One morning a couple of weeks ago I stepped out on the deck overlooking the backyard. Something shiny in the sun caught my eye. It was an aggregate of slime trails left by slugs on a long brick. Like the railroad tracks converging at a central station, they were all directed to an adjacent apple core; obviously a favorite slug food.
When I started writing this a half an hour ago, I realized I should have looked under the brick to find the slugs that had left their slime on it. I got curious to see if I could find any 2 weeks later. Grabbed my camera and went outside. Sure enough, there were 2 Deroceras reticulatum, one in the mud and the other stuck on the underside of the brick. I don't know how they survive the freezing temperatures we've been having in the evenings.