It’s been just over three weeks since we first found the Southern Ground Hornbill nest in the south-eastern parts of the reserve.
As per the protocol, we have not visited the nest site since then and have given the flock a reasonable amount of space in our best attempt to allow them to remain settled and undisturbed during this sensitive time.
Upon reporting the nest to the Sabi Sand management, they were the only other people to view the nest, purely to assess it for research purposes. Other than that we have seen members of the flock fairly regularly, in the general vicinity of the nest, as they set about foraging for food in the long grass and many puddles that have formed after the rains.
A few days ago, we were alerted that the Reserve Ecologist would be returning to reassess the nest and check on the progress of the brooding female. During these rare opportunities to visit to the nest, impact is kept to a minimum and so, along with the Sabi Sand inspector Robin, just three of us headed down there. We had a maximum of fifteen minutes to be at the nest and had to be careful not to leave too much of our scent behind. The objective of this particular visit was to see firstly if the nest was still being used and that the eggs had not been predated on or abandoned and secondly, if all was well, to see if the eggs had hatched.
Ground Hornbills practise a fairly common breeding behaviour amongst large birds in that they will lay two eggs (most of the time) but only raise one chick.
The idea behind this is that the second egg is more of an insurance should something happen to the first one. Both eggs will hatch but the second to do so will be disregarded by the flock as they invest all their time and energy into the first chick.
For a species whose numbers are unfortunately still declining, this breeding behaviour gives us the perfect opportunity to lend a helping hand and boost the population: a few conservation centres have started initiatives to remove this disregarded chick from the nest and rear it in captivity instead. This essentially takes that chick’s chances of survival from zero to somewhere around 50%. After being hand reared, these birds are reintroduced to wild areas where they then have a chance of joining a flock and breeding themselves. To find out more about this, there is some fantastic information on the Mabula Ground Hornbill Project website.
As we slowly approached the nest, Robin explained that if the second chick had indeed hatched, he would carefully remove it and place it into an incubated and humidified box that he had in his vehicle. From there, the chick would be transported to one of these rearing centres nearby.
Of course, there was the chance that the nest would be empty, as he explained that another nest he had previously monitored was in fact raided by a hungry leopard so we weren’t quite sure what to expect!
The nest is situated in an ideal spot; a large natural cavity, about three meters off the ground, in a dead leadwood. Robin placed his ladder at the base of the tree and as he did so, flushed the female off of the nest. Our fifteen minutes started now! He climbed up and peered inside and turned to us with a big smile and gave us the thumbs up. Two chicks were nettled in the leaf litter in the base of the cavity!
We all had a brief chance to peer inside, all the while being cautious not to disturb any part of the nest. Robin then went back up and carefully carried the smaller of the two chicks into a pouch, down the ladder and into the incubation box. The female shortly returned back to the nest and settled down there once again.
During the next few months, the flock will dedicate all their time to raising and protecting their chick while providing for the mother who will continue to brood on the nest for the next few weeks. The second chick will be given its best chance of survival at the rearing centre and hopefully reach adulthood and be released into the wilderness to raise more Ground Hornbills of its own one day.