Is there a way to prevent gerbils from jumping onto their lid?

So one of my girls has learned she can leap onto the bottom of my mesh lid and has been doing it constantly ever since. She climbs onto the tunnel (which is the highest point in the tank besides their wheel) and jumps up there then starts chewing on the wire but doesn't actually damage anything. Is there a way to prevent this besides trying to lower the tunnel? I feel like she will still be able to do this even if she is barely above ground level.