Slow Down for the Garden Slug
The garden slug, small striped slug, or black field slug (Arion hortensis) is one of the most common species of slug in Europe, found throughout the continent and on the islands of Great Britain and Ireland. It has also been introduced to North America, where its range extends along the east coast and as far west as the Great Lakes. In the wild they reside in both grasslands and deciduous forests, but they have also adapted to live alongside humans in gardens and pastures.
A. hortensis is fairly small; adults can be between 3-5 cm (1-1.6 in) in length. Coloration is highly variable, but typically falls between reddish brown, black, orange or yellow, with a bright yellow underside and dark grey or black eyestalks.
Garden slugs have a fairly short life cycle. Adults have both sets of reproductive organs are capable of fertilizing themselves or each other by injecting another slug with an extended penis called a 'love dart'. This usually occurs in the falll, and after mating, the fertilized slug lays several hundred eggs in the soil. The eggs hatch at the end of winter or in early spring, and become fully mature by the summer. Adults die shortly after mating.
Like most other terrestrial slugs, the black field slug spends most of its time under leaf litter or on low vegetation. They feed on leaves, fruits, and detritus; they are often an important part of the nutrient cycle, breaking down rotting matter to be put back into the soil or become energy for other animsl. Due to their small size and lack of protective shell, they have many predators including birds, frogs, lizards, spiders, wasps, and beetles.
Conservation status: The IUCN has not evaluated the garden slug. In many places in both its native and introduced range, it is considered an agricultural pest.
Photos
Karen Yukich
David Nicholls
Katja Schulz