Yellow Pectoral Tuft Display in Grey Throated Sunbird Anthreptes griseigularis
By Brendan Sloan
Brendan is a double Graduate in Law and Sociology but given the choice would much prefer to be in the great outdoors looking for birds. He has long been fascinated by the many endemics in the Philippines and the species changes that occur between the many islands and the great efforts and adventures required to see some of the rarer birds. In this special article he wrote for eBON, Brendan shares his observations of pectoral tufts seen in Grey-throated Sunbird.
While staying at a resort on Dinagat Island Mindanao in May 2018, I had an interesting interaction with a male Grey Throated sunbird.
As I was talking quietly with a non-birding friend on a small platform taking in the view, I noticed a nearby sunbird coming close in an agitated state. The bird was vocalizing loudly and working its way down the branches of a small tree toward where we were standing. There was no time unfortunately to reach for a recorder to capture the great singing, but the camera was at hand and I was able to take some shots.
The bird was coming very close and the interaction became intense when the small sunbird began to flare up its bright yellow pectoral tufts and advance almost to head level from only a few feet.
These bright pectoral tufts flaunted with such energy and excitement and at such a close range made for a very special nature experience and one that will be long remembered.
The bird was identified as a male Grey Throated Sunbird Anthreptes griseigularis, obviously on its own territory and keen to get a message across. It kept coming in close, retreating and coming close again. The species is a Philippine endemic, with another sub species birgitae on the islands further north, including the main island of Luzon.
The following photographs show the bright flared up tufts and hopefully conveys some of the bird’s pent up energy at the time.
A number of sunbirds, flowerpeckers, and spiderhunters are known to have pectoral tufts which can be flared from the sides of the chest rather than from the underwing coverts. They vary from bright yellow, red or orange in sunbirds and spiderhunters to white in flowerpeckers1.
The bright yellow pectoral tufts are known in the Philippine endemic Grey Throated Sunbird2. However, they are rarely observed and these may be the first photographs in the field. They obviously have a role in display and courtship, and such bright colours flared up at the chest sides are certain to catch the attention of females.
However, on this occasion there was no apparent female present and the flares were being shown in agitated fashion to two stationary people who had been present at the spot for well over 15 minutes. There was no prior movement or obvious encroachment into the bird’s territory. This opens up the possibility that the pectoral tufts are also flared as signs of warning and aggression as well as in courtship and display. It is possible that the whole interaction was triggered by an unintentional and random playback on a recorder a few minutes before. This would have taken in the local soundscape and might have had something of high interest to the male sunbird.
References:
- Sunbirds; A guide to the Sunbirds, Flowerpeckers, Spiderhunters and Sugarbirds of the World. Robert A Cheke, Clive F Mann and Richard Allen. Helm IdentificationGuides 2001
- Birds of the Philippines. Desmond Allen. Lynx and Birdlife International Field Guides. 2020