A small but interesting point when it comes to sunbird prey. Sunbirds, when feeding, always insert their bills right to the back of their chicks throats. Most birds with shortish bills simply ‘drop’ food items into the wide open gape of chicks – as seen below with this Eastern Nicator.
…. and with this Sombre Greenbul feeding its chicks with fruit.
Yet sunbirds, in this case a female Greater Double-collared, always insert their bills full length, right into the throat region! Note that the caterpillar prey isn’t released at the point where the centre frame was triggered. It is always released further down the throat.
…. and here again with spider prey.
Sharp bills
If you have witnessed sunbirds feeding, you’ll know that those very sharply pointed bills are inserted at lightning speed into gapes that are actively moving and swaying around, almost too quick to capture on camera! With this happening regularly throughout the day, you’d think that the possibility of throat injuries would be very high!
The following image shows how sharp the adult bill tip is, and how deep the bill is inserted, especially when the prey is held (in this case) nearer to the base of the adult’s bill.
Two other examples of sunbirds delivering prey, this time by the shorter billed sunbird species, a female Purple-banded on the left, and male Neergaard’s on the right.
When sunbirds feed cuckoo chicks, they do the same thing, depositing prey deep down into the throat. In the example below, an Olive Sunbird feeds a young Klaas’s Cuckoo chick.
Shorter billed cuckoo hosts however just drop prey into the open gape, as seen below, where a White-throated Robin-Chat feeds a Red-chested Cuckoo chick (left), and a Brown Scrub Robin feeds a cuckoo juv of the same species (right).
Hugh’s publications include ‘Top Birding Spots in southern Africa, Roberts Bird Guide fords and second editions, Roberts Bird Guide – Kruger National Park, and Roberts Geographic Variation of southern African Birds. Hugh received an honorary doctorate for contributions to ornithology in 2012.
