Summary
Macroinvertebrate surveys of outflows from Bishop’s Sutton, above and below settlement ponds at Drayton Farm and Manor Farm watercress farms at Alresford, Hampshire were carried out using standard sampling techniques The purpose was to repeat surveys undertaken in the autumn of 2019 through 2021 in order to investigate any changes and identify any potential water quality issues
The species present were typical of a chalk stream, with good diversity and water quality scores. A complete list of species is presented together with abundance and diversity (WHPT) scores. The indices showed a variety of responses from the previous year across sites with the most significant change being a decline at Bishops Sutton. Manor Farm showed an increase and the Drayton sites showed a very minor decline. All the results were within normal year to year variation shown by each site.
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The purpose of this survey was to repeat the assessments carried out in previous years of the discharges from the watercress beds at Bishop’s Sutton, Drayton and Manor Farm around Alresford and identify any impacts to biodiversity. The protocols followed were identical to those used previously and as such, this report follows the format of the previous report (Aquilina, 2021). Much of the descriptive material is retained from that report in order to facilitate understanding.
Drayton and Manor Farm are situated at the head of small chalk streams and use borehole water to supply the watercress beds which then is discharged into the stream. Bishop’s Sutton is located slightly further down the headwaters of another stream but is also fed by borehole water.
All three unnamed streams join the River Alre either directly (Manor Farm) or via Old Alresford Pond. The River Alre in turn joins the River Itchen, an important chalk stream for salmon and trout fishing and conservation.
Sampling at Drayton Farm was carried out above and below the main site as per previous sampling.
The Drayton sites were visited by Robert Aquilina on Tuesday 6th September 2022 and Manor Farm and Bishops Sutton on Tuesday 20th September 2021. The dates follow those of the surveys from the previous year.
The weather conditions were dry and suitable for the survey with lower than normal water flow levels at all sites except above Drayton
Industry standard survey and extraction techniques for the stream (Environment Agency 2012) were used to assess the species present.
Methods
The methodology followed is the standard Environment Agency survey and extraction protocol which results in a species list with abundance data. This forms the basis for calculating a number of indices designed to assess the impacts of various factors (depending on the index selected) but in this case is used to calculate the WHPT index (Walley Hawkes Paisley Trigg river invertebrate index that is used as the basis for river invertebrate status classification for Water Framework Directive)
Aquatic macroinvertebrates were collected using a standard size FBA D frame pond net from the major habitats along the stream (stands of different wetland plants, distinctive substrates, tree roots etc.). All the different habitats present were allocated a proportion of the overall sampling time (3 minutes) and different areas of the same mesohabitat were subsampled to ensure that as great a range as possible was sampled.
5 Introduction
Each location was also searched for an additional minute looking for surface dwelling animals such as water skaters and whirligig beetles and inspecting submerged habitats such as logs and larger stones for attached animals.
The samples were preserved in 70% IMS and sorted in the laboratory, where all the invertebrates were extracted and counted. The standard BMWP invertebrate groups were recorded : Tricladida (flatworms), Gastropoda (snails and bivalves), Crustacea (slaters, shrimps and crayfish), Hirudinea (leeches), Megaloptera (alderflies), Plecoptera (stoneflies), Ephemeroptera (mayflies), Odonata (dragonflies and damselflies), Hemiptera (water bugs), Coleoptera (water beetles), Trichoptera (caddisflies) and Diptera (true flies). Voucher specimens were retained in order to check their identity.
Dead mollusc shells, and empty caddis cases were discarded and only whole animals were included in the counts.
BMWP
Condition assessment of running waters is based on the BMWP (Biological Monitoring Working Party) score. These BMWP family scores (1 10) are industry standard and reflect the sensitivity of the families to pollution. The higher the family score, the more sensitive to oxygen depletion the family is and therefore their presence indicates a cleaner or less impacted site. The effects of pollution generally are to impose a Biological Oxygen Demand upon the receiving waters and so sensitive families are progressively excluded as the BOD increases.
The score for each family present is totalled to give a site score. Because these site BMWP scores are influenced by sample size (a high score can be achieved through a large number of low scoring families as well as a small number of high scoring families) an Average Score Per Taxa (ASPT) is also calculated from the resulting BMWP scores and allows further interpretation of the results. The higher the ASPT, the greater the proportion of more sensitive families in the sample and therefore the better the site condition.
WHPT
WHPT better reflects the quality of the invertebrate community because it is based on a wider range of taxa (mostly families). In particular, WHPT includes more families of Diptera and some families that were grouped together in BMWP (known as BMWP composite taxa) are considered separately in WHPT. So 106 taxa are included in WHPT as opposed to the 82 in BMWP.
Additionally the abundance of each taxa is taken into account through the use of abundance classes, the WHPT score for each taxa present depending on its abundance.
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Abundance category Numerical abundance
999
Table 1: WHPT abundance classes
Apart from accounting for abundance, the calculation of scores is the same as for BMWP and results in equivalent but more accurate reflection of water quality. The scores derived are WHPT overall score (equivalent to BMWP), N taxa (number of taxa contributing to the score) and ASPT.
Locations
All locations are as sampled in previous years and are described below with any changes in the habitat noted.
The Bishop’s Sutton outflow is located at SU 60400 32321
The outflow channel is canalised and subject to fast deep flow. There is a gravel bed with some Ranunculus growth but the banks are vertical stone with little vegetation. Therefore mesohabitats were limited to gravel, Ranunculus, marginal vegetation and the Fontinalis moss growing downstream of the weir. The Ranunculus had significantly declined (or been removed) since last year as had the Fontinalis on the weir.
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AB1 1 9 AB2 10 99 AB3 100
AB4 >1000
Photo 1. Bishops Sutton.
The Drayton Farm below settlement ponds outflow was located at SU 59358 33272.
The sample reach was downstream of a bridge with culverts discharging the water, leading to scour in the channel bed. Substrate in this area was gravel with cobbles but was of limited extent. Further downstream, the substrate was fine and soft underfoot in the majority of the channel with some gravel reaches. Banks were earth but had little marginal vegetation. No in channel vegetation was present presumably because of the shade from the trees. Sampling was concentrated in the gravel and cobble area for 2 minutes and then upstream of the bridge for 1 minute in gravel. Water levels were lower than normal and presumably flow rate was also down.
Photo 2. Below Drayton Farm
The Drayton Farm above settlement ponds outflow was located at SU 59682 33310.
The channel is approximately 1 1.5 metres wide and 0.2 0.3 metres deep. Water flow is maintained by discharge from the borehole. The habitats present consisted of gravel, coarse and fine sands, Ranunculus beds and marginal Glyceria maxima with small amounts of other marginal plants. This represents the head of the stream as upstream are the watercress beds and borehole supply.
Ranunculus growth was similar to last year but there was significantly more sand and silt at the expense of gravel. This may have been the result of reduced water flows.
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The Manor Farm outflow is located at SU 58532 33516.
The habitats present consisted of cobbles, small stone, gravel, coarse sand, with significant regrowth of marginal vegetation (Common reed, Watercress and Water Speedwell) similar to last year. Again there was very little in channel Ranunculus.
The channel beyond the tree has become very overgrown with emergent plants and very silted as a result of runoff from the neighbouring site which appears to be undergoing some construction work with heavy vehicles.
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Photo 3. Above Drayton Farm.
Results
The full species lists are presented as an appendix. The results summarised here consist of number of species, abundance and WHPT, N taxa and ASPT for 2019 through to 2022.
All the significant indices are comparable with previous years. The largest change was at Bishops Sutton where all the scores were down on 2021 but still comparable with 2020. This is very likely to be because of vegetation removal which appears to have affected the in channel Ranunculus as well as the Fontinalis on the weir steps.
Above Drayton and Manor Farm were practically the same as in 2021, although the significant increase in sand and silt above Drayton might be expected to have caused a larger decline.
Below Drayton showed an increase compared with previous years.
All of the results are within the normal year on year variation except Bishops Sutton where the decline was caused by significant vegetation removal. This normal variation consists of a mix of sampling as well as weather related and biological factors.
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Photo 4. Manor Farm.
Site Date Season # species Abundance Ntaxa WHPT ASPT
Bishop’s Sutton
3/9/19 Autumn 54 2488 38 201.9 5.31 15/9/20 Autumn 46 3035 32 161.8 5.06 22/9/21 Autumn 57 3252 41 225.4 5.50 20/9/22 Autumn 45 1545 33 165.4 5.01
Drayton Farm below settlement ponds 3/9/19 Autumn 41 918 31 160.8 5.19
7/9/20 Autumn 40 1043 34 175.0 5.15 7/9/21 Autumn 48 866 38 198.2 5.22 6/9/22 Autumn 58 1080 40 214.8 5.37
Drayton Farm above settlement ponds 22/8/18 Summer 46 1966 32 149.4 4.67
3/9/19 Autumn 45 1242 33 165.4 5.01 7/9/20 Autumn 43 1772 35 160.8 4.59 7/9/21 Autumn 43 1281 35 168.2 4.81 6/9/22 Autumn 41 2187 32 156.1 4.88
Manor Farm 3/9/19 Autumn 53 2699 38 211.6 5.57 15/9/20 Autumn 47 4894 35 174.0 4.97 22/9/21 Autumn 54 3332 38 200.8 5.28 20/9/22 Autumn 47 3937 37 190.1 5.14
Values showing an increase are highlighted in blue
Table 2. Results summary
Much of the variation in species richness is contributed by single occurrences of species whereas most of the variation in abundance is due to variation of a small number of species. Gammarus counts are summarised below and show a general increase across the sites which might be weather related, the decrease at Bishops Sutton is assumed to have been caused by vegetation removal.
Site Sept 2019 Sept 2020 Sept 2021 Sept 2022
Bishop’s Sutton 928 1606 1708 728
Drayton below settlement ponds 364 440 139 283
Drayton above settlement ponds 159 580 127 393
Manor Farm 1341 3598 1560 3020
Table 3. Gammarus counts
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The results illustrate the natural variation between years and does not indicate any significant change in water quality. The largest decline at Bishops Sutton is strongly suspected to be related to vegetation removal which can be seen to be significant from the photograph.
WHPT scores
Graph 1. Annual WHPT scores
The relative cover of the habitats present at each site were all similar to the previous year except at Bishops Sutton, although some sedimentation was noticed above Drayton which might be related to lower water flows.
Gammarus counts show a general increase across sites.
Overall it is concluded that the hot and bright summer has not had a significant effect presumably because the water temperature did not increase unduly. One of the significant environmental factors influencing all these sites is the constancy of water from the chalk aquifer including water temperature and chemical constituents. Water quality and macroinvertebrate diversity remain high.
12 Discussion
120 140 160 180 200 220 240
Manor Farm Above Drayton Below Drayton Bishops Sutton
References
Aquilina, R. (2019). Macroinvertebrate Survey of watercress farm outflows, Alresford, Hants.
Aquilina, R. (2021). Macroinvertebrate Survey of watercress farm outflows, Alresford, Autumn, 2021
Clarke,R.T., Furse, M.T., Gunn, R.J.M., Winder, J.M. and Wright, J.F. (2002). Sampling variation in macroinvertebrate data and implications for river quality indices. Freshwater Biology 47, 1735 1751.
Environment Agency. (2012). Freshwater macro invertebrate sampling in rivers. Operational instruction 018_08. Environment Agency.
Environment Agency. (2012). Freshwater macro invertebrate analysis of riverine samples. Operational instruction 024_08. Environment Agency.
Environment Agency. (2014). Walley Hawkes Paisley Trigg (WHPT) index of river invertebrate quality and its use in assesing ecological status. Brief Guide version 5.
Paisley,M.F., Trigg,D.J. and Walley,W.J. (2013). Revision of the Biological Monitoring Working Party (BMWP) score system: derivation of present only and abundance related scores from field data. River Research and Appications. 30: 887 904.
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Group BMWP family Species Common name Status Abundance
Bishops Sutton
Tricladida Dendrocoelidae Dendrocoelum lacteum Flatworm 1
Tricladida Dugesiidae Dugesia polychroa gr. Flatworm 4
Tricladida Planariidae Polycelis felina Flatworm 1
Tricladida Planariidae Polycelis nigra Flatworm 3
Tricladida Planariidae Polycelis tenuis Flatworm 25
Mollusca Hydrobiidae Potamopyrgus antipodarum Jenkins spire snail
Mollusca Physidae Physa fontinalis Bladder snail 9
Mollusca Lymnaeidae Radix balthica Wandering snail =Lymnaea peregra 6
Mollusca Lymnaeidae Stagnicola fuscus Marsh Pond snail
Mollusca Planorbidae Anisus leucostoma Button ramshorn
Mollusca Planorbidae Anisus vortex Whirlpool ramshorn 3
Mollusca Planorbidae Bathyomphalus contortus Twisted ramshorn
Mollusca Planorbidae Gyraulus albus White ramshorn
Mollusca Valvatidae Valvata cristata Flat valve snail
Mollusca Valvatidae Valvata piscinalis Common valve snail
Mollusca Ancylidae Ancylus fluviatilis River limpet 38
Mollusca Sphaeridae Pisidium sp. Pea mussel 2
Crustacea Asellidae Asellus aquaticus Water slater 104
Crustacea Gammaridae Gammarus pulex Freshwater shrimp 728
Hirudinea Erpobdellidae Erpobdella octoculata Leech 9
Hirudinea Erpobdellidae Trocheta subviridis Leech
Hirudinea Glossiphonidae Alboglossiphonia heteroclita Leech 1
Appendix 1 Species recorded with abundance.
Group BMWP family Species Common name Status Abundance
Hirudinea Glossiphonidae Glossiphonia complanata Leech 9
Hirudinea Glossiphonidae Helobdella stagnalis Leech 3
Hirudinea Glossiphonidae Theromyzon tessulatum Duck leech 1
Hirudinea Piscicolidae Piscicola geometra Fish leech 3
Plecoptera Nemouridae Nemurella picteti Stonefly
Plecoptera Leuctridae Leuctra fusca Stonefly
Plecoptera Leuctridae Leuctra nigra Stonefly
Ephemeroptera Ephemerellidae Serratella ignita Blue winged Olive
Ephemeroptera Baetidae Baetis rhodani Large Dark Olive 102
Ephemeroptera Baetidae Baetis vernus Medium Olive 272
Ephemeroptera Caenidae Caenis sp. Mayfly early instars not identifiable to species
Megaloptera Sialidae Sialis lutaria Alderfly
Hemiptera Gerridae Gerris sp. Water skater nymph
Hemiptera Veliidae Velia caprai Water cricket
Hemiptera Corixidae Sigara dorsalis Lesser water boatman
Hemiptera Corixidae Lesser water boatman nymph
Coleoptera Haliplidae Brychius elevatus Crawling water beetle
Coleoptera Haliplidae Haliplus lineatocollis Crawling water beetle 2
Coleoptera Haliplidae Haliplus sp. Crawling water beetle larvae not identifiable to species 3
Coleoptera Dytiscidae Nebrioporus elegans Diving beetle 1
Coleoptera Dytiscidae Oreodytes sanmarkii Diving beetle 5
Coleoptera Dytiscidae Diving beetle larvae not identifiable to species
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Group BMWP family Species
Common name Status Abundance
Coleoptera Hydrophilidae Anacaena globulus Water beetle
Coleoptera Hydrophilidae Laccobius bipunctatus Water beetle
Coleoptera Elmidae Elmis aenea Riffle beetle larva and adults 42
Coleoptera Elmidae Limnius volckmari Riffle beetle larvae 1
Coleoptera Elmidae Riolus subviolaceus Riffle beetle larva and adults 1
Coleoptera Scirtidae Elodes sp. Marsh beetle larva 3
Trichoptera Hydropsychidae Diplectrona felix Caseless caddis 1
Trichoptera Hydropsychidae Hydropsyche siltalai Caseless caddis
Trichoptera Polycentropodidae Plectrocnema conspersa Caseless caddis
Trichoptera Rhyacophilidae Rhyacophila dorsalis Caseless caddis 7
Trichoptera Glossosomatidae Agapetus fuscipes Saddle case caddis 5
Trichoptera Brachycentridae Brachycentrus subnubilis Cased caddis
Trichoptera Hydroptilidae Agraylea multipunctata Cased caddis
Trichoptera Hydroptilidae Hydroptila sp. Cased caddis larvae not identifiable to species 1
Trichoptera Hydroptilidae Oxyethira sp. Cased caddis larvae not identifiable to species 10
Trichoptera Beraeidae Beraeodes minutus Cased caddis
Trichoptera Limnephilidae Drusus annulatus Cased caddis
Trichoptera Limnephilidae Potamophylax latipennis Cased caddis
Trichoptera Limnephilidae Cased caddis pupa
Trichoptera Goeridae Silo nigricornis Cased caddis 4
Trichoptera Odontoceridae Odontocerum albicorne Silver sedge
Trichoptera Sericostomatidae Sericostoma personatum Cased caddis 2
Diptera Ceratopogonidae Biting midge larvae 6
Diptera Chironomidae Non biting midge larvae 28
Diptera Dixidae Dixa nebulosa Meniscus midges larvae 1
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Group BMWP family Species Common name Status Abundance
Diptera Ephydridae Shore fly pupa
Diptera Empididae Dance fly larvae 1
Diptera Muscidae Limnophora riparia Stable fly larvae
Diptera Psychodidae Pericoma sp. Moth fly larvae 3
Diptera Sciomyzidae Snail killing flies larvae
Diptera Simulidae Simulium sp. Blackflies early instars not identifiable to species 46
Diptera Stratiomyidae Oxycera sp. Soldier fly larvae 3
Diptera Tipulidae cranefly larvae
Diptera Tipulidae(Pediciidae) Dicranota sp. cranefly larvae 1
Others Hydracarina Water mite 11
Others Oligochaeta True worms 33
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Group BMWP family Species Common name Status Abundance Above Drayton
Tricladida Dendrocoelidae Dendrocoelum lacteum Flatworm
Tricladida Dugesiidae Dugesia polychroa gr. Flatworm
Tricladida Planariidae Polycelis felina Flatworm 1
Tricladida Planariidae Polycelis nigra Flatworm
Tricladida Planariidae Polycelis tenuis Flatworm 16
Mollusca Physidae Physa fontinalis Bladder snail
Mollusca Lymnaeidae Galba truncatula Dwarf pond snail
Mollusca Lymnaeidae Stagnicola palustris Marsh snail =Lymnaea palustris 1
Mollusca Lymnaeidae Radix balthica Wandering snail =Lymnaea peregra 33
Mollusca Planorbidae Anisus leucostoma Button ramshorn
Mollusca Planorbidae Anisus vortex Whirlpool ramshorn 5
Mollusca Planorbidae Bathyomphalus contortus Twisted ramshorn
Mollusca Planorbidae Gyraulus crista Nautilus ramshorn 5
Mollusca Planorbidae Hippeutis complanata Flat ramshorn
Mollusca Valvatidae Valvata cristata Flat valve snail
Mollusca Valvatidae Valvata piscinalis Valve snail 8
Mollusca Ancylidae Ancylus fluviatilis River limpet 1
Mollusca Sphaeridae Pisidium sp. Pea mussel
Crustacea Asellidae Asellus aquaticus Water slater 8
Crustacea Niphargidae Niphargus aquilex Cave shrimp
Crustacea Gammaridae Gammarus pulex Freshwater shrimp 393
Hirudinea Erpobdellidae Erpobdella octoculata Leech 31
Hirudinea Erpobdellidae Trocheta subviridis Leech
Hirudinea Glossiphonidae Glossiphonia complanata Leech 43
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Group BMWP family Species
Common name Status Abundance
Hirudinea Glossiphonidae Helobdella stagnalis Leech 224
Hirudinea Glossiphonidae Theromyzon tessulatum Duck leech
Hirudinea Piscicolidae Piscicola geometra Fish leech 1
Ephemeroptera Ephemerellidae Serratella ignita Blue winged Olive 31
Ephemeroptera Baetidae Baetis rhodani Large Dark Olive 117
Ephemeroptera Baetidae Baetis vernus Medium Olive 141
Ephemeroptera Baetidae Cloeon dipterum Pond olive
Ephemeroptera Caenidae Caenis rivulorum Mayfly
Ephemeroptera Ephemeridae Ephemera danica Greendrake 1
Plecoptera Nemouridae Nemurella picteti Stonefly 3
Plecoptera Nemouridae Nemoura cinerea Stonefly
Megaloptera Sialidae Sialis lutaria Alderfly
Hemiptera Corixidae Sigara dorsalis Lesser water boatman
Hemiptera Notonectidae Notonecta viridis Greater water boatman 1
Hemiptera Gerridae Gerris sp. Water skater nymph
Hemiptera Veliidae Velia caprai Water cricket
Coleoptera Haliplidae Brychius elevatus Crawling water beetle
Coleoptera Haliplidae Haliplus lineatocollis Crawling water beetle
Coleoptera Haliplidae Haliplus sibiricus Crawling water beetle
Coleoptera Haliplidae Haliplus sp. Crawling water beetle
Coleoptera Dytiscidae Nebrioporus elegans Diving beetle
larvae not identifiable to species
Coleoptera Dytiscidae Oreodytes sanmarkii Diving beetle 74
Coleoptera Dytiscidae Diving beetle
larvae not identifiable to species
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Group BMWP family Species Common name Status
Coleoptera Hydrophilidae Anacaena limbata Scavenger water beetle
Coleoptera Hydrophilidae Helophorus brevipalpis Scavenger water beetle
Coleoptera Hydrophilidae
Scavenger water beetle
larvae not identifiable to species
Coleoptera Elmidae Elmis aenea Riffle beetle larva and adults 8
Coleoptera Elmidae Limnius volckmari Riffle beetle larva and adults
Coleoptera Elmidae Riolus subviolaceus Riffle beetle larva and adults 1
Coleoptera Scirtidae Microcara testacea Marsh beetle larva
Trichoptera Hydropsychidae Hydropsyche siltalai Caseless caddis
Trichoptera Psychomyiidae Tinodes waeneri Caseless caddis
Trichoptera Rhyacophilidae Rhyacophila dorsalis Caseless caddis
Trichoptera Glossosomatidae Agapetus fuscipes Saddle-case caddis 17
Trichoptera Hydroptilidae Hydroptila sp. Cased caddis
Trichoptera Hydroptilidae Oxyethira sp. Cased caddis
Trichoptera Leptoceridae Adicella reducta Long horned caddis
Trichoptera Limnephilidae Anabola nervosa Cased caddis
Trichoptera Limnephilidae Drusus annulatus Cased caddis
Trichoptera Limnephilidae Halesus digitatus Cased caddis
Trichoptera Limnephilidae Limnephilus lunatus Cased caddis
larvae not identifiable to species 27
larvae not identifiable to species 41
Trichoptera Limnephilidae Melampophylax mucoreus Cased caddis 6
Trichoptera Limnephilidae Micropterna lateralis Cased caddis
Trichoptera Limnephilidae Potamophylax latipennis Cased caddis
Trichoptera Limnephilidae Cased caddis
early instars not identifiable to species
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Group BMWP family Species
Common name Status Abundance
Trichoptera Goeridae Silo nigricornis Cased caddis
Trichoptera Odontoceridae Odontocerum albicorne Silver sedge
Trichoptera Sericostomatidae Sericostoma personatum Cased caddis 7
Diptera Anthomyzidae larvae
Diptera Ceratopogonidae
Biting midge larvae 14
Diptera Chironomidae Non biting midge larvae 267
Diptera Culicidae Mosquito larvae 7
Diptera Dixidae Dixa nebulosa Meniscus midge larvae 1
Diptera Empididae Clinocera sp. Dance fly larvae 18
Diptera Ephydridae Setacera sp. Shore fly larvae
Diptera Muscidae Limnophora riparia Stable fly larvae 2
Diptera Psychodidae Pericoma sp. Moth fly larvae 10
Diptera Sciomyzidae Snail killing flies larvae
Diptera Simulidae Simulium sp. Blackflies
early instars not identifiable to species 66
Diptera Stratiomyidae Soldier fly larvae
Diptera Syrphidae Hover fly larvae 1
Diptera Tipulidae cranefly larvae 15
Diptera Tipulidae (Limoniidae) cranefly larvae
Diptera Tipulidae(Pediciidae) Dicranota sp. cranefly larvae 13
Others Hydracarina Water mite 40
Others Oligochaeta True worms 488
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Group BMWP family Species Common name Status Abundance Below Drayton
Tricladida Dendrocoelidae Dendrocoelum lacteum Flatworm
Tricladida Dugesiidae Dugesia polychroa gr. Flatworm
Tricladida Planariidae Polycelis felina Flatworm
Tricladida Planariidae Polycelis nigra Flatworm
Tricladida Planariidae Polycelis tenuis Flatworm 2
Mollusca Physidae Physa fontinalis Bladder snail 2
Mollusca Lymnaeidae Galba truncatula Dwarf pond snail 1
Mollusca Lymnaeidae Radix balthica Wandering snail =Lymnaea peregra 1
Mollusca Planorbidae Anisus leucostoma Button ramshorn
Mollusca Planorbidae Anisus vortex Whirlpool ramshorn 50
Mollusca Planorbidae Bathyomphalus contortus Twisted ramshorn
Mollusca Planorbidae Gyraulus crista Nautilus ramshorn 2
Mollusca Planorbidae Hippeutis complanata Flat ramshorn
Mollusca Valvatidae Valvata cristata Flat valve snail 1
Mollusca Valvatidae Valvata piscinalis Valve snail 2
Mollusca Ancylidae Ancylus fluviatilis River limpet 44
Mollusca Sphaeridae Pisidium sp. Pea mussel 4
Crustacea Asellidae Asellus aquaticus Water slater 17
Crustacea Niphargidae Niphargus aquilex Cave shrimp 2
Crustacea Gammaridae Gammarus pulex Freshwater shrimp 283
Hirudinea Erpobdellidae Erpobdella octoculata Leech 8
Hirudinea Erpobdellidae Trocheta subviridis Leech
Hirudinea Glossiphonidae Glossiphonia complanata Leech 62
Hirudinea Glossiphonidae Helobdella stagnalis Leech 4
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Group BMWP family Species
Common name Status Abundance
Hirudinea Glossiphonidae Theromyzon tessulatum Duck leech 1
Hirudinea Piscicolidae Piscicola geometra Fish leech
Plecoptera Leuctridae Leuctra fusca Stonefly 2
Plecoptera Leuctridae Leuctra geniculata Stonefly
Plecoptera Nemouridae Nemurella picteti Stonefly 3
Ephemeroptera Ephemerellidae Serratella ignita Blue winged Olive 20
Ephemeroptera Baetidae Baetis rhodani Large Dark Olive 7
Ephemeroptera Baetidae Baetis vernus Medium Olive 62
Ephemeroptera Caenidae Caenis rivulorum Mayfly
Ephemeroptera Ephemeridae Ephemera danica Greendrake
Megaloptera Sialidae Sialis lutaria Alderfly 4
Odonata Calopterygidae Calopteryx virgo Beautiful demoiselle 2
Hemiptera Corixidae Sigara dorsalis Lesser water boatman
Hemiptera Gerridae Gerris sp. Water skater nymph
Hemiptera Veliidae Velia caprai Water cricket 2
Coleoptera Haliplidae Brychius elevatus Crawling water beetle
Coleoptera Haliplidae Haliplus lineatocollis Crawling water beetle 2
Coleoptera Haliplidae Haliplus sibiricus Crawling water beetle 1
Coleoptera Haliplidae Haliplus sp. Crawling water beetle
larvae not identifiable to species 4
Coleoptera Dytiscidae Oreodytes sanmarkii Diving beetle 37
Coleoptera Dytiscidae Platambus maculatus Diving beetle 1
Coleoptera Dytiscidae Diving beetle
larvae not identifiable to species 7
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Group BMWP family Species
Common name Status Abundance
Coleoptera Hydrophilidae Anacaena globulus Scavenger water beetle
Coleoptera Hydrophilidae Helophorus brevipalpis Scavenger water beetle
Coleoptera Elmidae Elmis aenea Riffle beetle larva and adults 132
Coleoptera Elmidae Limnius volckmari Riffle beetle larva and adults 4
Coleoptera Elmidae Riolus subviolaceus Riffle beetle larva and adults 1
Coleoptera Scirtidae Microcara testacea Marsh beetle larva
Trichoptera Hydropsychidae Hydropsyche siltalai Caseless caddis 1
Trichoptera Polycentropodidae Plectrocnema conspersa Caseless caddis 1
Trichoptera Psychomyiidae Lype reducta Caseless caddis 1
Trichoptera Rhyacophilidae Rhyacophila dorsalis Caseless caddis 2
Trichoptera Glossosomatidae Agapetus fuscipes Saddle case caddis 4
Trichoptera Hydroptilidae Hydroptila sp. Cased caddis
Trichoptera Hydroptilidae Oxyethira sp. Cased caddis
Trichoptera Leptoceridae Adicella reducta Long horned caddis
larvae not identifiable to species 1
larvae not identifiable to species 4
Trichoptera Beraeidae Beraeodes minutus Cased caddis 19
Trichoptera Limnephilidae Anabola nervosa Cased caddis
Trichoptera Limnephilidae Drusus annulatus Cased caddis
Trichoptera Limnephilidae Halesus digitatus Cased caddis
Trichoptera Limnephilidae Limnephilus lunatus Cased caddis 1
Trichoptera Limnephilidae Limnephilus marmoratus Cased caddis 7
Trichoptera Limnephilidae Melampophylax mucoreus Cased caddis 6
Trichoptera Limnephilidae Micropterna lateralis Cased caddis
Trichoptera Limnephilidae Potamophylax cingulatus Cased caddis 1
Trichoptera Limnephilidae Potamophylax latipennis Cased caddis 5
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Group BMWP family Species
Trichoptera Limnephilidae
Trichoptera Phryganeidae Phryganea bipunctata
Common name Status Abundance
Cased caddis
early instars not identifiable to species
Cased caddis 1
Trichoptera Goeridae Silo nigricornis Cased caddis
Trichoptera Odontoceridae Odontocerum albicorne Silver sedge
Trichoptera Sericostomatidae Sericostoma personatum Cased caddis 1
Diptera Anthomyzidae larvae
Diptera Ceratopogonidae
Diptera Chironomidae
Biting midge larvae 5
Non biting midge larvae 53
Diptera Culicidae Anopheles sp. Mosquito larvae 1
Diptera Dixidae Dixa nebulosa Meniscus midge larvae 1
Diptera Ephydridae Shore flies pupae
Diptera Muscidae Limnophora riparia Stable fly pupae
Diptera Psychodidae Pericoma sp. Moth fly larvae 1
Diptera Sciomyzidae
Snail killing flies larvae
Diptera Simulidae Simulium sp. Blackflies
early instars not identifiable to species 70
Diptera Stratiomyidae Oxycera nigricornis Delicate Soldier fly larvae
Diptera Tipulidae cranefly larvae
Diptera Tipulidae (Limoniidae) cranefly larvae
Diptera Tipulidae(Pediciidae) Dicranota sp. cranefly larvae 1
Others Hydracarina Water mite 45
Others Oligochaeta True worms 71
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Group BMWP family Species
Common name Status Abundance Manor Farm
Tricladida Dendrocoelidae Dendrocoelum lacteum Flatworm 1
Tricladida Dugesiidae Dugesia polychroa gr. Flatworm 1
Tricladida Planariidae Polycelis felina Flatworm
Tricladida Planariidae Polycelis nigra gr. Flatworm 2
Tricladida Planariidae Polycelis tenuis Flatworm 66
Mollusca Physidae Physa fontinalis Bladder snail 14
Mollusca Lymnaeidae Galba truncatula Dwarf pond snail =Lymnaea truncatula 2
Mollusca Lymnaeidae Radix balthica Wandering snail =Lymnaea peregra 11
Mollusca Lymnaeidae Stagnicola palustris Marsh snail =Lymnaea palustris
Mollusca Planorbidae Anisus leucostoma Button ramshorn
Mollusca Planorbidae Anisus vortex Whirlpool ramshorn 7
Mollusca Planorbidae Bathyomphalus contortus Twisted ramshorn Planorbidae Planorbarius corneus Great ramshorn
Mollusca Valvatidae Valvata cristata Flat valve snail 15
Mollusca Valvatidae Valvata piscinalis Common valve snail
Mollusca Ancylidae Acroloxus lacustris Lake limpet
Mollusca Ancylidae Ancylus fluviatilis River limpet 34 Sphaeridae Sphaerium corneum Horny orb mussel
Mollusca Sphaeridae Pisidium sp. Pea mussel 2
Crustacea Asellidae Asellus aquaticus Water slater 169
Crustacea Gammaridae Gammarus pulex Freshwater shrimp 3020
Hirudinea Erpobdellidae Erpobdella octoculata Leech 65
Hirudinea Erpobdellidae Trocheta subviridis Leech
Hirudinea Glossiphonidae Alboglossiphonia heteroclita Leech 1
26
Group BMWP family Species
Common name Status Abundance
Hirudinea Glossiphonidae Glossiphonia complanata Leech 12
Hirudinea Glossiphonidae Helobdella stagnalis Leech 1
Hirudinea Glossiphonidae Theromyzon tessulatum Duck leech 2
Hirudinea Piscicolidae Piscicola geometra Fish leech 3
Plecoptera Leuctridae Leuctra fusca Stonefly
Plecoptera Nemouridae Nemurella picteti Stonefly 17
Ephemeroptera Ephemerellidae Serratella ignita Blue winged Olive 8
Ephemeroptera Baetidae Baetis rhodani Large Dark Olive 75
Ephemeroptera Baetidae Baetis vernus Medium Olive 50
Ephemeroptera Caenidae Caenis luctuosa Mayfly
Ephemeroptera Caenidae Caenis rivulorum Mayfly
Ephemeroptera Ephemeridae Ephemera danica Greendrake
Ephemeroptera Heptageniidae Rithrogena semicolorata Olive upright
Megaloptera Sialidae Sialis lutaria Alderfly
Hemiptera Gerridae Gerris sp. Water skater nymph
Hemiptera Veliidae Velia caprai Water cricket nymph 1
Hemiptera Corixidae Water boatman nymph
Coleoptera Haliplidae Haliplus lineatocollis Crawling water beetle
Coleoptera Haliplidae Haliplus sp. Crawling water beetle larvae not identifiable to species
Coleoptera Dytiscidae Oreodytes sanmarkii Diving beetle
Coleoptera Hydrophilidae Dactylosternum abdominale Scavenger water beetle
Coleoptera Hydrophilidae Laccobius bipunctatus Water beetle 1
Coleoptera Elmidae Elmis aenea Riffle beetle larva and adults 50
Coleoptera Elmidae Limnius volckmari Riffle beetle larvae 1
27
Group BMWP family Species
Common name Status Abundance
Coleoptera Elmidae Riolus sp. Riffle beetle larvae
Coleoptera Scirtidae Elodes sp. Marsh beetle larva
Trichoptera Hydropsychidae Diplectrona felix Caseless caddis
Trichoptera Hydropsychidae Hydropsyche siltalai Caseless caddis 2
Trichoptera Psychomyiidae Lype reducta Caseless caddis 1
Trichoptera Rhyacophilidae Rhyacophila dorsalis Caseless caddis 7
Trichoptera Glossosomatidae Agapetus fuscipes Saddle case caddis 7
Trichoptera Hydroptilidae Agraylea sexmaculata Cased caddis
Trichoptera Hydroptilidae Hydroptila sp. Cased caddis
larvae not identifiable to species 8
Trichoptera Hydroptilidae Ithytrichia sp. Cased caddis larvae not identifiable to species
Trichoptera Hydroptilidae Oxyethira sp. Cased caddis
Trichoptera Leptoceridae Adicella reducta Long horned caddis
Trichoptera Limnephilidae Limnephilus lunatus Cased caddis
larvae not identifiable to species 49
Trichoptera Limnephilidae Melampophylax mucoreus Cased caddis 2
Trichoptera Limnephilidae Potamophylax latipennis Cased caddis 1
Trichoptera Limnephilidae Cased caddis early instars not identifiable to species
Trichoptera Goeridae Silo nigricornis Cased caddis 6
Trichoptera Odontoceridae Odontocerum albicorne Silver sedge 1
Trichoptera Sericostomatidae Sericostoma personatum Cased caddis 1
Diptera Ceratopogonidae
Diptera Chironomidae
Biting midge larvae 8
Non biting midge larvae 46
Diptera Dixidae Dixa sp. Meniscus midges larvae 7
Diptera Empididae Dance fly larvae
Diptera Ephydridae Shore fly pupa and larva
28
Group BMWP family Species Common name Status Abundance
Diptera Muscidae Limnophora riparia Stable fly pupa and larva 5
Diptera Psychodidae Pericoma sp. + Psychoda sp. Moth fly larvae 12
Diptera Sciomyzidae Snail killing flies larvae
Diptera Simulidae Simulium ornatum gr. Blackflies early instars not identifiable to species 18
Diptera Stratiomyidae Soldier fly larvae 3
Diptera Tipulidae cranefly larvae
Diptera Tipulidae(Pediciidae) Dicranota sp. cranefly larvae
Diptera Tipulidae(Pediciidae) Pedicia sp. cranefly larvae
Others Hydracarina Water mite 4
Others Oligochaeta True worms 118
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