Status: Not Listed
Kāhuli tree snails are tiny mollusks with colorful, elongated shells. The soft body of a snail has two parts: the foot and the head. The foot of the snail is the part of the body used for crawling. The head is where the tentacles (or stalks) attach and these contain sensory organs. Kāhuli tree snails are very small—their oblong shells are less than an inch (2.5 centimeters) in length. When young are born, they are less than a half-centimeter long.
Kāhuli tree snails are endemic to Hawaii and are found only on the island of O‘ahu. Native trees and shrubs are the best habitat for kāhuli tree snails. Non-native predators, such as rats and Jackson’s chameleons, are the greatest threats to kāhuli tree snails. One of the worst predators is actually another snail—the carnivorous rosy wolf snail (Euglandina rosea). The rosy wolf snail was purposefully introduced in Hawaii with the hope that it would kill off the invasive giant African snail (Achatina fulica). Unfortunately the rosy wolf snail much prefers the bite-size kāhuli to the giant African snail, and the planned introduction ultimately backfired.
Kāhuli tree snails have adapted to a very specialized diet. They only eat fungus that grows on the leaves of trees and shrubs.
Kāhuli tree snails are hermaphrodites, meaning they have both male and female reproductive parts. They give birth to live young. Unlike many small organisms, kāhuli tree snails have long life spans. Some of these snails live for more than 10 years. They don’t reach reproductive maturity until they’re a few years old, and after that, they only give birth to about seven offspring a year.
Kāhuli tree snails were once so plentiful in Hawaii that collectors used them to make lei. This led to the initial decline of the snails, but the biggest threat now is predation from non-native species. This problem is compounded by the fact that kāhuli tree snails are slow-growing and slow to reproduce, so they can’t replenish their numbers faster than they’re being eaten. All of the 42 kāhuli species in the genus Achatinella are either federally listed as endangered or extinct.
Hawaiian folklore mentions the singing capabilities of kāhuli. In fact, a lesser known Hawaiian name for kāhuli tree snails is pūpū kani oe, which translates to “shell that sounds long.” The singing is only a myth, but kāhuli tree snails have been the inspiration for traditional Hawaiian chants called “mele.” One chant called “Kāhuli Aku” is about the snails calling to golden plovers to bring them water. Kāhuli Aku has been set to music and is a popular children’s song.
Decimation of Endemic Hawai'ian Tree Snails by Alien Predators, American Zoologist
Global Invasive Species Database, Invasive Species Specialist Group
Hawaiian Tree Snail Conservation Lab, University of Hawaii
Pacific Islands Fish and Wildlife Office, U.S. Fish & Wildlife Service
The Living World of Molluscs
University of California Museum of Paleontology
Meet five species that felt the impacts of climate change-fueled disasters in the United States this past year.Read the Story
President and CEO Collin O’Mara reveals in a TEDx Talk why it is essential to connect our children and future generations with wildlife and the outdoors—and how doing so is good for our health, economy, and environment.Watch Now
What's on deck with the National Wildlife Federation? Check out our scheduled events—we just might be coming to a city near you!See Events
Place your order today for the themed box that delivers everything you need to create family memories while discovering nature and wildlife.Learn More
More than one-third of U.S. fish and wildlife species are at risk of extinction in the coming decades. We're on the ground in seven regions across the country, collaborating with 52 state and territory affiliates to reverse the crisis and ensure wildlife thrive.