A CROSS SECTIONAL STUDY OF THE MORPHOLOGY AND ABUNDANCE OF LANISTES LYBICUS AND ASSOCIATED LIMNOLOGICAL FACTORS IN SHEMA DAM , DUTSINMA

This study presents a cross-sectional analysis of the morphology and abundance of Lanistes lybicus, a freshwater gastropod, and its relationship with key limnological factors in Shema Dam, Dutsinma, Katsina State, Nigeria. The research aimed to examine the spatial and temporal distribution of L. lybicus in the dam and investigate how limnological parameters, including water temperature, pH, dissolved oxygen, turbidity, and nutrient concentrations, influenced its population dynamics. Data were collected through weekly sampling of water parameters and snail populations across different locations in the dam over a 3 month period. The results indicated that L. Lybicus populations were most abundant in areas with stable water temperature and moderate turbidity. Positive correlations were observed between snail abundance and dissolved oxygen levels, while pH and nutrient concentrations showed minimal impact. Spatial variation in L. lybicus density was also noted, with higher densities found in shallow, less disturbed zones of the dam. The research found that L. lybicus was more abundant in areas with stable temperatures, moderate turbidity, and high dissolved oxygen levels, with minimal influence from pH and nutrient levels. Morphometric analysis (n = 112) revealed that most snails had shell lengths between 1.6–2.4 mm (65.18%), shell heights between 0.2–1.0 mm (65.18%), and shell widths between 0.3–1.1 mm (66.07%). Mean shell length was 1.65±0.37 mm, and the shell length-to-height ratio (SL/SH) averaged 2.06±1.33. Water conditions averaged 24.4±0.32°C in temperature, 6.8±2.3 pH, and 155.5±32.48 mg/L in total dissolved solids. The study suggests that L. lybicus could serve as a bioindicator for ecosystem health in freshwater environments like Shema Dam.