The redbreast warbles still but is content
With slender notes and more than half suppressed:
Pleased with his solitude
Its the middle of winter and a robin has been regularly singing a rather wispy song in the midnight hours outside my flat. The flat's in a truly urban setting with a constant orange glow from street lamps and onoff security lights that respond to windblown branches and happy laughing students, returning to their beds! But my robin (and others like him) must be using valuable energy on what seems of little use.
Quite possibly its down to a mix of factors. Robins were originally a woodland species. As such they don't mind poor light and are happy for example, singing from a shadey perch deep within a tree. In rural settings they're also one of the first birds to start the spring dawn chorus. In addition unlike many birds, they sing in winter daylight hours to defend their territories. This winter song (as acknowledged by Cowper) is far more wistful and melancholic, than their more energectic spring time notes. Even given their origins and normal behaviour though, it still doesn't explain singing in the “dead” of night!
Urban areas tend to be quieter at night, with much less traffic noise. Research in Sheffield, suggested this quieter time was likely to be stimulating robins to sing at night. But research in 2014, in southern Germany has thrown this into doubt. There a study of 6 common songbird species (including robins), found the start of dawn singing was influenced by artificial lighting and not less traffic noise. Even there though, robins only sang on average 20 minutes earlier than usual, and not several hours early!
Interestingly the German study seems not to have considered the effect of security lights as well. Is it possible that my robin having found a reliable food source and plenty of cover, he (or it may indeed be a she) is stimulated by security lights, as well as street lighting, to expend more energy in protecting it, by both day and night? The nearby main road is also considerably less busy at night! More research needed perhaps??Marion