Melanoides tuberculata in East Africa: Investigating the role of Biotic and Abiotic factors in its presence or absence

Abstract

BackgroundMelanoides tuberculata is one of the most highly invasive snails in the world with strong colonizing capabilities. Its competitive advantage over other freshwater snails has led to its use to biologically control snails that act as intermediate hosts of Schistosoma mansoni, averting the spread of schistosomiasis (a Neglected Tropical Disease infecting approximately 40 million people in East Africa). In East Africa, few studies have been conducted to better understand the biotic and abiotic factors that promote the survival and dominance of M. tuberculata snails. This study purposed to investigate the role of temperature, soil pH, water-depth, water-velocity, soil type, vegetation cover and the presence or absence of other snails on the presence or abscence of M. tuberculata snails from locations across East Africa. ResultsWater depth (p=0.001) was found to be the most statistically significant factor affecting the presence of M. tuberculata snails at the East African sites; the average water-depth where M. tuberculata snails were found was 20.7cm. The presence or absence of other snails was also found to have a statistically significant role on the presence of M. tuberculata snails (p=0.005), with M. tuberculata being rarely found alongside other snails. Water temperature also had a statistically significant role on the presence of M. tuberculata snails (p=0.014); the average water temperature where M. tuberculata snails ere found was 20.27{degrees}C. Vegetation cover (p=0.236), pH (p=0.434), water-velocity (p=0.736) and soil type (p=0.356) potentially had a role on the presence or absence of East African M. tuberculata snails but their effect was not found to be statistically significant. All 7 locations where M. tuberculata snails were found had vegetation cover, an average pH of 8.07, an average water-velocity of 0.49m/s and silt and sandy soil as the soil type. ConclusionIn conclusion, we found that water depth, water temperature and the presence or absence of other snails had a significant role on the presence of M. tuberculata snails in East Africa. Our study provides detailed information on the role of biotic and abiotic factors on the presence of M. tuberculata snails in several locations of East Africa.