📍 U7: Mill Green

River: Lea Catchment: Upper Lea (Hertfordshire) Filter(s): 349

Your Site at a Glance

305
Species Detected
214
Genera Identified
105
Families Found
708,900
DNA Sequences

How Your Site Compares

Metric Your Site Lea Average Study Average
Species 305 251 206
Genera 214 174 151
Families 105 87 83
EPT Families 6 6 6

Rank 1 of 10 on Lea Rank 5 of 81 in study

🌊 Water Quality Indicators

Good

BMWP score: 84 (Good) — ASPT score: 5.6 (Good)

15 scoring macroinvertebrate families detected

Clean water with slight impacts; a healthy community of macroinvertebrate families is present.

🔍 Notable Findings

Conservation Species:

Invasive Species:

🦋 Top 10 Families at Your Site

1. Chironomidae (Non-biting Midges)
75 (24.6%)
2. Naididae (Aquatic Oligochaetes)
30 (9.8%)
3. Cyprinidae (Carp and Allies)
13 (4.3%)
4. Lumbricidae (Common Earthworms)
8 (2.6%)
5. Psychodidae (Moth Flies)
7 (2.3%)
6. Simuliidae (Black Flies)
6 (2.0%)
7. Staphylinidae (Rove Beetles)
5 (1.6%)
8. Lumbriculidae (Aquatic Earthworms)
5 (1.6%)
9. Enchytraeidae (Potworms)
5 (1.6%)
10. Anatidae (Ducks, Geese, and Swans)
5 (1.6%)
Taxonomic composition

🪲 Extended Riverfly Taxa

1 Flatworms ✗ 18Dragonflies and Damselflies✗
2 Freshwater Snails ✓ 19Water Boatmen✗
3 Limpets ✗ 20Other Water Bugs✓
4 Bivalves ✓ 21Water Beetles✓
5 Aquatic Worms ✓ 22Alderflies✗
6 Leeches ✗ 23Caseless Caddisflies - Green Sedge✗
7 Crayfish ✓ 24Caseless Caddisflies - Net Spinners✗
8 Water Hoglouse ✓ 25Caseless Caddisflies - Non-Gilled✓
9 Freshwater Shrimps ✓ 26Cased Caddisflies - Hood Case-Maker✗
10 Invasive Non-Native Shrimps ✗ 27Cased Caddisflies - Weighted Case-Maker✓
11 Mayflies - Angler's Curse ✓ 28Cased Caddisflies - Bush Tailed Caddisfly✗
12 Mayflies - Olives ✓ 29Cased Caddisflies - Other✓
13 Mayflies - Prong Gilled ✗ 30Craneflies✓
14 Mayflies - Flatbodied ✗ 31Blackflies✓
15 Mayflies - Green Drake ✗ 32Non-Biting Midges✓
16 Mayflies - Blue-Winged Olive ✓ 33Water Snipe Flies✗
17 Stoneflies ✗
17/33 Extended Riverfly taxa detected

Note: The Extended Riverfly Monitoring Initiative calculates scores based on abundance categories, which cannot be determined from eDNA presence/absence data. This checklist shows which taxa groups were detected but does not constitute an official ARMI score.

🐟 Fish Species

16 fish species detected (4 families, 103 ESVs)
SpeciesFamilyESVs
Gobio gobio (Gudgeon) Cyprinidae 11
Leuciscus leuciscus (Dace) Cyprinidae 9
Squalius cephalus (Chub) Cyprinidae 8
Phoxinus phoxinus (Minnow) Cyprinidae 7
Barbus barbus (Barbel) Cyprinidae 4
Rutilus frisii Cyprinidae 4
Cottus bairdii Cottidae 4
Gobio kovatschevi Cyprinidae 3
Gasterosteus aculeatus (Three-spined Stickleback) Gasterosteidae 3
Scardinius acarnanicus Cyprinidae 3
Cyprinus carpio (Common Carp) Cyprinidae 2
Barbatula barbatula (Stone Loach) Nemacheilidae 2
Luciobarbus bocagei Cyprinidae 1
Gobio muresius Cyprinidae 1
Rutilus rubilio Cyprinidae 1

🪰 EPT Species (Mayflies, Stoneflies & Caddisflies)

10 EPT species detected (6 families, 23 ESVs — E:5 / P:0 / T:5)
SpeciesFamilyESVs
Ephemeroptera (Mayflies)
Baetis rhodani (Large Dark Olive) Baetidae 3
Caenis luctuosa (Angler's Curse) Caenidae 2
Baetis vernus (Medium Olive) Baetidae 1
Cloeon dipterum (Pond Olive) Baetidae 1
Serratella ignita (Blue Winged Olive) Ephemerellidae 1
Trichoptera (Caddisflies)
Glyphotaelius pellucidus (Northern Caddisflies) Limnephilidae 10
Limnephilus extricatus (Northern Caddisflies) Limnephilidae 2
Crunoecia irrorata (Lepidostomatid Caddisflies) Lepidostomatidae 1
Limnephilus marmoratus (Northern Caddisflies) Limnephilidae 1
Lype phaeopa (Tube-case Caddisflies) Psychomyiidae 1

🔗 Your Ecological Twin

Most similar site: U6 - Stanborough South
River: Lea (same river)
Similarity: 53% of species shared
Download Data

305 Species detected at this site — CSV format, opens in Excel

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