Two Notes   A late spring brings the male koel, his two-note courting call shy there in the shrubbery but advertising all   the splendour of his sturdy genes, the blue sheen in his feathers, to any female flitting by should they get together.   Eudynamys orientalis is still his Latin name. Rainbird, stormbird, madness bird, his message is the same.   Two notes only may convey the anguish in his heart. All through the afternoon I hear them. Are they a fifth apart?   Eventually, there’s silence and I don’t know what to think. Has he had some luck…