How can you tell if a slug is native to New Zealand? By checking if its patterning looks like the veins on leaves.
New Zealand has over 30 species of native slug, all of which are leaf-veined. Introduced slugs, like the ones you’ll find eating your garden veggies, don’t have the leaf-vein patterning, and instead might be one solid colour or spotted.
You’d be lucky to come across one of these natives though, as they’re nocturnal and spent most of the day hiding under heavy things like damp logs. If you do find one in your garden don’t worry, they won’t snack on your prized cabbages. Leaf-veined slugs prefer to dine on algae and lichens that live on the surface of the leaf, rather than the leaf itself.
If you think you’ve found a leaf-veined slug, take a photo and upload it to Nature Watch for identification.