A newly identified species of fungus, dubbed the ‘moss die-back fungus’, has emerged as a potential ally in the battle against the invasive heath-star moss, which has wreaked havoc on native ecosystems across the UK. This remarkable discovery offers a glimmer of hope for restoring habitats that have suffered due to the aggressive spread of non-native species.
The Discovery of a Unique Fungus
Dr George Greiff, a researcher at Amgueddfa Cymru museum in Cardiff, made this groundbreaking discovery while exploring the Isle of Wight four years ago. Initially puzzled by the sight of dead heath-star moss on a cliffside, he collected samples for further analysis. Over time, he observed an alarming increase in instances of decaying moss. Collaborating with fellow scientists in both the UK and France, Greiff eventually identified the culprit—the moss die-back fungus, a potent organism never before documented.
“This fungus challenges our conventional perception of fungi as harmful,” Greiff remarked. “In this case, it acts as a beneficial agent, targeting the heath-star moss that has proliferated throughout Britain.”
The Invasive Heath-Star Moss
The heath-star moss, an ornamental plant that can thrive in various environments—from hillsides to sand dunes—has gained notoriety for its invasive nature. Greiff noted, “It’s aggressive. I’ve even seen it growing in tarmac.” Since its introduction to the UK in the 1940s, it has spread rapidly, displacing native moss species and disrupting local ecosystems. By the early 1990s, the heath-star moss was ubiquitous, leading to a significant decline in local biodiversity.
In Britain, invasive species are a growing concern, with around 2,000 non-native plants and animals having been introduced, often leading to ecological imbalance. The grey squirrel, a well-known invasive species, has decimated native red squirrel populations, while other plants like Japanese knotweed have caused substantial damage to infrastructure.
The Role of the Moss Die-Back Fungus
Greiff’s research indicates that the moss die-back fungus specifically targets the heath-star moss, creating what he refers to as “fairy rings of death.” During a recent excursion in Bannau Brycheiniog national park, Greiff explained the significance of his findings. “In heathlands like this one, native mosses have either locally gone extinct or dramatically decreased in numbers. The fungus allows native flora, such as baby heather plants, to thrive in spaces previously occupied by the invasive moss.”
The fungus’s mechanism of action involves penetrating the moss cells and causing decay, which, while alarming on the surface, appears to selectively affect only the heath-star moss and potentially one other moss species. This specificity highlights the potential of the fungus as a natural biological control agent, a rare instance of the British ecosystem pushing back against invasive species.
A Promising Future for Conservation
Dr Nathan Smith, Head of Plant and Earth Science at the Amgueddfa Cymru museum, emphasised the importance of this discovery. “This fungus presents an opportunity to preserve unique moss landscapes that serve as habitats for various insects, fungi, and other plants. It provides a genuine chance to protect and showcase their distinctiveness and beauty.”
As biodiversity faces unprecedented threats, with one in six species at risk of extinction, the identification of a natural solution to combat habitat loss is not only timely but critical. Greiff expressed his enthusiasm for the discovery, stating, “It’s exciting in many respects, though I am currently the only one actively searching for the fungus. It would be encouraging to see more researchers joining in.”
Why it Matters
The emergence of the moss die-back fungus as a natural control for the invasive heath-star moss represents a significant step forward in conservation efforts within the UK. This discovery highlights the intricate interdependencies within ecosystems and underscores the potential for native species to reclaim their habitats. As invasive species continue to threaten biodiversity, finding sustainable solutions like this fungus may prove essential in safeguarding the future of Britain’s unique flora and fauna.
