Mucus trails

Terrestrial slugs foUow mucus trails back to their daytime resting areas, to find food, or to mate. They foUow their own, or each other s trails. Slugs can determine the direction of a mucus trail. Predators, such as snakes or aquatic sdomyzid fly larvae, follow the mucus trail to find their prey. Laying the mucus trail is energetically expensive (Cook 1979, 1992 Davies and Blackwell 2007). 

Cottrell, J. M., Henderson, I. F., Pickett, J. A., and Wright, D. J. (1993). Evidence for GAGs as a major component of trail mucus from the terrestrial slug, Arion ater L. Comp. Biochem. Physiol. 104B, 455M68. 

Slugs and snails cause similar damage, and leave behind slimy trails of mucus. For controls, see Leaves with large, ragged holes on page 18. 

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