You ought to be very careful not to collect any Leopard slug Limax maximus when you are collecting Spanish slugs Arion lusitanicus in your garden, because the Leopard slug is an enemy of the Spanish slug.
Some Leopard slugs looks as the dark one on the photo, while other have long spots, so they look as a leopard on the skin. A Spanish slug has a plain colour without any spots, and often their head is darker then the body.
The Leopard slug is fairly new for the Faroe Islands as well. It was observed for the first time in 2003 and has spread to Klaksvík, Funningsfjørður, Toftir, Eiði, Kirkjubø, Kollafjørður and Tórshavn.
New Norwegian studies have proved, that Leopard slugs and Spanish slugs don’t get along at all. The Leopard slug eats the egg of the Spanish slug, the small Spanish slugs and licks and bites the fully grown Spanish slug as well. The result is a great decrease of Spanish slugs in the garden.
The Leopard snail feeds on the same plants as the common black Faroese slug, so he is a very good and strong assistant to have in your garden in the fight against the destructive Spanish slug.