Melting Glaciers Provide Fertile Ground for Invasive Species

Invasive species spread through human activities are one of the main causes of the ongoing biodiversity crisis.

Even on South Georgia, a remote island located in the very south of the Atlantic Ocean, exotic species are present. Many of which were inadvertently introduced by whalers and sealers in the 19th and early 20th century.

In a new study published in the open-access journal Neobiota and funded by Darwin Plus, researchers explored how living organisms colonise new ground provided by melting glaciers.

Like other cold regions of the world, South Georgia is losing its glaciers because of climate change, leaving behind large areas of newly uncovered bare ground.

Researchers surveyed the foreland biodiversity of six glaciers, creating an inventory of the flora and fauna that colonise forelands at different stages of glacial retreat.

They found that, just a few years after bare ground is exposed by a glacier melting, pioneer plants arrive, progressively covering more ground with time, followed by an increasing number of species.

Native and exotic plants, as well as invertebrates, take advantage of this opportunity. Surprisingly, two temperate plant species from the Northern Hemisphere, annual meadow grass and mouse-ear chickweed, colonise sites faster than any other species.

The team suggests their results indicate invasive species will likely spread on South Georgia as fast as glaciers are retreating. Whether this has or will have negative consequences on local species needs to be investigated to help protect this unique ecosystem.

Reference: Tichit P, Brickle P, Newton RJ, Convey P, Dawson W. Introduced species infiltrate recent stages of succession after glacial retreat on sub-Antarctic South Georgia. NeoBiota. 2024;92:85-110. doi: 10.3897/neobiota.92.117226

This article has been republished from the following materials. Note: material may have been edited for length and content. For further information, please contact the cited source.