“Earthworms Downunder”: A survey of the earthworm fauna of urban and agricultural soils in Australia

“Earthworms Downunder” was a national survey of the earthworm fauna of urban and agricultural soils in Australia in which 1450 school children measured earthworm abundance and sent specimens to taxonomists for identification. Abundance varied between habitats with highest numbers found in pastures and orchards (means > 140 m−2) and least in cereal crops (mean < 50 m−2). The most common species were the introduced Aporrectodea caliginosa, A. trapezoides, A. rosea, Lumbricus rubellus (Lumbricidae), Microscolex dubius (Acanthodrilidae), Amynthas rodericensis (Megascolecidae) and Pontoscolex corethrurus (Glossoscolecidae). Spenceriella sp. (Megascolecidae) was the most common native species. Species richness was least in soils used for cereal cropping and greatest in urban gardens. Some introduced species (e.g. A. trapezoides and A. caliginosa) were widespread across southern Australia, but rarely found in the northern tropics, whilst other species had the opposite distribution (e.g. P. corethrurus). Closest associations between species were recorded for A. caliginosa, A. trapezoides and L. rubellus.