I have long been trying to get decent shots of Greenish Warbler which is a common winter visitor to northern Thailand, especially on mountains and even lower hills, but could never really get one because they mostly stay on upper branches and canopy. Fortunately, I came across an area where few of these nice little phylloscopus liked to come around and feed at Doi Angkhang, Chiang Mai. They seemed to favour looking for small insects and worms in Debregeasia longifolia that were flowering along the roadside.
This individual was still in a very fresh plumage. You can even see a small faint second wing bar on its median coverts which makes it look similar to the scarcer Two-barred Warbler which prefers much lower altitudes. Two-barred should also have broader wing bar on greater coverts similar to that of Yellow-browed Warbler as well.
Here you can see both flowers and fruits of the Debregeasia longifolia which is one of the most popular trees for birds on high mountains in northern Thailand. You can also see how the eyebrow starts right from the bill base unlike Arctic Warbler.
Because the plumage was so fresh, its supercilium and cheek were very yellow, which again make it look especially similar to Two-barred.
This is another individual photographed roughly about one week after the earlier bird. As you can see, it lacks the distinct yellowish tinge on its supercilium and cheek making it look more like typical Greenish Warbler which we would expect to see during winter in this part of the world, except for the median coverts wing bar which was still quite prominent.
Oh and by the way, Greenish Warblers that winter in Thailand are the nominate subspecies ‘P. t. trochiloides’. However, there are also possibilities that there might be other subspecies occurring as well. Last year, I photographed one individual which looked quite different. I’ve got to look up for the photos once again and will post them here, so we might be able to have a little discussion.