Earthworm Projects

Projects

References

Contacts

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My main interest has always been in the deep digging black-headed earthworm.

A trial in the North West has shown that A. longa can be bred quite simply, and in very large numbers. A small area of paddock (15 x 5 m) was initially sown with lime at an equivalent of 1t/ha and then regularly covered with hay/straw (both to feed the worm and to discourage grass growth which complicates harvesting the worm). Occasionally, coffee grounds have also been spread on the area.
Various methods of forcing earthworms to the surface for identification/collection have been trialled, including;
1. The use of mustard powder
2. The ‘worm grunting’ method utilising a hardwood stake driven into the soil with a flat iron rubbed to cause the stake to vibrate
3. The use of electric current (from a generator)
None of the methods were effective, but perhaps the electric current needs to be used on soils with a high mineral contant as it is an effective method in the collection of native earthworms on the West coast.
To verify observations of A. longa in a wide variety of habitats, 10 samples were collected from 5 diverse locations (including a paddock with clay loam soil, an industrial rehabilitation site, under pasture alongside sand dunes (20m in from high tide mark), from a chook yard alongside pasture and from a heavy clay soil. All 10 samples were affirmed by dna analysis.
Surveys;
1. Regional surveys in the North of the State suggest that the species may have been intentionally introduced into Tasmania by staff of the Van Diemen’s Land Company over 150 years ago.
2. Various farm surveys have been undertaken of A. longa. The main item of interest resulting from a survey of the Dairy Research Centre at Elliott was the absence of the species in paddocks that have been irrigated for over 5 years; the lack of the species is possibly due to a combination of both the irrigation (amounting to a doubling of the typical annual rainfall) and associated high stocking rates leading to soil compaction.
3. Currently surveys are being undertaken to determine the presence of A. longa in the South.
L terrestris could be collected and bred (perhaps in a nursery similar to the one for A. longa), and introduced into agricultural areas.