Where does a flock of starlings end and the sky begin?

This shows a flock, also called a murmuration, of starlings at sunset. The hundreds or thousands of starlings are moving almost as if they are a single body, and mostly there is a pretty clear edge to the flock. It is pretty obvious where the flock ends and the rest of the sky begins. As the flock is a three-dimensional object, this should mean that the flock has a well defined surface, which separates the volume of sky occupied by the starling flock, from the surrounding sky where there are no starlings.


A murmuration of starlings

Murmuration is my new a favourite word, it means a flock of starlings. It is one of the old English collective nouns for a group of animals, like a murder of crows, a skulk of foxes or a gaggle of geese. And as the YouTube clip above shows murmurations are simply astonishing.  The Guardian also has a gallery with some pretty amazing pictures. Thousands of starlings flying through the air as if they were a single organism. Flicking back and fore like cat’s tail, not like the thousands of bird spread across maybe 100 m that they are.


Hard drinking starlings

Taking a restI have just learnt that the European Starling can take its drink. Alcohol is metabolised, in starlings and in us, by an enzyme called Alcohol Dehydrogenase. By weight starlings have approximately 14 times as much Alcohol Dehydrogenase activity as we do. The data are in a paper by Prinzinger and Hakimi.  I will now look at starlings with new respect.

You may be asking yourself, why do European Starlings have this impressive ability to take their drink? Fruit is a major part of the diet of starlings. Fallen fruit tends to ferment of course, which produces alcohol. So it may be that starlings have evolved a high tolerance to booze to allow them to eat lots of fallen fruit without then being reduced to zig-zagging across the sky in a rather drunken way.