Protecting Hawaii's Low to High Environments – Invasive Cannibal Snails

Hosted by Dr. Dan Rubinoff from the University of Hawaii at Manoa and colleague Dr. Brenden Holland

Hawaii's native rainforests contain plants and animals found nowhere else on Earth, and are as fragile as they are beautiful. The invasive Cannibal Snail is the likely suspect in the disappearance and extension of Hawaii's singing snails.

Snails are important in Hawaii because some species are sensitive to environmental conditions and serve as indicators of healthy forests. One of the functions of a healthy forest is to capture and hold clean rainwater. The islands in Hawaii don't have well-defined aquifers, so most of our drinking water comes from rainwater that trickles down from the mountains to the lower elevations.

Native forests are like sponges. The moss that carpets the ground and covers the trees during heavy rain periods soaks up the water so there's no flooding, then releases it slowly so we have a constant supply of fresh water.

Hawaiian forests are also a place of diversity, with lots of endemic plants and animals. Cannibal Snails were brought to Hawaii and released as a bio-control effort to control another snail, which was released in Hawaii as a food item. Unfortunately, the Cannibal Snails eat native snails instead of the pest snails.

Cannibal Snails serve as a reminder of the damage that a non-native species can do to our environment. Ecosystems are complex and made of many different components. If we replace or displace one component, it can throw the whole system out of whack.

Saving the rainforest isn't just about saving biodiversity. It's about protecting the resources we all depend on.

How you can help protect Hawaii's nature reserves:

1. Brush/clean your boots before you enter a nature preserve to remove seeds and eggs of invasive pests.
2. Never stray off the trail. Staying on the beaten path helps to protect native plants. It's also safer because many trails in Hawaii have hidden cliffs.
3. Always bring your own water. Water from streams may look clear but may contain bacteria.

Learn more about these unique islands and what you can do to protect them, visit HawaiiStateParks.org.