Digging mammal reintroductions reduce termite biomass and alter assemblage composition along an aridity gradient

Area of Science:

• Ecology
• Conservation Biology
• Zoology

Background:

• Invasive predators (cats, foxes) caused extinctions and declines of Australian mammals.
• The ecological consequences for soil invertebrates are largely unknown.
• Loss of native mammals as predators and soil disturbance agents may impact invertebrate communities.

Purpose of the Study:

• To test if mammal reintroduction alters vegetation and termite assemblages.
• To investigate if the impact of reintroduction varies with aridity.
• To understand ecological cascades following invasive species.

Main Methods:

• Compared paired sites inside and outside reintroduction sanctuaries across an aridity gradient.
• Sampled termite assemblages using soil trenches.
• Measured vegetation cover and habitat availability.

Main Results:

• Mammal reintroductions led to increased bare ground and reduced vegetation.
• Termite abundance and biomass were lower in reintroduction sites.
• The impact of reintroduction on termites decreased with increasing aridity.
• Soil-nesting wood-feeding termites were most affected.

Conclusions:

• Ecological cascades from invasive predators likely increased termite biomass and altered assemblages.
• Mammal reintroductions can restore some ecosystem functions.
• Impacts are modulated by aridity, suggesting lower effects in less productive habitats.