Why Did They Need the Second Sentence Anyway?

Saw a sign today that I wanted to take a picture of, but it was raining too hard.

On a back road in the middle of a forest was an old stone building that looked like an old house, but in decent shape. There was a sign on the building that read:

THIS BUILDING IS A BAT ROOKERY.
ANYONE TRESSPASING OR DISTURBING THIS AREA IS
SUBJECT TO PROSECUTION UNDER WILDLIFE STATUTE 2.31Q.

Man, glad they told me I could be fined , else I was headed right inside that ol' bat rookery.