MADISON, Wis. — Wisconsin Department of Natural Resources wardens are warning of the harmful effects that balloon releases have on marine wildlife.

A beautiful release of a collection of balloons is a popular way to celebrate, commemorate or memorialize a person or event. But, what goes up, must come down. And when the balloon litter reaches the Great Lakes it can prove deadly for native and migratory birds and other species. They can even cause problems for boats.

DNR marine warden Dave Allen and warden Lynna Gurnoe have been picking flattened balloons out of Lake Michigan. They say they picked a dozen balloons from the lake on a single day.

The DNR has a simple message. If the balloons are used to make memories, just keep them. Otherwise, the old balloon remnants can pose threats to wildlife which can choke or drown when they try to eat them or get tangled in the strings.