To my knowledge, there is only one LEGO set, or in this case, Minifigure, that has birdseed.
The LEGO birdseed in this case came only with the Looney Tunes Roadrunner Minifigure character. If you have ever seen the cartoon, you know that the Coyote uses birsdeed as bait, and that the Roadrunner can’t ever resist it.
The piece is modeled from another food item – LEGO popcorn. While the popcorn is white, the birdseed is yellow.
Sometimes it is challenging to remove this piece when it is put in a container. When this happens I like to use the LEGO brick separator tool to assist in removal. Your nails and teeth will thank you.