The southern ground hornbill is probably one of the more iconic bird species you may encounter on safari here at Singita Sabi Sand. With their striking black plumage, white primary feathers and bright red eye and throat skin they are indeed a very special sighting. That being said, they are not often encountered as these birds live in extremely territorial groups occupying territories as large as 80 – 200 km2. Their population within South Africa is estimated at 1 500 birds spread across an estimated 430 groups. Threats that the species face outside of protected areas are mostly anthropogenic including poisoning, habitat loss and hunting for traditional medicine. The birds themselves are also slow breeders, only reaching sexual maturity at eight years and while the dominant pair in a group breeds every year, only an estimated one chick in every six years survives due to an extremely high juvenile mortality rate. Southern ground hornbills only lay two eggs, with only the first hatched chick surviving, the second egg is more of an ‘insurance policy’ should something happen to the first chick within its first few days of life. So to assist in the conservation of the species a southern ground hornbill monitoring program was set up in the Sabi Sand Wildtuin (SSW).
While working for the SSW conservation team, I was privileged enough to be involved in and eventually run this conservation project, one that I became extremely passionate about. The project was headed by the Mabula Ground Hornbill Project (MGHP) and was first brought into the SSW in 2013. The project initially only involved the monitoring and data collection regarding population demographics. Once enough was known about the number of groups, the distribution of each group and the composition, the difficult task of locating their actual nests was then started. Over the next few years nests were identified with two being on Singita’s property. There are 10 groups in the SSW of which we at Singita Sabi Sand see two of these, one group of five in the north and the largest group in the reserve consisting of eight individuals which occupy the entire central and southern sections of the property. To further assist in the conservation efforts the SSW became an active participant in the nest harvesting program in 2017 whereby the redundant second chick is removed from its nest immediately after hatching. And seeing as two nests are found within our property, Singita then became an active participant in this critical project. The second chick is then taken to the MGHP headquarters where they are raised with minimal human contact. New groups are formed and these groups are then eventually released back into areas where these birds once used to occur.
The process of harvesting and ‘candling’ is a fascinating one and occurs as follows: Through regular nest checks, recently laid eggs are soon discovered. The eggs are carefully removed from the nests with their position and orientation maintained throughout the process. This is to prevent excessive movement of the embryo and therefore reduce the risk of damaging blood vessels. The eggs are weighed, and the length and breadth of each egg is recorded. Each egg is then candled under a blacked-out hood by placing a LED light under the egg, illuminating the inside of the embryo. The age of the embryo is then determined, which enables one to estimate when the eggs will hatch and when the right time will be to harvest the second chick. The eggs are placed back in the nest and this is all done as quickly as possible and with the utmost sensitivity to reduce the amount of impact and disturbance on the adult birds near the nest.
So far, two chicks have been harvested from one of the nests on Singita in both 2017 and 2018 and we know that there are eggs currently waiting to hatch in the same nest so it is looking likely that a successful harvest will occur for the 3rd year in a row. While the process is a slow one, the future of these incredible birds is a bright one.