Dear Brendan
It's largely due to the construction work in progress at the MTR site. Daily incessant flow of trucks
with great noise disturbance on the airfield side of the road has greatly affected the habitat there. This winter is, according to my observation, also poor in thrushes in number as well as variety, Red-flanked bluetails (haven't seen one) and Red-throated flycatchers.
S L Tai