Colours of Wildlife: Cape Golden Mole

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Cape Golden Mole

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!"

Cape Golden Mole by Willem


This little critter is a Cape Golden Mole, Chrysochloris asiatica. Once again we're with the inappropriate names! It is not really golden, and in spite of the scientific name, doesn't come from Asia. The specimen that Linnaeus himself examined and named, was mislabelled as coming from Siberia! This is rather ridiculous; these little animals all come from warm climates in sub-Saharan Africa, this one in particular inhabiting the very south-westernmost tip of the continent! I've no idea how such a slip-up happened. As for the 'golden' part, most members of the family do indeed have golden hues in their fur, but this one is more blackish. As for the 'mole' part, though these animals are mole-like, they are not at all closely related to the moles of Europe and America. Those are closely related to shrews. But the golden moles are an entirely different group, one today mostly confined to Africa. They might even turn out to be fairly closely related to elephant shrews, hyraxes and elephants. Their closest relatives might be the Tenrecs of Madagascar, which I hope to feature here soon.

Iridescent Fur


The golden moles today number about twenty species. They're all small, compact animals, the largest, the Giant Golden Mole, reaching 23 cm/11" in length and 540 g/19 oz. in weight, and the smallest, the Desert Golden Mole, often being as little as 7.6 cm/3" in length and weighing 16 g/ a tad over half an ounce. But all of them have the beautiful fur they're named for. It's not so much gold-coloured, as lustrous like gold. What is especially unique about their fur is that it is iridescent –– the only example of iridescence in mammalian fur. Like the feathers of birds like glossy starlings and sunbirds, their coats reflect different colours at different angles to the light. In the case of the Cape golden mole, its fur reflects purple, greenish and bronze colours.


This iridescence is caused by layers of pigment in the fur. Light striking the fur at different angles, travel through different thicknesses of these layers, the wavelength being shifted by differing amounts as they are reflected, thus leading to different colours seen at different angles. What we do not know, is what this feature is for. The colours are beautiful, but what use is this beauty to an animal that lives underground, coming out only at night, and even then, not having any eyes?


The answer may be that the iridescence arises 'by accident' from something that has a more practical use to the mole. Perhaps the layers of pigment actually protect the fur against abrasion as the little animal digs through the soil. But we still don't really know.


Indeed, there is much we don't know about golden moles. Their underground lifestyle makes them hard to study. Most species are extremely hard to capture alive; a few individuals have been caught and studied in captivity. They're compact little things, like round lumps, their heads and limbs quite hidden inside the smooth contours of their furry bodies. Only their naked noses and feet poke out through the fur. Their eyes have degenerated and their eye sockets are covered with skin and fur. They also don't have external ears, only small ear-holes hidden in the fur. They have no visible tails, only a few tail vertebrae being present beneath the surface of their skin. The snout has a hard, horny edge like a spade, used to push soil aside. The front legs are highly adapted for digging, being very muscular, the third 'finger' bearing vastly enlarged claws. The inner two fingers have slightly smaller claws, and the fourth, outermost finger is reduced to a small bump. The great digging claw functions like a blade cutting through the soil. The hind feet are also naked, but with smaller toes, splayed and with small 'webs' between the toes. They are used to push backward soil loosened by the forelegs, so that the mole can move forward. The digging process is very efficient, to the degree that the desert-living species are able to 'swim' through the loose sand at an amazing speed.


Golden moles eat invertebrates, mostly, such as beetle grubs, mole crickets and earthworms. A few will catch small vertebrates, indeed, the kinds that share their underground world with them, such as the small, legless digging, blind skinks, and small snakes. Some species emerge from the soil at night and catch their prey above ground, dragging them underground to eat them. They often wait just below the soil surface, being extremely sensitive to vibrations coming from above; when they sense an insect close enough, they'll jump out, catch it, and immediately draw back underground to eat it.


The Cape Golden Mole is one of the best-known species. It is mid-sized for the family, reaching 11 cm/4.5" in length. It has a dark, brownish to blackish fur, with the noted iridescent effects. Most distinctively, it has a white 'band' of fur at the front and stretching around to each side of its snout. Its original habitat is loose soil in the 'fynbos' region of the Western Cape of South Africa, indeed occurring over almost the entirety of that province. It is one of the most adaptable golden moles and quickly learnt to live in human gardens. They're sometimes persecuted because they may disturb the roots of delicate plants and kill them; however, they also serve a valuable function by eating the beetle grubs we call 'snywurms' (Afrikaans for 'cutting worms') that cause direct and much more severe damage to roots and bulbs, and other insect pests. They themselves don't eat plant foods at all. Moving just below the soil surface, they push up ridges and small mole-heaps. Some gardeners may dislike these 'disfigurations' to their gardens, but if it were me, I would be only too happy to know that there were these beautiful little things living down there!


These little critters need a lot of food to sustain their lifestyles. It is comparatively very much harder to move around by digging through soil, than it is to walk or run above-ground. The Cape golden mole eats 70 times its own weight in invertebrates each year. It is also able to go into torpor, a state like that of hibernating animals, every day, to save energy. 'Sleeping' like this, it appears cold and dead, but re-awakens in time for its nightly bouts of activity.


We know little more about these mole-like things, except that they seem to occur solitarily, each animal defending its own tunnel system, and that they have on average two babies each season.

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