🌊 Mimram
eDNA Biodiversity Report Card
14 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 | 10 | 47 |
| Gasterosteus aculeatus (Three-spined Stickleback) | Gasterosteidae | 9 | 44 |
| Barbatula barbatula (Stone Loach) | Nemacheilidae | 8 | 24 |
| Phoxinus phoxinus (Minnow) | Cyprinidae | 3 | 16 |
| Squalius cephalus (Chub) | Cyprinidae | 3 | 4 |
| Leuciscus leuciscus (Dace) | Cyprinidae | 2 | 4 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Baetis rhodani (Large Dark Olive) | Baetidae | 10 | 27 |
| Paraleptophlebia submarginata (Turkey Brown) | Leptophlebiidae | 9 | 18 |
| Baetis vernus (Medium Olive) | Baetidae | 7 | 15 |
| Serratella ignita (Blue Winged Olive) | Ephemerellidae | 6 | 11 |
| Cloeon dipterum (Pond Olive) | Baetidae | 3 | 7 |
| Ephemera danica (The Mayfly) | Ephemeridae | 3 | 3 |
| Baetis scambus (Small Dark Olive) | Baetidae | 2 | 3 |
| Procloeon pennulatum (Large Spurwing) | Baetidae | 1 | 1 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Nemurella pictetii (Pictet's Stonefly) | Nemouridae | 9 | 14 |
| Isoperla grammatica (Yellow Sally) | Perlodidae | 6 | 24 |
| Leuctra fusca (Late Needle Fly) | Leuctridae | 4 | 8 |
| Leuctra digitata (Rolled-winged Stoneflies) | Leuctridae | 3 | 3 |
| Nemoura dubitans (Doubtful Stonefly) | Nemouridae | 1 | 2 |
| Nemoura cinerea (Common Stonefly) | Nemouridae | 1 | 1 |
| Species | Family | Sites | ESVs |
|---|---|---|---|
| Glyphotaelius pellucidus (Northern Caddisflies) | Limnephilidae | 9 | 38 |
| Halesus radiatus (Northern Caddisflies) | Limnephilidae | 7 | 11 |
| Silo nigricornis (Humpless Case-maker Caddisflies) | Goeridae | 6 | 7 |
| Sericostoma personatum (Sericostomatid Caddisflies) | Sericostomatidae | 4 | 10 |
| Leptocerus tineiformis (Long-horned Caddisflies) | Leptoceridae | 4 | 6 |
| Limnephilus marmoratus (Northern Caddisflies) | Limnephilidae | 4 | 5 |
| Rhyacophila dorsalis (Free-living Caddisflies) | Rhyacophilidae | 4 | 4 |
| Potamophylax latipennis (Northern Caddisflies) | Limnephilidae | 3 | 3 |
| Lype reducta (Tube-case Caddisflies) | Psychomyiidae | 3 | 3 |
| Halesus digitatus (Northern Caddisflies) | Limnephilidae | 2 | 3 |
| Hydroptila sparsa (Microcaddisflies) | Hydroptilidae | 1 | 2 |
| Athripsodes albifrons (Long-horned Caddisflies) | Leptoceridae | 1 | 2 |
| Limnephilus extricatus (Northern Caddisflies) | Limnephilidae | 1 | 2 |
| Hydroptila martini (Microcaddisflies) | Hydroptilidae | 1 | 1 |
| Athripsodes cinereus (Long-horned Caddisflies) | Leptoceridae | 1 | 1 |
| Drusus annulatus (Northern Caddisflies) | Limnephilidae | 1 | 1 |
| Limnephilus ignavus (Northern Caddisflies) | Limnephilidae | 1 | 1 |
| Lype phaeopa (Tube-case Caddisflies) | Psychomyiidae | 1 | 1 |
| Site | Location | Species | Genera | EPT Families | Notes |
|---|---|---|---|---|---|
| MM8 | Tewinbury Farm | 292 | 208 | 12 | 🌟 |
| MM10A | Panshanger Div. Chan. 2 | 272 | 205 | 13 | |
| MM9 | Archer’s Green | 263 | 187 | 11 | |
| MM6A | Welwyn Allotments | 242 | 180 | 8 | |
| MM6B | Sherrardswood | 209 | 155 | 7 | |
| MM7 | Digswell Park Road | 204 | 155 | 8 | |
| MM3 | Kimpton Mill (upstream site) | 181 | 135 | 6 | |
| MM5 | Singlers Marsh (S. End) | 176 | 133 | 5 | |
| MM10B | Panshanger (downstream site) | 173 | 130 | 9 | |
| MM4 | Codicote Bottom | 33 | 25 | 2 |
🌟 = Most diverse site on river
The Mimram flows through the Upper Lea (Hertfordshire) catchment, where our eDNA survey sampled 10 sites along its length. Analysis of water samples revealed a rich invertebrate community with 640 distinct genetic sequences (Species) representing 639 identified species and 195 families.
Compared to other chalk streams surveyed, the Mimram shows above average for diversity, ranking #5 of 11 rivers. The river supports 14 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.
640 Species detected across 10 sites — CSV format, opens in Excel
