Part of the scenery of the Karoo is that scaffold-pyramid with its turning wheel drawing water up from underground aquifers. What would this semi-arid landscape be without these man-made “temples” to survival? In recent years, and increasingly, Karoo farmers are moving to the use of solar panels and pumps, with the water being stored in non-leaking plastic tanks. On the positive side this saves water, reduces costs for the farmer in the long run, as it saves on labour and maintenance expenses but there is a negative impact which few seem to have observed. Spillage from the old windmill system encouraged green vegetation growth around leaking reservoirs and overflow, as well as providing accessible pools of drinking water for a wide range of mammals, birds, reptiles and invertebrates.
Although our observations have been on a casual basis over several years it has become clear to us that the diversity of animal life relying on this water and food resource is high. If you want to find Leopard Tortoises on a hot summers day on the high Karoo plateau, check the windmill spillage points, where they come to drink, bathe and feed. Before the rains arrive many birds rely on this water source, from Namaqua Sandgrouse to finchlarks, and many such sites have a pair of Treble-banded Plovers in attendance, pairs of Egyptian Geese are regulars, as are South African Shelduck. These spillage points attract Karoo Toads, Boettger’s Cacos and other amphibians, often to breed.
Then, not to be forgotten, are the myriads of insects! Flights of bees coming in to drink, wasps collecting mud for their brood chambers and to hunt their spider or caterpillar prey on which their larvae will feed.
Another impact resulting from the reduction in the number of windpumps have been fewer opportunities for nesting platforms for, amongst others, Jackal Buzzards. These handsome raptors usually nest on cliff ledges and occasionally in trees but in the Karoo they have expanded their breeding range by nesting on the maintenance platforms of windpumps. We had several such nest locations in the vicinity of our home village but the move to solar pumps has reduced these opportunities. One still frequently observes Jackal Buzzards but we presume for nesting they have returned to the cliffs of the outcrops. Although we know of one active nest (the female is currently sitting on eggs) nearby that is located in a Match Poplar just 1.8 m above the ground. The windpump here has been converted to solar so this pair had an alternative but trees are few and far between in the Karoo. By being able to nest in areas without trees or suitable cliffs we surmise that numbers were able to increase- more pairs breeding in areas normally too far away from the cliff-nesting sites.
We regret not having spent more time recording the residents and parade of visitors to these unintended oases in the Karoo!
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