Table 2.
Prevalence of the larval trematodes (% infected snails in the pooled samples) in the two hosts studied in the four Ruhr reservoirs and significance of differences (p) for between-reservoir comparisons (contrasts in overall prevalence and the prevalence of the dominant species).
| Radix auricularia | Lymnaea stagnalis | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Trematode species | Final hosts | Baldeneysee | Hengsteysee | Harkortsee | Kemnader See | p | Baldeneysee | Hengsteysee | Harkortsee | Kemnader See | p |
| Diplostomum spathaceum* | GUL | 0.59 | 5.64 (1) | - | 4.55 | 0.027 | - | - | - | - | - |
| Trichobilharzia franki* | ANA | 0.59 | 8.72 (2) | - | - | 0.0001 | - | - | - | - | - |
| Paryphostomum radiatum* | COR | 3.55 (1) | 4.10 (1) | - | - | ns | - | - | - | - | - |
| Echinoparyphium recurvatum* | ANA | 11.24 (3) | 4.10 (1) | - | - | 0.007 | 1.48 | - | - | - | - |
| Opisthioglyphe ranae* | AM | 1.18 (1) | - | - | 2.27 | ns | - | - | - | 6.25 | - |
| Plagiorchis elegans | VAR | - | 0.51 | 4.55 | - | - | 0.74 | - | - | - | - |
| Australapatemon burti | ANA | - | 1.03 | - | - | - | - | - | - | - | - |
| Echinostomasp. | ANA | 0.59 | 1.54 | - | - | - | - | - | - | - | - |
| Hypoderaeum conoideum | ANA | - | 1.03 | - | - | - | - | - | - | - | - |
| Isthmiophora melis | MAM | - | 1.03 | - | - | - | - | - | - | - | - |
| Notocotylus attenuatus | ANA | 0.59 | 0.51 | - | - | - | - | - | - | - | - |
| Tylodelphys clavata | GRE | - | 1.03 | - | - | - | - | - | - | - | - |
| Diplostomum pseudospathaceum* | GUL | - | - | - | - | - | 3.70 | 9.10 | 17.39 (1) | 12.50 | 0.036 |
| Echinostoma revolutum | ANA | - | - | - | - | - | 5.19 | - | 4.35 | - | - |
| Trichobilharzia szidati | ANA | - | - | - | - | - | 2.96 | - | - | - | - |
| Overall prevalence (%) | 18.3 | 28.2a | 4.6 | 4.6b | 0.0001 | 14.1 | 9.1 | 21.7 | 18.8 | ns | |
| No. of species in component communities (range) | 1-4 | 1-7 | 1 | - | - | 1-2 | - | 2 | - | - | |
| No. of dominant species in component communities (range) | 0-2 | 0-3 | - | - | - | - | - | 1 | - | - | |
Dominant species are indicated by an asterisk and the number of communities where dominant given in parentheses following the overall prevalence. Abbreviations for the definitive host groups of trematodes: AM, amphibians; ANA, anatids; COR, cormorants; GRE, grebes; GUL, gulls; MAM, small mammals; VAR, various lariform and passeriform birds.
atwo double infections; bone double infection.