Colours of Wildlife: Bat-Eared Foxes
Created | Updated Jan 10, 2016
Bat-Eared Foxes
Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"
One of South Africa's cutest and fluffiest mammal species is the Bat-Eared Fox, Otocyon megalotis. Its scientific name means 'Ear-dog with huge ears'. Those huge ears are indeed its most distinctive feature, proportionally only slightly smaller than those of the Fennec which occurs much further to the North in the Sahara Desert and Arabia. Bat-eared foxes also live in fairly dry regions, with two large swathes of territory, one in Southern Africa, the other in Northeast Africa, these regions separated by about 1200 km/750 miles in which these foxes are not found.
Not Foxes, Actually
Again we have the theme that has been mentioned so often in these columns. Though called 'foxes', these are not 'real' foxes. In Afrikaans they're called 'bakoorjakkals' or 'big-eared jackal', sometimes 'draaijakkals' or 'turning-jackal', but they are not jackals either. They're a kind of canid, or dog, that is more basal, separated early in time from the other branches of the canid evolutionary tree, before the real foxes and jackals came onto the scene. The Fennec is a real fox, for example. Jackals are the most successful canids in Africa, and are very close relatives of coyotes, wolves and domestic dogs. The Bat-eared Fox is not closely related to these or indeed to any other member of the canid family, forming sort of a group of its own. For dogs, they're on the small side, with reaching an adult bodyweight of 3 to 5 kg/7 to 11 pounds.
Insect-Eating Dogs
Indeed, bat-eared foxes are specialized for an unusual diet – insects! Their favourite food is harvester termites. These are large termites, with dark markings on their bodies, which are unlike other termites in running around above the ground much of the time. Their pigmented bodies make them fairly resistant to sunlight, and they feed by gathering grass by day or by night, nipping bits off and dragging it down into their nests to feed their fungus gardens. Harvester termites occur in many millions on the African savannah, and in some places and times, if you stand still and listen you can actually hear the rustling sounds of them scurrying about and biting off dry grass stalks.
Apart from harvester termites, bat-eared foxes also eat other insects and invertebrates, such as beetles – both adults and grubs – grasshoppers and crickets, moths, centipedes and millipedes, scorpions and camel-spiders (which aren't really spiders – I'll feature them here soon, I hope). Their long, dense fur protects them against bites and stings. They do catch vertebrates but only small ones, mice, mostly, and some lizards and snakes. They also ingest, at certain times, some plant matter. They eat grass, apparently for helping their digestive systems. They've been noted to ingest some dung from large grazers, perhaps inadvertently as they hunt termites. They do actively seek out certain fruits, most specifically the small berries carried by the bushes of the genus Grewia. They only eat these when they are in season; in the autumn, winter and early spring when the bushes are bare, they make do without these fruits.
These doggies use their huge ears for hunting! They can hear insects and other critters scurrying a far way off, or pinpoint their location under the soil. Bat-eared foxes hunt by day or by night. They also have an excellent sense of smell, but their small eyes apparently don't see very well. Their paws have long claws, especially the front ones, for digging. But they don't dig as well as for instance aardvarks do, because they don't need to dig deep to find the harvester termites, these often being easily found in the open. They dig mostly to excavate beetle and other grubs, these rarely being down very deep.
Apart from their huge and very sensitive ears, they have another feature that helps with the insect diet. They have special jaw-opening muscles that, together with the jaw-closing muscles, enable them to bite and chew very rapidly. Indeed, they can give more than five 'bites' per second! This helps them to very rapidly kill and crush the hard bodies of beetles, grasshoppers and millipedes. But while fast, their jaw-muscles are not very strong. They will tear lizards apart using their teeth and claws, and will crush the skulls of mice, prior to swallowing them. Their teeth, too, are specialized in being small and numerous, with lots of pointy bits for puncturing insect exoskeletons, but no large areas for crushing and grinding. Bat-eared foxes are remarkable for having more teeth than any other non-marsupial land mammal – as many as fifty teeth in total (we humans have thirty-two).
Doggy Lives
Apart from digging up beetle grubs, bat-eared foxes also dig to excavate their dens. They need soil that is not too lose, as well as not too firm, for this. They often take over and elaborate the burrows of aardvarks and other expert diggers. Their dens will have long tunnels, and chambers for sleeping, resting and housing their babies. In fact, the adult foxes tend to make most use of the dens themselves for as long as there are small pups around; at other times, they will shelter above ground in the shade of shrubs or small trees, or out in the open.
The time for having pups is mostly late spring or early summer. When they arrive, the father will stand guard at the entrance to the den while the mother goes off to forage in between suckling the pups. Later, when they're big enough to start going out, he will also teach them how to find food and how to kill tricky critters like mice or scorpions. Finally the family will all be hunting together outside. The pups grow fast and at the age of four months they're as large as their parents, but with somewhat darker, shinier fur. The pups may stay with their parents until mid-winter, just before it's time for the next litter of cubs. Then they'll move off, sometimes sticking together in small packs.
Bat-eared foxes communicate in a variety of ways. Scent is very important to them and they scent-mark their terrain and prominent objects in them, with urine. They are not strictly territorial, though, and especially if there is lots of food available, bat-eared fox groups will approach each other and intermingle.
With their big ears, they also pay attention to sounds. They use soft whines to maintain contact, to alert pups or mates to their presence or the direction they're traveling. They will growl if confronting each other or another animal threatening them. They will bark when attacked or alarmed. Small pups chirp to call their mothers.
But although bat-eared foxes don't see particularly well, visual cues are also important to them. In particular, they use their long fur when confronted. Raising the fur all over their bodies as well as on their tails makes them look much bigger than they are! This can make a predator think twice before taking them on. If the ruse doesn't work, the bat-eared fox will flee, with great speed and agility, turning, weaving, dodging and changing direction so as to make it very hard to keep up with them. This is what got them the Afrikaans name of 'draaijakkals', 'turning-jackal'.
Unfortunately, nothing in the bat-eared fox's arsenal helps to protect them against humans. They are targeted, sometimes from the very unjust belief that they'll kill poultry. This is entirely untrue since their jaws and teeth can't deal with these at all. But they're also killed by motor vehicles, on the thousands of miles of roads traversing the subcontinent's huge, dry interior. They're also directly targeted in some places for their beautiful, long, soft fur. Lastly, they suffer from competition with domestic dogs, and are susceptible to dog diseases, most particularly rabies. Diseases can play havoc with them, eradicating them in their thousands during some years. Nevertheless they still occur over a very large range, and are adaptable enough to still live in fairly large numbers, and so are not considered to be in danger of extinction.
