There is a long-established tradition in Britain of writing letters to The Times newspaper to announce hearing the first cuckoo in Spring - an event which also inspired a well-known musical composition by Delius.. It is in that spirit that I report hearing the first koel in Spring this morning. The koel is in fact an Asian member of the cuckoo family, whose distinctive two-note cry is commonly heard in Hong Kong's rural areas, and indeed elsewhere in Asia; one can be heard in the background of the Aung San Suu Kyi biopic "The Lady", filmed in Thailand. Its meaning is presumably the same as that of most bird calls: "hey babe, let's make some eggs together".
There is something endearingly loopy about the koel's cry, particularly when the bird repeats it several times, each at a slightly higher pitch, until it reaches a demented crescendo, only to pause before repeating the entire sequence a minute later. You can hear samples - along with the sounds of other local birds - at the Hong Kong Bird Watching Society website.