Table 1. Mean densities ± SE (per site) and occurrences of anopheline larvae sampled from the water hyacinths that were surrounded by trees or other tall emergent plants, or that were exposed to waves in the lake in 2008 and 2009.
| Taxa | Trees (n = 36) | Non-woody tall plants (n = 71) | Short plants (exposed) (n = 44) | 2008 (n = 93) | 2009 (n = 58) | Total (n = 151) | No. of larvae (%) (n = 1047) |
| An. funestus s.s.* | 2.4±0.8 (13)a | 0.0±0.0 (0)b | 0.1±0.1 (2)b | 0.8±0.3 (11) | 0.3±0.2 (4) | 0.6±0.1 (15) | 91 (8.7) |
| An. lessoni | 0.1±0.1 (3) | 0 (0) | 0 (0) | <0.1 (2) | <0.1 (1) | <0.1 (3) | 3 (0.3) |
| An. rivulorum * | 3.5±1.1a (14) | 0.8±0.5b (12) | 0.3±0.2b (4) | 1.3±0.4 (22) | 1.3±0.7 (8) | 1.3±0.4 (30) | 195 (18.6) |
| An. arabiensis | 0.7±0.6 (4) | 0.1±0.0 (3) | 0.2±0.2 (2) | 0.1±0.0 (4) | 0.6±0.4 (5) | 0.3±0.1 (9) | 38 (3.6) |
| An. gambiae s.s. | 0 (0) | 0 (0) | 0.1±0.1 (2) | <0.1 (1) | <0.1 (1) | <0.1 (2) | 3 (0.3) |
| An. pharoensis | 0 (0) | 0.2±0.2 (3) | 0.1±0.0 (2) | 0.1±0.1 (1) | 0.3±0.2 (4) | 0.1±0.1 (5) | 20 (1.9) |
| An. coustani s.l. | 6.2±1.4 (24) | 3.8±0.8 (38) | 4.6±1.4 (18) | 5.1±0.8 (59) | 3.9±1.2 (20) | 4.6±0.6 (79) | 697 (66.6) |
The numbers in parentheses after the density value indicate positive sites. The values with the same letter were not statistically significant (P>0.05). Where letters are missing on densities, the count portion was excluded from the optimal zero-inflated regression model or hurdle model. Similarly, the binomial portion was excluded where letters are missing on the numbers of positive sites.
*
Species included in the analyses.