Footprints following varg suspicious dirt pile disappear when unloaded.

When you get a hunt with a tooth in it, it will usually have tracks following it. Sometimes I notice varg hunts without these tracks following them, usually in spots where I've recently noticed the same hunt but with tracks. I'm attaching screenshots to show the difference.

I have noticed this happening when I unload the suspicious dirt pile and reload it. When I tested this, I saw the footprints fading away when I got back.

With footprints (before unloading):

Without footprints (after unloading):