Large Red Slug – Arion (Arion) rufus

Length 60-140mm. I often see these in my garden after dark, or after heavy rain when they come out to feed or look for a mate. It can be one of those pests which just love to munch through your garden, but sometimes visiting frogs and toads help to keep them down. I noticed for the first time when I was photographing this particular individual how when he or she was bunched up to protect itself, it began rocking from side to side, which can be a characteristic of this species.

I find with this type of slimy creature, especially after rain, you have to be conscious of the light and how you use flash as you can get many blown highlights which does not always look nice. I used the natural light in most of these images, but of course a good flash diffuser could also be used if the area was shaded or the day overcast.

This medium-sized to very large slug is also called the ‘Great Red Slug’, ‘European Red Slug’, amongst other names. It has a differing range of colour forms, from yellow, orange, brown and rarely black.  It has a striped fringe along the foot which is characteristically brighter than the body colour, usually bright orange or orange-red. The sole is often paler than the body sides. The tubercles are very course. The mucus is thick and sticky, and usually clear, although it may have an orange tinge. Similar to the Large Black Slug (Arion (Arion) ater), which is the duller of the two species, with a darker foot fringe.

They feed on carrion, dead and alive plant material, and fungi. They hide under rocks or logs during the day, and come out during spells of rain or at night to feed. It is found in many differing sites where there is plentiful vegetation like woodlands, fields and gardens. Most likely native, common and widespread in southern Britain.