Regarding the red dye myth..(undetermined)
http://www.snopes.com/critters/wild/reddye.htm
I am a hummingbird afficianado. I've had a researcher come to my house,
catch and record information (weight, feathers, size, etc) and release the
little critters. Nothing was ever mentioned about red dye. And I have been
using red dye for years, and know for a fact that I have hummers returning
year after year.

Perry