“COMPARISON OF FEEDING ECOLOGY OF VON DER DECKEN (Tockus deckeni) AND NORTHERN RED-BILLED (Tockus erythrorynchus) HORNBILLS DURING THE BREEDING SEASON”

The feeding ecology of two Red-billed hornbills and two Von der decken hornbills’ using camera images obtained during the breeding season were studied in Mpala Research Centre, Nanyuki. Red-billed and Von der decken hornbills have different feeding patterns, Red-billed being more carnivorous at 43.94% as compared to Von der decken hornbill  which was28.42% carnivorous and 10.03% frugivorous.

 Red-billed and Von der decken hornbill showed almost the same trend as the nesting days progressed on. There was a sharp increase in feeding rates during the egg laying period. This is because the female required a lot of nutrients for egg formation (Meijer & Drent, 1999).When the female is incubating the eggs, the male will be feeding the breeding female only therefore energy demand is low during that time. There is a steady increase when the eggs have hatched; the general trend is for rates to be considerably higher during the nesting period than during incubation, to rise at a peak when the chicks are growing at their highest rate. The male hornbill continues to ferry food and some lining material during this period (Kemp, 1995).

The trend of rate of deliveries throughout the day was almost similar in the two species. Early mornings and late evenings had the lowest frequency of deliveries to the nest. This is because of low temperatures and sometimes it can be really dark in the evening obscuring vision.