Endangered Kāhuli

Last year 2023 was officially dubbed as “The Year of the Kāhuli” in Hawaii. Kāhuli is the name of the Hawaiian land snail in ‘ōlelo Hawai’i, the Hawaiian language. Tiny creatures that have many different shapes, sizes and colors. When asked, a handful of Lahainaluna students offered the following associations with the word “snail”: “slow,” “slimy,” "gross,” “annoying,” “cute,” ect. Though they may be slimy and annoying, they are also responsible for maintaining the lush environment of these islands. That is, Hawai‘i’s ecological health rests on the tiny “shoulders” of snails, more specifically the land snails endemic to the Hawaiian islands.

Kāhuli have always been prominent in Hawaiian culture. They feature in their own stories wherein they sing beautifully in the trees. Their shells were used in lei and jewelry that was of great importance to Hawaiian people of status. Queen Lili‘uokalani once owned lei pūpū kuahiwi ("Land Snail Shell Lei") made of the shell of many different land snails, including the Achatinella land snails. This lei is currently held at the Bishop Museum in Kalihi, O‘ahu.

Achatinella along with the Partulina genus are kāhuli belonging to the Achatinellidae family. Many know them as O‘ahu tree snails or pūpū kani oe. They have many different names and come in many different sizes, patterns, and colors. Both generally have smooth and glossy shells, which are conical (like an ice cream cone) shaped, and both play critical roles in Maui's ecosystem.

Kāhuli are nocturnal and known to live on land in the trees, bushes, and the forest floor of the mountains and valleys on our island. They live on one tree their whole life, not once leaving their trees unless they are blown away. All 40 or so species of the genus Achatinella are listed by U.S. Fish and Wildlife Service as endangered.

Despite this fact, little can be done to regulate the tide of their main predators in the islands, namely, rats, Jackson's chameleons, and Rosy wolf snails. These predators were all introduced to the Hawaiian islands with the arrival of foreign trade and biocontrol against other invasive species.

Kainoa Pestana, conservation manager at Pu‘u Kukui Watershed preserve (PKW) said that he tries to help people understand the ecological importance of the snail with the catchy slogan “No snail, no whale.” He explained the whole chain of events that will damage the Hawaiian ecosystem if these snails were to go extinct.

First the kāhuli eat and clear the leaves while their feces acts as nutrient rich fertilizer for the plants. Without the obstruction on the leaves the plants can photosynthesize better and produce more plants effectively. If the snails do not do their job, the plants will soon die off. If that were to happen there would be no roots to hold the dirt together in the valleys and mountains. When it rains, dirt would runoff into the rivers and oceans. The debris from the run-off would prevent new limu growth, leading to the small fish having no food. Without the small fish, there is no food for the bigger fish. Long story short: “no snail, no whale.”

Pu‘u Kukui Watershed preserve’s job is to protect and maintain a steady supply of fresh water “so that there is enough water in 500 years from now for us to drink and use” Kainoa stated. The threat to snails, again, is a threat to native Hawaiian plants. Kainoa mentioned an important Hawaiian proverb “Hāhai nō ka ua i ka ulu lā‘au,” which he translated “the rain follows the forest. No forest then no rain.”

Without rain the island will become just like any other rock in the middle of the ocean. When people think of extinction they imagine it happening over a long period of time. But all of this could happen in a single lifetime, and after the loss of a single organism: the kāhuli.

To stop this from happening the Pu‘u Kukui Watershed preserve on Maui protects the fragile native Hawaiian rainforests by protecting native fauna and flora, endangered or not. They are the largest preserve on the Hawaiian islands with more than 9,000 acres of regulated and protected land.

The division of forestry and wildlife in the Department of Land and Natural Resources (DLNR) in the State of Hawaii has authorized $2,080,000 in funding for Pu‘u Kukui Watersheds 2024-2030 long range land management plan. This is part of the Natural Area Partnership Program (NAPP) which encourages the management of private lands that contain some of Hawai‘i’s most intact ecosystems and endangered species.

The PKW has built a snail enclosure to protect the rare native tree snails from predators and habitat destruction. One of PKW’s management plans is on Pu‘u Keka‘alā‘au at an elevation of 2,358. This is one of many special ecological areas for the land snails.

PKW continues to give these kāhuli a fighting chance by joining with SEPP (Snail Extinction Prevention Program) to save these endangered snails and record the emergence of new species. SEPP encourages the reproduction of hawai‘i's rare land snails by providing predator-free living conditions with optimal laboratory controlled enclosures. Kalena Lee-Agcaoili said, “Part of our work is to make sure that these kāhuli get to do what it does, to give them the space they need to live.”

During the 2022 Lahaina wildfire that went above the L at Pu‘u Pa‘upa‘u, some snails went extinct . Most people believe nothing lives up there, that fires don’t reach the rainforests, but the kāhuli does.Because these snail species are on the endangered species list, every snail could cost upwards of 20,000 dollars for their loss. The way the PKW and SEPP calculate the worth of these snails is by going up there and walking through the forests to survey and collect data on how many there are and where they are. The fewer there are, the higher their worth.

To help save the kāhuli, you people can make a small donation to the Pu‘u Kukui Watershed preserve. It’s also helpful to simply just recognize their presence and to talk about them with others. Like the kāhuli, impact has little to do with visibility. If creatures as small as these Kāhuli can make such a difference, then think of how big of a difference you can make. If we don’t acknowledge the importance of the kāhuli, the next generation may not grow up to see or hear them singing again among the trees.