Angus Hardern asked about the early call of the 'lazy' cuckoo ('Spring in the air?' South China Morning Post, February 23). He has probably heard the koel which typically starts making a loud, incessant two-note 'ko-el' call in February, presumably flirting with potential mating partners. This is also the time of the year when air temperature in Hong Kong begins to climb on average. Thus many people relate 'ko-el' to spring.
Maybe the urban area is getting warmer and birds feel the heat to mate earlier than the old days. Those in the Kowloon Park area were heard calling 'ko-el' as early as January 27 this year.
C. Y. LAM
Chairman
Hong Kong Bird Watching Society
Angus Harden is wrong about having heard the first cuckoo. I have heard it for at least two weeks in the New Territories.
