Flock
I would call a group of balloons a "bunch"
While the sounds of hummingbirds are not exactly considered music, they definitely have a language all of their own. It would be more appropriate to call them chirps then it would be to call it music. However, by listening and learning what the hummingbirds are saying, you can tell what they are doing without looking directly at them.
A group of hummingbirds is typically called a charm.
Hummingbirds come in all colors and they are about 2-3 inches high.
mutualism
HERD
tuft
herd
flock
bunch
Bunch
hummingbirds
I would call a group of balloons a "bunch"
A litter.
Herd or troop
belive a ton
A grovelling of worms.