Factors affecting the longevity of earthworms stored in peat.
The weight loss of the dung worm, Eisenia fetida, stored in a variety of peats ranging in pH from 3.6 to 7.2 was compared. Worms in acid peats of pH 3.6-4.3 lost weight less than in more neutral peats of pH 5.5-7.2. Similar results were obtained with the soil-dwelling species Allolobophora caliginosa. In the acid peats the worms burrowed less, produced less faeces and initially respired less. The results suggested that in the more neutral peats the energy expended in feeding exceeded the amount assimilated so that the worms lost weight rapidly. Activity was inhibited by the most acid peats and the rate of weight loss was reduced. The results are relevant to the length of time for which earthworms may be stored in commercial vermiculture.