Southern hairy-nosed wombats improve soil health and plant growth in South Australia

Dr. Ruth Norris of the University of New England found that the southern hairy-nosed wombat provides vital environmental benefits to the semiarid rangelands of South Australia.

Norris conducted a three-year study to examine how these digging mammals interact with their environment. Her research shows that the wombats improve soil health and ecosystem resilience by creating complex warren systems and circular depressions.

These structures act as collection points for water, seeds, and organic material, which the wombats then bury to replenish nutrient-poor soils. The study also found that the wombats serve as a vector for mycorrhizal fungi, which are essential for plant growth because they provide water and nutrients to plants in exchange for sugars. The data reveals that the presence of wombats significantly changes the landscape.

Norris found that these animals reduce soil compaction by up to 78% and increase water infiltration by up to 295%. These actions help insulate the land against harsh conditions and reduce surface evaporation. Consequently, plant density increased by an average of 168% and vegetation cover rose by up to 140% within the wombats' range. Additionally, the burrows provide critical shelter for various species, including birds, reptiles, and small mammals, especially during droughts.

Despite these benefits, many landholders in South Australia view the wombats as a threat to agriculture and often shoot the animals or bulldoze their homes. While the species is currently listed as a species of least concern, scientists warn that habitat loss and a warming climate could lead to extinction by 2070. Norris argues that the wombats are keystone species and calls for a shift from persecuting the animals to assisting them in maintaining the ecosystem.