? Ice is the unifier of the Arctic, in its absence sea levels are higher and land mammals don’t enjoy the ability to wander from one side to the other. That makes it a poor candidate . The Antarctic continent is cut off by the Southern Ocean making it an even worse candidate.
By contrast the Tibetan Plateau even though close to the equator is at sufficient altitude to rival the true poles for cold weather. It was called the third pole by Marcel Kurz, the great Swiss geographer, mountaineer and explorer. It is well-connected to surrounding land masses meaning that a good variety of mammalian families were represented there during the good times of the Pliocene. As the cold times came on the Tibetan fauna adapted. During the height of the glaciations they could radiate out far to the north.
The Out of Tibet Hypothesis suggests that the Mammoth, Woolly Rhinoceros, the Three-toed Horse, Sabre-toothed Cat and other cold adapted megafauna originated in the Himalayan mountains. For example the Arctic Musk Ox and the Himalayan Takin are fairly closely related being the only extant members of the tribe Ovibovini.
Since most of the cold adapted megafauna shuffled off this mortal coil in the last 10,000 years you might be wondering where this is going. There are Musk Ox on Svalbard but I wasn’t lucky enough to see or photograph them but I did catch up with another creature that provides a strong link with Tibet …
At under 5kg they don’t qualify as megafauna but according to Xiaoming Wang et al. the Arctic Fox is descended from the Early Pliocene (3.60–5.08 Myr ago) high altitude fox, Vulpes qiuzhudingi which they have recently discovered, and which they consider support for the Out of Tibet Hypothesis. The following figure is shamelessly stolen from their article.
The Arctic Fox has a fairly short life, typically 3 or 4 years, 10 or so if they are lucky. When food is abundant they can have large litters (as many as 25 – the largest litter size among the Carnivora) although 5 or 6 is more usual. This is a very different life strategy than the Polar Bear.
As can be seen in the photo above there are two colour morphs. This is genetically determined. On Svalbard 85 – 98% of the population is the white form. This despite the fact that the gene for the blue form is dominant. There is clearly some selection pressure against the blue form. This was certainly true in the fur hunting days when pelts of the blue form were worth considerably more.
If you do a Google search for Arctic Fox you will be overwhelmed with links for a semi-permanent, vegan haircolouring. An odd choice of name for a vegan product – the Arctic Fox is a ferocious little predator. Lemmings are high on the menu where they occur (no Lemmings on Svalbard) and birds elsewhere. They take carrion, seal pups and some plant food . When you see a Polar Bear there is often a fox not far away hoping to steal a few mouthfuls. Some food is cached for winter consumption.
Arctic Foxes are susceptible to rabies and toxoplasmosis. They are the final host of the tape worm Echinococcus multilocularis, a parasite that can be fatal in humans.The Norwegian Polar Institute recommends wearing gloves if you intend to handle fox faeces.
Our intrepid leader, Pete Oxford, had with him an underwater camera, lighting and the most heavy-duty waders I have ever seen. No wonder his luggage was slow to arrive. His hope was that he would be able to get close to a Walrus either under water or half above and half below. Given the puncture wounds we had already seen this was to be a hazardous venture.
But you don’t make the cover of National Geographic without taking a risk.
But it was the turbidity that got him not the tusks.
The visibility under water was poor and this in the period when the sun doesn’t set. There can’t be much to see when it doesn’t rise. This is likely the reason that the Walrus has such impressive vibrissae …
Likewise the Bearded Seal
As well as assisting in finding food it has been suggested that the whiskers help to find breathing holes.
Apart from the Walrus, sole representative of the Odobenidae, the remaining seals in the Arctic are all members of the Phocidae, True Seals. There are no eared seals above the Arctic circle. The Phocids are the master divers but the waters we were in are fairly shallow. The records all go to the Elephant Seals in the southern hemisphere.
Among their adaptations for diving seals have nostrils that are closed at rest. It takes a muscular effort to open them to breathe. It may not seem much but it means that a little less oxygen is required when oxygen is scarce and energy is needed to pursue food. This can be seen well in the Harbour Seal photos below.
Even without a heart-shaped nose they look ineffably cute, you can understand why they have their admirers …