Early April sees a good number of passage migrating birds. One of them is a sure winner: Yellow-rumped Flycatcher or as it is also called, Korean Flycatcher.
During this time of year the male develops an orange throat. Some individual superficially look like male Mugimaki Flycatchers and one has to pay attention to the length of the eye-brow.
From Khao Yai
The Narcissus Flycatcher is a real stunner! Lovely yellow eye-brow!
It sometimes goes through major city parks here in Bangkok though this picture was taken in April 2010 at DaFooChan Park, Guangzhou, Guangdong, China.
Here is the male Mugimaki Flycatcher. Some individuals over winter (in very small numbers) at places like Khao Yai but the majority move on further South and are best seen on passage migration in April.
From Khao Yai in January