Pacific Banana Slug

Ariolimax columbianus

Pacific Banana Slug

Ariolimax columbianus

Other Common Names
Banana slug

Behind-The-Scenes, Presentation Spaces

Other Common Names

Banana slug

At the Aquarium

Behind-The-Scenes, Presentation Spaces

Appearance

As its name suggests the Pacific banana slug resembles a ripe banana. Some are bright yellow while others are greenish, brown or white. Some Pacific banana slugs have dark spots while others have few or no spots. This coloration helps banana slugs blend in with the leaves on the forest floor.

As one of the largest terrestrial mollusks, the Pacific banana slug may grow up to 7 inches or longer.

This species travels on a muscular foot which also serves as the slug’s stomach. A little hole on the side of its head provides their single lung breathing access. The radula, a long thin row of microscopic teeth, is located at the front of the stomach.

A set of 4 antennae can be found on the head, helping the slug navigate across the forest floor. Acting as eyes, the top two longer antennae sense light and movement. The two bottom shorter antennae are for feeling and smell.

Habitat

Temperate rainforest

Diet

Dead plant material, fungi and animal droppings.

Life History

Despite being typically active year-round the Pacific banana slug tends to be restricted by drier summer weather and is more active during cool moist nights.

Like most other slugs, Pacific banana slugs are hermaphrodites, meaning individuals contain both sexes.

The slug secretes a layer of mucus containing pheromones that attract other slugs for mating. Slugs mate and lay eggs throughout the year. Up to 75 translucent eggs are laid in logs or on leaves.

The adult Pacific Banana slug provides no further care for their young. Eggs hatch after 3 to 8 weeks.

IUCN Status

Not Evaluated

Ecosystem & Cultural Importance

As detritrovores, or demposers, Pacific banana slugs play an important role in nutrient cycling and breaking down organic matter in forest ecosystems. Through their consumption of plant material and animal droppings, banana slugs also disperse seeds.

The Pacific banana slug are prey for a variety of species including racoons, garter snakes, waterfowl, and salamanders.

In redwood forests the Pacific banana slug has a mutualistic relationship with redwood trees. Banana slugs eat the young shoots of other trees and plants while ignoring redwood saplings. By removing the competition for shade, redwoods grow taller creating a cooler microclimate. This gives Pacific banana slugs the cool and moist environment they need to thrive.

Pacific Northwest from southeast Alaska to central California

The pacific banana slug can be found in areas on the west side of the Cascades to the coast and in Umatilla county.

Muscles in the foot contract in waves, pushing the slug forward at a speed of up to 6 and half inches per minute.

Pacific banana slugs constantly secrete a layer of mucus over their bodies. Not only does this mucus keep the slug moist, it also acts as a defense against predators.

Citations & Other Resources

Vlach, J., and Oregon. Insect Pest Prevention & Management, issuing body. 2016. Slugs and snails in Oregon : a guide to common land molluscs and their relatives. Oregon Department of Agriculture, Insect Pest Prevention & Management.
National Parks Service. N.d. Banana Slug. Muir Woods. https://www.nps.gov/muwo/learn/nature/banana-slug.htm
National Parks Service. N.d. Banana Slug & Millipede. Redwood. https://www.nps.gov/redw/learn/nature/banana-slug-and-millipede.htm
Oregon Forest Resources Institute. N.d. Pacific Banana Slug. https://oregonforests.org/wildlife-oregons-forests/pacific-banana-slug

Pacific Banana Slug

Pacific Banana Slug

Other Common Names

At the Aquarium

Appearance

Habitat

Diet

Life History

IUCN Status

Ecosystem & Cultural Importance

Citations & Other Resources

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