A species of fern whose last known specimen died on the Big Island in 2015 has been found again on Kauai.
Adenophorus periens, the pendant kihi fern, is a native fern that only grows on the trunks of trees and was believed to be extinct for the last several years after all known specimens in the wild had died.
However, in May, a team from the Hawaii Plant Extinction Prevention Program found another specimen on Kauai, bringing the species back from the brink of oblivion.
“It brings a whole new chapter of hope to this plant,” said Matt Kier, botanist with the state Department of Natural Resources’ Rare Plant Program.
Kier said the survival of the pendant kihi fern is important for the preservation of Hawaii’s ecosystems. Even a small plant like the fern provides habitats for local species and helps filter water through the environment.
However, Kier said the pendant kihi fern is also particularly frail. Botanists are still puzzling over exactly how the plant came so close to the brink of extinction, but Kier said there are several possible factors, ranging from invasive species such as goats and pigs eating or destroying it, to possible rain acidification brought on by the eruptions of Kilauea, or a broader drying effect of climate change.
In any case, there were 1,280 known specimens of the plant throughout the state in 1994. By 2012, there were only 31 on Kauai and fewer than 10 on Hawaii Island.
The last known Big Island specimen was found dead in 2015, and the species was listed as “critically endangered (possibly extinct)” that same year. With the discovery of new specimens on Kauai, the plant remains critically endangered, but the listing will drop the “(possibly extinct)” addendum.
With the new specimens — Kier said five plants have been discovered across three locations on Kauai — DLNR and PEPP will work to reproduce the fern through spores collected.
“The thing about rare plants is that there’s not enough of them,” Kier said. “So, we’ll try to mass-produce them and hopefully reintroduce them into the wild, which means we may bring them back to the Big Island.”
On the other hand, Kier said there is a lot of jungle on the Big Island, and there still is a chance some specimens are alive somewhere on the island.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com
