Klipriviersberg Ridge System (KRS)
For many years and dating back to the late 1950’s, sightings of predominantly individual and occasionally a pair of Verreaux’s eagles have been reported to skirt the ridges and sporadically hunt on the bountiful Rock hyrax (Procavia capensis) commonly referred to as dassie, littering the entire ridge system and found to occupy medium to large colonies.
During 1997, I followed up on some leads pertaining to a possible nesting site within a large eucalypt tree that was situated on an old homestead that has subsequently been incorporated into the greater Klipriviersberg Nature Reserve, but no evidence thereof could be established. During the same year and over a three-month period, just on weekends, we walked the entire ridge system starting from the eastern ridge end at the R59 (Sybrand van Niekerk freeway) and ending on the outskirts of Eikenhof/Naturena close to the N1 Highway in the west. The bulk of our investigation was spent looking for possible nesting sites within the granite boulder-strewn outcrops and ridges that lay scattered along the length and breadth of the approx. 14km ridge system. Apart from the thousands upon thousands of hyrax colonies found in just about every nook and cranny imaginable, the more modernised sites such as storm water pipes / gullies and culverts, illegal rubble dump sites, municipal water reservoir infilling sites inclusive of private garden refuse heaps are all ideally suited for hyrax friendly infiltration abodes. Despite the lengthy criss-crossing of the ridges, we only located two possible sites of which one was above the suburb of Mondeor and the other on Meyer’s Farm close to the Comaro Road slipway off N12 Southern Bypass on the western boundary of the farm. Both sites had a scattering of sticks on rather small ledges of flat outcrop – to my knowledge, too small to occupy a substantial nest over a longer time period. Among the sticks were some bone fragments and the tell-tale evidence of very old and fragmented hyrax skulls and toothless jaw bones. The possibility exists that eagles may have bred there previously, but it would be difficult to determine the age of these sites, which could only be executed via DNA testing, albeit costly, to determine the age of the bone fragments.
Suikerbosrand Nature Reserve (SNR)
For as long as I can remember, there was always a Verreaux’s Eagle pair nesting on a rocky cliff on the south-eastern slopes of the Suikerbosrand Nature Reserve (SNR). Many raptorphiles, birders and bird club members alike, mentioned the eagles flying overhead, perching on rocks and in trees, as well as seeing them incubating the eggs and chicks growing to juvenile and fledging stages…by far a highlight should you visit the reserve and see them!
Prey should be well stocked for an eagle pair to take up residence in the vast reserve and having telephonically spoken to Heidelberg municipality staff, folk working at the Heidelberg Rekord newspaper and some estate agents, all were in agreement that they were very proud custodians of “their” Black eagles! Prey such as hyrax are in abundance and not deemed to be in limited supply as during the winter months dozens were seen sunning themselves huddling together on rocky outcrops. Apart from hyrax there is good stock of alternative prey such as rock rabbit, scrub hare, guineafowl and francolin, not to mention the occasional monkey troops flitting by…wary and hurriedly!
So, what happened during 2003 when the eagles vacated their nesting site for no apparent reason? As mentioned, there is abundant prey…no interference reported seen nearby, at or on the nest…yet they just upped and left.
It is quite possible that the pair was harassed on or off the nest by baboons, leopard, humans and or a caracal…the latter possibly stands little chance against a formidable pair of eagles with super sharp talons, but it may have taken their chick or juvenile whilst they weren’t in attendance – similarly occurred at Roodekrans during the double clutch breeding season of 1996, when a caracal killed the three-month-old juvenile and thereafter the carcass was entirely dismembered by jackal. Sometimes eagles may feel threatened by predators and as I have witnessed baboons harassing an eagle pair on a farm outside Bela Bela and similarly at Roodekrans, and the aggressive alarm calls by the eagles were possibly enough of a deterrent to chase off the caracal and baboons. However, eagles stand a slight chance fending off a leopard and even a much lesser chance if humans were to destroy the nest and or steal the eggs or a chick! The eagles will defend their offspring at all costs as was witnessed at Meyers Farm when Brett Gardener tried to get to the chick on the nest. Taking the eggs or a chick can thus never be excluded as humans do these things mainly for collection purposes or to raise a pet. During such occasions it is quite possible that the eagles lost their fight against the odds and once “too harassed” they will vacate such a site and move elsewhere knowing that their trusted nesting site offers no protection.