First local extinction in the U.S. due to rising sea levels

Goodbye to the first plant species to disappear due to rising sea levels in Florida. A team of researchers declared it locally extinct, documenting its decline in the Florida Keys

Climate change is the defining challenge of our century, bringing with it extreme consequences such as record-breaking temperatures, droughts, biodiversity loss, glacier melt, and rising sea levels.

In the United States, we have witnessed the first local extinction of a species attributed to rising sea levels. The affected species is Pilosocereus millspaughii, commonly known as the Key Largo tree cactus, which is found on some Caribbean islands, northern Cuba, and the Bahamas.

In the U.S., a single population was identified in 1992 at one site in the Florida Keys, an archipelago off the coast of Florida. This population no longer exists.

A recent scientific study published in the Journal of the Botanical Research Institute of Texas confirms this extinction. The study tracked this sole group of Key Largo tree cacti, documenting their decline.

Initially, there were 150 cacti found in the region, but over the years, that number plummeted to just 6 by 2021, the very last of their kind.

The drastic decline was due to rising sea levels and saltwater flooding, as well as other factors such as high tides and soil depletion caused by hurricanes.

Emergency intervention

In 2021, an urgent intervention was needed. Researchers attempted to rescue the remaining 6 cacti and cultivate them in a greenhouse to ensure the population’s survival. Unfortunately, the efforts did not yield the desired results.

The disappearance of the Key Largo tree cactus is disheartening because scientists know this species will not be the last to face such a fate. Countless endemic species are at risk of a similar end.

“Our research in South Florida over the past 25 years shows that more than one in four native plant species are severely threatened by regional extinction or have already been eradicated due to habitat loss, overharvesting, invasive species, and other degradation factors. More than 50 species have already disappeared, including four global extinctions,” commented a researcher.

It is important to note that Florida is a hotspot for cactus diversity in the U.S. The state is home to 8 recognized species, 3 of which are endemic to the Keys.

“We have tentative plans with the Florida Department of Environmental Protection to replant some in the wild,” says Jennifer Possley, regional conservation director at the Fairchild Tropical Botanic Garden.

Rethinking conservation strategies

The extinction of the Key Largo cactus highlights the urgent need to rethink conservation strategies for vulnerable species. The effects of climate change do not announce themselves but arrive unpredictably and chaotically. It is up to us to address them adequately.

Source: Journal of the Botanical Research Institute of Texas