I noticed that as well Andrew, it will be there right after a post, sometimes, then I come back to a post later and it is gone. I was wondering if it was some of my computer settings that was doing it.
On the beetle bug. There are a number of larvae that have twin "tails" that bream feed on. On my post about the motor oil; the bait that was ( is ) the most productive for us was a straight, twin tailed grub a fair bit like the Beetle Bug.