A Bermudian species of fern is on the edge of extinction, according to an international “red list” of endangered species.

The Governor Laffan’s Fern and the Bermuda Shield Fern have both been included in the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species, which was released earlier this month.

The list is considered the global standard for accessing the risk of extinction for endangered species.

It categorises the Governor Laffan’s Fern as extinct in the wild — the last step towards extinction — while the Bermuda Shield Fern has been listed as endangered.

Biodiversity officer at the Department of Conservation Services, Alison Copeland, said that several Bermudian species such as the Bermuda Skink and the Cahow already appear on the list, along with Bermuda Cedar, Olivewood and Bermuda Palmetto, but the majority of Bermuda’s endemic plants have never been assessed.

However, that is set to change this year with nine Bermudian species including Bermuda Peperomia, Bermuda Sedge, Darrell’s Fleabane and Bermuda Bean being assessed this year.

“In order to be listed on the IUCN Red List, species must meet a list of strict criteria,” Ms Copeland explained. “We need to know as closely as possible how many mature individuals remain in the wild and if they are reproducing. We also need to know why the species has declined, what the threats to it are, and if those threats can be stopped.

“We enter all the variables into the Red List assessment and it weighs the positive and negative data and produces a conservation status. The options for status range from Extinct in the Wild, to Critically Endangered, Endangered, Vulnerable, Near Threatened or of Least Concern.”

The Governor Laffan Fern was last seen growing wild in Bermuda in 1905, and repeated attempts to rediscover it in the wild over the last 100 years have been unsuccessful. However, the species has survived to present day as a potted plant. It is hoped that Red Listing the species will attract interest and much needed funding for recovery.

The Bermuda Shield Fern, meanwhile, can be found on damp rock faces and at the mouths of caves and rocky outcrops in mature woodland. It is only known to occur in three locations on the Island and — because it is endemic to Bermuda — these three locations make up its entire global distribution.

The quality of the fern’s habitat is also considered to be in decline due to the impact of human activities and invasive species.