Effect of Dung-Beetles (Aphodius spp.) and Earthworms on the Disappearance of Cattle Dung

Abstract

The disappearance of cattle droppings, deposited about 1 August, was followed in 1974, 1975 and 1977. Pats covered during the first 5-7 nights (to exclude night-flying beetles, notably Aphodius rufipes (L.)) were compared with freely exposed controls. The night-covering considerably depressed rates of decay, 75% disappearance times for covered pats and controls being 54 and 32 d (74), and 64 and 42 d (77), respectively. In the hot and dry summer of 1975 (without earthworm activity in the surface soil) only 35% of the dung, in both types of pats, disappeared in two months. Hence, disappearance rates were strongly affected by climate. Results suggest that earthworms (particularly Allolobophora longa Ude) accounted for about 50% of the dung disappearance in 1974 and 1977; directly by ingestion and removal, and indirectly e.g. by attacking the crust which protected pats against weathering. Larvae of A. rufipes were responsible for the loss of 14-20%. Apparently, the activity of adult Aphodius and their larvae accelerated the aggregation of worms under pats, thereby promoting rapid disappearance of the dung.