By Melissa Wray In Greater Tzaneen Area
An arrow, some fishing twine, a modified braai grid and a mountaineer have all teamed up to help a pair of rare birds breed in the wild. The bat hawk, a rare bird lusted after by enthusiastic birders, is rarely seen because of its sparse distribution and habit of hunting for bats and small birds at dawn and dusk.
It hides during the day in leafy green trees, and appears to have a preference for nesting in pale-coloured trees which are thought to be easier for the birds to find in the twilight. Unfortunately, it often chooses blue gums, whose slippery bark is not well suited for nest building, and so the birds have been given a helping hand just outside Tzaneen.
Last year bird guide David Letsoalo observed a bat hawk pair trying to build a nest in a blue gum near Rooikoppies for several weeks. Their twigs and branches repeatedly blew away, and so David called in some extra help from Ben de Boer of Kurisa Moya Nature Lodge and ornithologist Dr Derek Engelbrecht of the University of Limpopo.
Knowing that another pair of bat hawks in the region was happily nesting on an artificial platform, Derek constructed a platform for the Rooikoppies pair, basically a braai grid with aluminium edging. The problem then became how to get the platform 14 metres up into a suitable branch in the birds' favoured tree.
Mechanical equipment used for fixing electrical cables would not reach high enough, so outdoor enthusiast Neil Haaroff was roped in. At first a fishing rod was used to try and cast a line over the branch so a climbing rope could be pulled up, but this failed. On the next try, a bow and arrow was used. Fishing line was tied to the arrow, which was shot up into the tree. Succeeding on the first go, the rope was then hauled up the tree and Neil used all his skills to manoeuvre the grid and tools up into the blue gum.
He secured the platform to the chosen branch, baited it with some twigs to give the bat hawks some incentive, and the rest was up to the birds. Within ten days the birds had started using the platform as a basis for their nest, and soon looked like they were sitting on eggs.
However, if the breeding attempt had been successful, a nestling would now be visible, but recent sightings show that the birds have abandoned the nesting attempt although they still sit in the tree near the nest.
Derek says that although very little is known about bat hawk breeding behaviour, most pairs have hatched chicks by the time the Rooikoppies pair got settled into their new nest on its platform. He speculates that this breeding attempt may have been abandoned because of the late start. The Rooikoppies pair of bat hawks brings to four the number of breeding pairs known in Tzaneen and surrounding areas of Duiwelskloof and Nkowankowa.
This is probably the highest known density of bat hawks in southern Africa. Even in the Kruger National Park, a haven for many bird species, only two or three nests are known. Derek is hoping to be able to gain more insight into the birds' breeding behaviour and success by monitoring the four pairs in the Tzaneen region.
The bat hawk, given its fondness for hunting when bats are out and light levels are low, can be confused with the migrant hobby falcon, which also likes to hunt bats. To arrange for a guided trip to see the Rooikoppies pair, call Ben de Boer on 082 200 4596.