An effort to draw attention to the environmental impacts of the Indy 500 balloon release has been cut short.

A billboard decrying the race day tradition was unveiled this week on W. 16th Street, and was scheduled to be on display until April 14.

But this afternoon, Danielle Vosburgh, co-founder of Balloons Blow and the Florida woman behind the campaign, received a message from someone asking why the billboard was already gone.

"Initially, I was like what the heck, but it’s kind of funny," said Vosburgh, who added that she's not deterred and is looking for a different avenue to publicize her cause in Indianapolis.

The billboard showed an image of a balloon as well as a photo of a balloon hanging from the beak of a bird. The text read "BALLOONS POLLUTE AND KILL. #StopLitteringIMS BalloonsBlow.org."

Vosburgh told IndyStar that a representative from OUTFRONT Media, which owns and operates the billboard, told her that someone from IMS called the billboard company's office and claimed that the billboard's message was an attack ad. OUTFRONT Media then took down the billboard.

IMS spokesman Alex Damron, though, would only say Monday that, "We did not reach out to the billboard company to ask for it to be taken down."

Damron later clarified that no one at IMS has spoken to with the billboard company, nor had anyone been authorized to speak to the company.

OUTFRONT Media did not respond to a request for comment.

IndyStar first reported on the billboard on Monday afternoon. A few hours later, it received reports that it had been taken down.

This is third billboard that Vosburgh has funded to raise awareness about balloon releases and their danger to wildlife. Her first was stationed outside of Disneyworld in Orlando, Florida, and the second was debuted in August near the University of Nebraska-Lincoln.

Vosburgh said she was also preparing to fund a billboard near Clemson University, until the college announced last year that it was abandoning its balloon release.

According to Vosburgh, U-NL and IMS are the last two instiutions to orchestrate large-scale balloon releases.

Vosburgh grew up cleaning the shores of southeast Florida. Over the last decade, she said she's noticed more and more balloons washing up on the beach. She and her sister founded Balloons Blow, a website dedicated to educating the public on the risk balloons pose to wildlife and the environment.

The problem, Vosburgh said, is that after balloons are released, they ultimately make their way back to earth where they're not much different than any other kind of litter.

"We need to dispose of our garbage properly," she told IndyStar last week. "You wouldn’t throw balloons on the ground so why would you let them into the air where they’re going to land somewhere else?"

The Indianapolis Motor Speedway has released thousands of balloons as part of its opening festivities almost every year since 1947.

Alex Damron, the Speedway's director of communications, told IndyStar in 2018 that the balloons were made of an organic, biodegradable rubber, and that IMS had no intention of abandoning the release.

"We have not considered an alternative. The balloon release is a cherished piece of our pre-race ceremony and will continue to be part of Race Day," he said at the time.

In response to the latest development, Damron last week emailed this statement to IndyStar: “The balloon release remains a part of the Indianapolis 500 pre-race program. However, we continue listening to and evaluating feedback from multiple perspectives on the topic. We’re reaching out to several stakeholders and talking with experts to fully understand the impact of this practice and determine its status in the years ahead.”

Experts told IndyStar that the balloons can take years to degrade and pose a real threat to wildlife, which mistakes the latex for food. The U.S. Fish and Wildlife Service also routinely requests the public not to release balloons.

Emily Hopkins covers the environment for IndyStar. Contact them at 317-444-6409 or emily.hopkins@indystar.com. Follow them on Twitter: @_thetextfiles.

IndyStar's environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.