Many people believe that they should add red food coloring to the sugar-water preparation they make for hummingbird feeders, as an added enticement to hummingbirds. While it is true that hummingbirds are attracted to the color red, experts caution us that it may not be safe to add the dye, and it is definitely not necessary!
The current recommendation is to select a hummingbird feeder colored in a way to attract birds, and to offer those birds clear, non-colored “nectar” with a ratio of 1 part table sugar to 4 parts boiled water (cool completely before placing outside for the birds).
If your hummingbird feeder is red, purple, blue or violet, the feeder will typically have enough color to entice hummingbirds to check it out. Other colors of hummingbird feeders seem to work equally well once hummingbirds “learn” that they contain food. If you have a hummer feeder that is not colored red, violet, purple or blue and are experiencing difficulty attracting hummingbirds, try locating the feeder near some attractive blossoms (a hanging fuschia basket works well), or temporarily dress your feeder in red – perhaps tie on a red Christmas napkin.
Many countries ban the red dye commonly used as a liquid food coloring here because research suggests that it may cause hyperactivity, asthma and other allergies in humans. Studies have shown that even small doses have caused DNA damage, reduced reproductive success, reduced infant weight and caused other behavioral abnormalities.
The larger the dose of red dye used, the greater the potential harm. A bird the size of a Black-chinned Hummingbird must drink 2-1/2 times its body weight a day of the 4:1 ratio of water to sugar to meet its energy needs. If that sugar water is dyed red, the bird would take in 10 times the daily dosage that studies have shown results in DNA damage. When trying to survive in cold temperatures, or when fattening up for migration, a hummingbird might drink twice as much sugar water per day, doubling the intake of dye and the risk