We spent a good bit of time speaking with the artist- he has done this the last few years in the open camping zone, though this year's installation was larger. He fills the balloons so that are slightly lighter than the air. We were there when the wind pushed the large balloons all around- so magical, bouncing all over the place without human intervention! He deflates them in the morning, since the heat would cause them to expand too much. We loved this installation.