The photos (feature photo plus the ones below) are from a ride a couple of days ago, right at the transition of the Challenge from Part 1 to Part 2. The feature photo shows the lights at the local ball field.
I happened upon the above sign at the same park, which sounded pretty strange to me. I actually thought it was a joke. After getting home I did some research though, and according to the University of Vermont website, this is an actual thing. It sounds like “jumping” is a bit of an exaggeration. It’s more like “thrashing around”. This was in an area of the park where they were dealing with other invasives, although mostly of the plant variety. And here I always just thought worms were worms.