Effects of population density on the growth and egg-laying capacity of the African giant land snail.

Abstract

The effects of the population density of adult African giant land snail, Archachatina marginata on the egg-laying capacity and the growth of the brooders and hatchlings were investigated for 9 months. Ten culture pens were stocked with snails at 20%, 40%, 60%, 80% and 100% capacity with each group in 2 replicates. Average weight gain of brooders was highest in pens stocked at 40% population density while the lowest was in pen stocked at 100%. Average number of eggs laid per snail and average number of eggs per pen followed the same trend in the study. The highest average number of eggs laid per pen was obtained in pens stocked at 60% population density (586) while the least was from pens at 20% population density. The result was same for average number of eggs laid per snail i.e. 7.5 eggs in pens stocked at 60% and 4.1 eggs in pens stocked at 20%. There was no significant difference in the weights of hatchlings in the different pens.

Keywords: African giant land snail, population density, egg laying capacity, captivity.