According to wikipedia...

Nightingales are named so because they frequently sing at night as well as during the day. The name has been used for well over 1,000 years, being highly recognizable even in its Anglo-Saxon form - 'nihtingale'. It means 'night songstress'. Early writers assumed the female sang; in fact, it is the male. The male nightingale is known for his singing, to the extent that human singers are sometimes admiringly referred to as nightingales; the song is loud, with an impressive range of whistles, trills and gurgles. Its song is particularly noticeable at night because few other birds are singing. This is why its name (in several languages) includes "night". Only unpaired males sing regularly at night, and nocturnal song is likely to serve attracting a mate. Singing at dawn, during the hour before sunrise, is assumed to be important in defending the bird's territory. Nightingales sing even more loudly in urban or near-urban environments, in order to overcome the background noise. The most characteristic feature of the song is a loud whistling crescendo, absent from the song of Thrush Nightingale. It has a frog-like alarm call.




"Nightingale"

Along with the night came my heart, black. I sing. Why sing? I am tormented driven by this need, to empty this heart of such blackness. Gravely uninviting yet many gather around to hear such a song, a song of pain, a song of betrayal, and a song of suffering. My pain is your poetry; my broken-ness is your restoration. Cursed be this song, which hinders me from sleep. And you who gather, you many stars, I sing for you. I sing beneath the glow of a melancholy moon. Your sheepish shine transforms resiliently because of my song. Such a resonance of darkness could only glorify you into majesty. My song is a cloak. He clothes the day instantly becoming night. This darkness breathes within me; my pain is alive seeking escape from within. It is frantic in its attempt, it storms the night dressed in song. Can you hear it? As the world sleeps I sing. Can you hear me? My dear song, you are my constant nightmare forbidding me rest, yet you usher the world to dream. Until the end of time my song shall remain. Until my heart has been fully emptied.

- Stefanotto (The Knight in Gale)