Table 2 Estimation of the age of B. senegalensis and B. umbilicatus collected in July 2012 and July 2013 measured and grouped by shell size (mm)
Shell size groups (mm) | Group 1 | Group 2 | Group 3 | Group 4 | ||
|---|---|---|---|---|---|---|
(3–4.9) | (5–6.9) | (7–9.9) | (10–15) | |||
Snail species | Total snails collected | No. Snails (%) | No. Snails (%) | No. Snails (%) | No. Snails (%) | Years |
B. senegalensis | 203 | 0 (0) | 37 (18.2) | 141 (69.4) | 25 (12.3) | 2012 |
B. umbilicatus | 58 | 0 (0) | 21 (36.2) | 32 (55.2) | 5 (8.6) | |
B. senegalensis | 421 | 0 (0) | 90 (21.4) | 256 (60.8) | 75 (17.8) | 2013 |
B. umbilicatus | 108 | 0 (0) | 27 (25) | 72 (66.7) | 9 (8.3) | |
B. senegalensis | 624 | 0 (0) | 127 (20.3) | 397 (63.6) | 100 (16.1) | All years |
B. umbilicatus | 166 | 0 (0) | 48 (30) | 104 (62.6) | 14 (8.4) |