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We intend to carry out biological tests at this site on a regular basis to monitor the long term effects that water quality has on invertebrate life in the stream.
August 2007
The scores for this sample indicate that the water quality rating is of fair biological quality and the ASPT falls just within the very good rating. Surprisingly no caseless caddis or blackfly larvae were found.
| Location |
Longford Stream – 60 metres below Longford Bridge, Spithurst. |
| Date |
27th August 2007 |
| Grid Reference |
TQ433181 |
| Notes |
Three minute kick sample in pool upstream of bridge. Clay substrate – low flow – heavily shaded. |
| Also netted in this sample. |
Several empty planorbis shells. |
| Biological quality rating |
C. Fair biological quality |
| Water quality rating |
Good |
| Species |
Group |
BMWP Score |
| Leptophlebiidae |
Mayfly nymph |
10 |
| Sericostomatidae |
Cased Caddis Fly |
10 |
| Aeshnidae |
Dragonfly nymph |
8 |
| Limnephilidae |
Cased Caddis Fly |
7 |
| Gammaridae |
Shrimp |
6 |
| Ancylidae |
River limpet |
6 |
| Corixidae |
Water boatman |
5 |
| Dytiscidae |
Diving Beetle |
5 |
| Baetidae |
Mayfly |
4 |
| Sialidae |
Alderfly nymphs |
4 |
| Sphaeriidae |
Pea mussels |
3 |
| Hydrobiidae |
Snail |
3 |
| Glossiphoniidae |
Leech |
3 |
| Asellus |
Hoglouse |
3 |
| Erpobdellidae |
Leech |
3 |
| Chironomidae |
Midge larvae |
2 |
| Oligochaetae |
Tubifex worms |
1 |
| Total Score |
83 |
| ASPT (Average Score Per Taxon) |
4.9 |
May 2006
This is a surprisingly high BMWP score and ASPTfor this location, considering the recent poor water quality result. In April we measured a very high level of ammonia at 1.36 mg/l
which exceeds the EU Freshwater Fisheries Directive Mandatory value of 0.78 mg/l as N.
| Location |
Longford Stream – 60 metres below Longford Bridge, Spithurst. |
| Date |
1st May 2006 |
| Grid Reference |
TQ433181 |
| Notes |
Fast flow, silty substrate, light shading. |
| Also netted in this sample. |
- |
| Biological quality rating |
C. Fair biological quality |
| Water quality rating |
Very good |
| Species |
Group |
BMWP Score |
| Leptophlebiidae |
Mayfly
(Habrophlebia fusca ) |
10 |
| Ephemerellidae |
Mayfly (Ephemerella ignita ) |
10 |
| Ephemeridae |
Mayfly (Ephemera danica) |
10 |
| Lepidostomatidae |
Caddis Fly |
10 |
| Psychomyiidae |
Caddis Fly |
8 |
| Polycentropidae |
Caddis Fly |
7 |
| Gammaridae |
Shrimp |
6 |
| Hydropsychidae |
Caddis Fly |
5 |
| Elminthidae |
Beetle |
5 |
| Simuliidae |
Blackfly |
5 |
| Baetidae |
Mayfly |
4 |
| Piscicolidae |
Fish Leech |
4 |
| Glossiphoniidae |
Leech (Glossiphonia complanata) |
3 |
| Planorbiidae |
Ramshorn Snail |
3 |
| Asellidae |
Hoglouse |
3 |
| Oligochaeta |
Blood worm |
1 |
| Total Score |
94 |
| ASPT (Average Score
Per Taxon) |
5.9 |
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