Will the color of a bird feeder influence the number of birds feeding?

My daughter is trying this as a science experiment for school. I am looking for a hypothesis.Will the color of a bird feeder influence the number of birds feeding?
Depends on the type of bird.





Humming birds are attracted to red and only red. They feed only on the nectar of red flowers so all commercially sold humming bird feeders are red.





I can not think of another type bird that would be affected by the color of a bird feeder.Will the color of a bird feeder influence the number of birds feeding?
Probably not, but it's an interesting notion.





Hypothisis: All other factors being the same, more birds will feed at a (insert color here) feeder.





Be sure to control for other factors that affect feeder choice...food, wind direction, distance from cover, and probably a bunch of others that I haven't thought of.





Science fair judges don't care whether the hypothesis is correct, they just care that it exists.