Leopard Slug Fact File
The leopard slug has an elongated body covered in a slimy mucus. Their skin is colored light brown and patterned with black spots and stripes. This pattern gives them their name.
Unlike their relative the snails, slugs lack a visible shell. Instead a flat shell is present under a protective shield called the mantle.
At the front of the head is two pairs of tentacles. The top pair are used to sense light and work as the eyes of the snail. The other pair are closer to the ground and are used to smell.
An average leopard slug will grow to 20cm (7.9in) long.
Leopard slugs are omnivores. They feed on a range of fungi, plants and deceased animals. These animals have also been known to consume other slugs. Feces of some animals are also consumed.
In human inhabited areas they have been known to eat food left out for pets.
Wild 2-4 years
— AD —
Leopard slugs have been introduced to every continent except Antarctica. Their native range was in Europe though the exact extent of their original range is unconfirmed.
At present they can be found in the following countries in Europe – Albania, Andorra, Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czechia, Denmark, Estonia, Finland, France, Germany, Greece, Guernsey, Hungary, Ireland, Isle of Man, Italy, Jersey, Latvia, Liechtenstein, Lithuania, Luxembourg, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, Ukraine and United Kingdom.
Introduced populations exist across much of Australia, New Zealand, Mozambique, South Africa, Canada, Mexico, United States of America, Argentina, Brazil, Chile, Colombia, China, Japan and India.
They make their home in forests in their native range. In their introduced range the leopard slugs are primarily found near human dwellings.
Leopard slugs are hermaphrodites. Both individuals will have male and female reproductive organs and produce offspring after a successful mating.
They have an interesting mating technique. Pairs will climb together up a tree or on to a rock. They then lower themselves down on a mucus rope and intertwine their bodies. This movement is always done in an anti-clockwise direction.
Once their bodies are intertwined their penis will come out from the reproductive opening on the side of their head behind the antennae. They exchange sperm and then climb back up on to the tree with one eating the mucus on which they were suspended.
Sperm may be stored for months or years.
Their eggs will be laid in the soil in groups of up to 100.
The eggs will incubate for 20 days after which they hatch. Young slugs appear as a miniature version of their parents.
Leopard slugs are primarily active by night. They are often seen after rain. Their activity can be noticed due to the trails of slime which are left behind.
Predators and Threats
Leopard slugs will be killed by humans mainly to stop them eating plants in a yard.
Due to the way they have spread across much of the world they are not under any major threat.
The leopard slug has spread to every continent except Antarctica.
By Lokilech – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2796978
By Didier Descouens – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=27711151
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