"Balloons are not biodegradable," Kitty Block, president and CEO of the Humane Society of the United States (HSUS) and Humane Society International (HSI), told The Dodo, adding that there are alternative decorations that people can use at parties that are less harmful to our fellow creatures. "We have long discouraged the use of balloons for celebrations and other events, because of the direct threat of harm or death they pose."
The U.S. Fish and Wildlife Service (USFWS) has also been trying to raise awareness about the dangers of releasing balloons by showing where the balloons end up. One photograph, among many collected by USFWS shows a seabird's body tangled up a blue balloon string still attached to a scrap of black rubber.