🌊 Ewelme Brook
eDNA Biodiversity Report Card
13 EPT families
Outstanding diversity of pollution-sensitive invertebrates indicating pristine water quality.
Top 15 families detected by eDNA analysis:
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Salmo trutta (Brown Trout / Sea Trout) | Salmonidae | 5 | 16 |
| Phoxinus phoxinus (Minnow) | Cyprinidae | 4 | 8 |
| Squalius cephalus (Chub) | Cyprinidae | 3 | 6 |
| Gasterosteus aculeatus (Three-spined Stickleback) | Gasterosteidae | 3 | 6 |
| Barbatula barbatula (Stone Loach) | Nemacheilidae | 2 | 3 |
| Gobio gobio (Gudgeon) | Cyprinidae | 1 | 2 |
| Leuciscus leuciscus (Dace) | Cyprinidae | 1 | 1 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Baetis rhodani (Large Dark Olive) | Baetidae | 6 | 20 |
| Serratella ignita (Blue Winged Olive) | Ephemerellidae | 3 | 6 |
| Paraleptophlebia submarginata (Turkey Brown) | Leptophlebiidae | 2 | 4 |
| Cloeon dipterum (Pond Olive) | Baetidae | 1 | 3 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Nemurella pictetii (Pictet's Stonefly) | Nemouridae | 2 | 2 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Drusus annulatus (Northern Caddisflies) | Limnephilidae | 5 | 6 |
| Sericostoma personatum (Sericostomatid Caddisflies) | Sericostomatidae | 4 | 10 |
| Limnephilus extricatus (Northern Caddisflies) | Limnephilidae | 3 | 8 |
| Apatania cimbrica (Apataniid Caddisflies) | Apataniidae | 3 | 4 |
| Silo nigricornis (Humpless Case-maker Caddisflies) | Goeridae | 2 | 3 |
| Rhyacophila dorsalis (Free-living Caddisflies) | Rhyacophilidae | 2 | 3 |
| Agapetus fuscipes (Saddle-case Makers) | Glossosomatidae | 2 | 2 |
| Crunoecia irrorata (Lepidostomatid Caddisflies) | Lepidostomatidae | 2 | 2 |
| Limnephilus marmoratus (Northern Caddisflies) | Limnephilidae | 2 | 2 |
| Lype reducta (Tube-case Caddisflies) | Psychomyiidae | 2 | 2 |
| Leptocerus tineiformis (Long-horned Caddisflies) | Leptoceridae | 1 | 2 |
| Silo pallipes (Humpless Case-maker Caddisflies) | Goeridae | 1 | 1 |
| Chaetopteryx villosa (Northern Caddisflies) | Limnephilidae | 1 | 1 |
| Glyphotaelius pellucidus (Northern Caddisflies) | Limnephilidae | 1 | 1 |
| Site | Location | Species | Genera | EPT Families | Notes |
|---|---|---|---|---|---|
| E6 | Brook Street | 264 | 201 | 8 | 🌟 |
| E5 | Braze Lane | 243 | 185 | 11 | |
| E3 | Ewelme Mill | 228 | 166 | 6 | |
| E7 | Millbrook Mead (downstream sit... | 124 | 99 | 1 | |
| E2 | Watercress Centre | 115 | 90 | 6 | |
| E1A | King's Pool: Ewelme (upstream ... | 67 | 58 | 4 |
🌟 = Most diverse site on river
The Ewelme Brook flows through the Thames & Chilterns South catchment, where our eDNA survey sampled 7 sites along its length. Analysis of water samples revealed a rich invertebrate community with 451 distinct genetic sequences (Species) representing 450 identified species and 175 families.
Compared to other chalk streams surveyed, the Ewelme Brook shows moderate diversity compared to other rivers in the study (#8 of 11). The river supports 13 families of mayflies, stoneflies, and caddisflies (EPT) - key indicators of water quality.
Notable findings include the detection of conservation priority species (Water vole, Water shrew) and invasive species requiring management attention.
451 Species detected across 7 sites — CSV format, opens in Excel
