GROWTH AND REPRODUCTION OF EISENIA-ANDREI AND EISENIA-FETIDA (OLIGOCHAETA, LUMBRICIDAE) IN DIFFERENT ORGANIC RESIDUES

A comparative study of E. andrei and E. fetida growing in different or ganic residues was carried out to determine whether the population dyn amics are substantially different in these two taxonomically close rel ated species. Growth rates in three of the four different residues tes ted (paper pulp mill sludge, domestic refuse, cow manure and rabbit ma nure) were similar. E. andrei needed less time for clitellum developme nt and cocoon production than E. fetida and this provides an important competitive advantage in F1 recruitment for the latter species. Cocoo n size, hatch period and number of hatchlings per cocoon were slightly in E. fetida. When both species were bred together, no negative effec ts on growth and reproduction were detected.