Nijer seed

A few months back I put up a niger feeder in my garden. Up until now nothing has been interested in it.

However the past few days its gone right down. Since I live in a flat I can't see whats on my feeders, so I use a camera trap. Anyway it seems that House Sparrows have figured out how to use the feeder! Its them eating it all.


Is it normal for sparrows to eat it? Never seen them mentioned on any niger food articles lol.

Cheers