Aquatic Invertbrate

Macroinvertebrate Survey of three watercress farm outflows, Alresford , Hants

Report prepared by Robert Aquilina MSc MCIEEM

June 2018

Macroinvertebrate survey of three watercress farm outflows, Alresford, Hants

Robert Aquilina MSc MCIEEM

June 2018

Robert Aquilina MSc MCIEEM is an independent consulting ecologist specialising in protected species and freshwater ecology. He is a Full member of the Institute of Ecology and Environmental Management and abides by their Code of Professional Conduct. For further details see www.cieem.net www.aquilina-environmental.co.uk

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Table of contents Summary ................................................................................................................ 4 Introduction ........................................................................................................... 5 Methods................................................................................................................. 5 BMWP ......................................................................................................................................... 6 WHPT .......................................................................................................................................... 6 Locations ..................................................................................................................................... 7

Results ................................................................................................................... 9 Conclusions ...........................................................................................................11 References ............................................................................................................11 Appendix 1 Species recorded. ................................................................................12

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Summary

Macroinvertebrate surveys of outflows from Bishop’s Sutton, Drayton and Manor Farm watercress farms at Alresford, Hampshire were carried out using standard sampling techniques. The purpose was to establish a baseline for future monitoring based on standard methodologies in order to 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 and BMWP) scores.

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Introduction

The purpose of this survey was to assess the discharge from the watercress beds at Bishop’s Sutton, Drayton and Manor Farm around Alresford and identify any impacts that they may be having downstream. 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.

The site was visited by Robert Aquilina on Tuesday 22nd May 2018 and samples were collected for analysis in the laboratory using standard techniques. The weather conditions were dry and suitable for the survey with normal water flow levels.

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 standard BMWP and its more sophisticated modification WHPT. 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.

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. The standard BMWP invertebrate groups were 5

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 AB1 AB2 AB3 AB4

1-9 10 -99 100 - 999 >1000 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 and ASPT.

Locations

The Bishop’s Sutton outflow is located at SU 60400 32321.

Photograph 1: Bishop’s Sutton outflow The outflow channel is canalised and subject to fast deep flow. There is a gravel bed with strong Ranunculus growth but the banks are vertical stone with little vegetation. Therefore mesohabitats were limited to gravel, Ranunculus, marginal

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vegetation and the Fontinalis moss growing downstream of the weir. Sampling was concentrated in the Ranunculus and gravel.

The Drayton outflow was located at SU 59358 33272.

Photograph 2: Drayton outflow The sample reach was downstream of a bridge with culverts discharging the water, leading to scour in the channel bed. Despite this, 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.

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The Manor Farm outflow is located at SU 58532 33516.

Photograph 3: Manor Farm outflow.

The habitats present consisted of cobbles, small stone, gravel, coarse sand, Ranunculus beds and marginal watercress. Each was sampled for thirty seconds.

There was noticeably less in-channel and marginal vegetation than on the previous visit (November 2016).

Results

The full species lists and abundance are presented as an appendix. The results summarised here consist of BMWP, N-taxa and ASPT as well as WHPT, N-taxa and ASPT. These are presented by site as well as by index for comparative purposes.

A previous visit to Manor Farm had taken place in November 2016 when a standard sample had been collected and BMWP scores calculated. These are included in the results here for comparison but note that it represents a completely different season 9

(autumn as opposed to spring). It was possible to calculate the WHPT scores associated with this previous visit because the full inventory of species was recorded with abundance and included the full suite of Dipteran families.

Index

Manor Farm Drayton Bishop’s Sutton Nov 2016 May 2018

# contributing taxa BMWP ASPT Total # taxa

30 163 5.43

29 160 5.52

31 164 5.29

29 159 5.48

51

53

47

49

Table 2. BMWP results summary

Index

Manor Farm Drayton Bishop’s Sutton Nov 2016 May 2018

# contributing taxa WHPT ASPT

36.0 188.7 5.24

38.0 204.8 5.39

34.0 174.8 5.14

35.0 194.6 5.56

Table 3. WHPT results summary

Site Manor Farm (Nov 2016) Manor Farm (May 2018) Drayton Bishop’s Sutton

BMWP WHPT N-taxa (BMWP) 163 188.7 30

N-taxa (WHPT) 36

ASPT (BMWP) 5.43

ASPT (WHPT) 5.24

160

204.8

29

38

5.52

5.39

164 159

174.8 194.6

31 29

34 35

5.29 5.48

5.14 5.56

Table 4. BMWP v WHPT results comparison

The results show an increase of WHPT score over BMWP as expected due to the increased number of contributing taxa (N-taxa). Except for Bishop’s Sutton, WHPT ASPT scores are lower, again as expected due to the increased N-taxa.

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Conclusions The results provide a baseline for future monitoring (scheduled for September 2018).

Interpretation would be expected to follow from a RICT (River Invertebrate Classification Tool) analysis in order to provide EQI’s from reference condition that can be related to Water Framework Directive bands. However, this is not the point of this exercise.

It is clear that WHPT will provide a more accurate indication of water quality and that regular sampling will provide a check on the effects of watercress management activities upon the streams, but also on the seasonal changes to be expected.

WHPT scores are comparable between sites and also between season for Manor Farm.

References Aquilina, R. (2016). Macroinvertebrate Survey of Manor Farm outflow, Old Alresford, Hants.

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 abundancerelated scores from field data. River Research and Appications. 30: 887-904.

RMA Environmental. (2012). Invertebrate Monitoring Spring 2012, The River Alre Catchment and Alresford Pond New Alresford, Hampshire.

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Appendix 1 Species recorded.

Group

BMWP family

Species

Common name

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

Mollusca

Physidae

Physa fontinalis

Bladder snail

Mollusca

Lymnaeidae

Lymnaea palustris

Marsh Pond snail

Mollusca

Lymnaeidae

Radix balthica

Wandering snail

Mollusca

Planorbidae

Anisus leucostoma

Mollusca

Planorbidae

Anisus vortex

Button ramshorn Whirlpool ramshorn

Mollusca

Planorbidae

Bathyomphalus contortus

Twisted ramshorn

Mollusca

Valvatidae

Valvata cristata

Mollusca

Valvatidae

Valvata piscinalis

Flat valve snail Common valve snail

Mollusca

Ancylidae

Ancylus fluviatilis

River limpet

Crustacea

Asellidae

Asellus aquaticus

Water slater

Crustacea

Gammaridae

Gammarus pulex

Freshwater shrimp

Hirudinea

Erpobdellidae

Erpobdella octoculata

Leech

Hirudinea

Erpobdellidae

Trocheta subviridis

Leech

Notes

Abundance

BMWP

WHPT

Bishops Sutton 1 2 13 20 17

5 5

3.0 2.8

5.4

1 17

3

2.5

1

3

3.3

6

5.8 2.3 4.6 2.0

1 8 84 323 30

3 6 3

Group

BMWP family

Species

Common name

Hirudinea

Glossiphonidae

Glossiphonia complanata

Leech

Hirudinea

Glossiphonidae

Helobdella stagnalis

Leech

Hirudinea

Glossiphonidae

Theromyzon tessulatum

Duck leech

Hirudinea

Piscicolidae

Piscicola geometra

Fish leech

Plecoptera

Nemouridae

Nemurella picteti

Stonefly

Ephemeroptera

Ephemerellidae

Serratella ignita

Blue-winged Olive

Ephemeroptera

Baetidae

Baetis rhodani

Large Dark Olive

Ephemeroptera

Baetidae

Baetis vernus

Medium Olive

Ephemeroptera

Caenidae

Caenis sp.

Mayfly

Hemiptera

Gerridae

Gerris sp.

Water skater

Hemiptera

Veliidae

Velia caprai

Coleoptera

Haliplidae

Brychius elevatus

Water cricket Crawling water beetle

Coleoptera

Haliplidae

Haliplus lineatocollis

Crawling water beetle

Coleoptera

Haliplidae

Haliplus sp.

Crawling water beetle

Coleoptera

Dytiscidae

Oreodytes sanmarkii

Diving beetle

Coleoptera

Elmidae

Elmis aenea

Riffle beetle

Coleoptera

Elmidae

Riolus subviolaceus

Riffle beetle

Coleoptera

Scirtidae

Microcara testacea

Marsh beetle

Trichoptera

Hydropsychidae

Caseless caddis

Trichoptera

Polycentropodidae

Hydropsyche siltalai Polycentropus flavomaculatus

Trichoptera

Rhyacophilidae

Rhyacophila dorsalis

Caseless caddis

Trichoptera

Glossosomatidae

Agapetus fuscipes

Saddle-case caddis

Trichoptera

Hydroptilidae

Hydroptila sp.

Cased caddis

Caseless caddis

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Notes

local

local

Abundance

BMWP

WHPT

7 2

3

3.4

2 1 162 36 106

4 7

5.2 8.7

10

9.0

4

7.2

1 1

5

5.2 4.5

7 1 6 5 39 4 2 12

5

3.4

5

4.5

5

7.4

5

7.2

1 14 21 58

7

8.2

7

9.2

7

7.6

6

6.5

6.9

Group

BMWP family

Species

Common name

Trichoptera

Hydroptilidae

Oxyethira sp.

Cased caddis

Trichoptera

Leptoceridae

Mystacides sp.

Long-horned caddis

Trichoptera

Limnephilidae

Drusus annulatus

Cased caddis

Trichoptera

Limnephilidae

Limnephilus lunatus

Cased caddis

Trichoptera

Limnephilidae

Potamophylax latipennis

Cased caddis

Trichoptera

Goeridae

Silo nigricornis

Cased caddis

Trichoptera

Odontoceridae

Odontocerum albicorne

Silver sedge

Trichoptera

Sericostomatidae

Sericostoma personatum

Cased caddis

Diptera

Ceratopogonidae

Biting midge

Diptera

Chironomidae

Non-biting midge

Diptera

Ephydridae

Shore fly

Diptera

Psychodidae

Moth fly

Diptera

Sciomyzidae

Snail-killing flies

Diptera

Simulidae

Diptera

Stratiomyidae

Soldier fly

Diptera

Tipulidae

cranefly

Diptera

Tipulidae(Pediciidae)

cranefly

Others

Hydracarina

Water mite

Others

Oligochaeta

True worms

Simulium sp.

Notes

Abundance

WHPT

2 2 7 2 3 2 14 15 97 1

2 1

Blackflies

38 45 # taxa score ASPT

14

BMWP

49 1237

7

6.9

10

8.8

10

11.1

10

9.4 5.5

2

1.3

4.4

5

5.5 3.6

1

2.3

29 159 5.48

35.0 194.6 5.56

Group

BMWP family

Species

Common name

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

Mollusca

Physidae

Physa fontinalis

Bladder snail

Mollusca

Lymnaeidae

Radix balthica

Mollusca

Planorbidae

Anisus leucostoma

Mollusca

Planorbidae

Mollusca

Planorbidae

Anisus vortex Bathyomphalus contortus

Mollusca

Valvatidae

Valvata cristata

Flat valve snail

Mollusca

Ancylidae

Ancylus fluviatilis

River limpet

Mollusca

Sphaeridae

Pisidium sp.

Pea mussel

Crustacea

Asellidae

Asellus aquaticus

Water slater

Crustacea

Gammaridae

Gammarus pulex

Freshwater shrimp

Hirudinea

Erpobdellidae

Erpobdella octoculata

Leech

Hirudinea

Erpobdellidae

Leech

Hirudinea

Glossiphonidae

Trocheta subviridis Glossiphonia complanata

Hirudinea

Glossiphonidae

Helobdella stagnalis

Leech

Notes

Abundance

BMWP

WHPT

Drayton

1

5

4.7

Wandering snail

33

3

2.5

Button ramshorn Whirlpool ramshorn

25

3

3.0

3 4 88 12 91 3

3

3.3

6

5.8

6

Twisted ramshorn

Leech

15

3

3.5

3 3

2.3 4.5 3.6

3

3.4

6

Group

BMWP family

Species

Common name

Hirudinea

Glossiphonidae

Theromyzon tessulatum

Hirudinea

Piscicolidae

Piscicola geometra

Fish leech

Ephemeroptera

Ephemerellidae

Serratella ignita

Blue-winged Olive

Ephemeroptera

Baetidae

Baetis vernus

Medium Olive

Ephemeroptera

Caenidae

Caenis rivulorum

Mayfly

Ephemeroptera

Ephemeridae

Ephemera danica

Greendrake

Megaloptera

Sialidae

Sialis lutaria

Alderfly

Hemiptera

Corixidae

Sigara venusta

Lesser water boatman

Hemiptera

Gerridae

Gerris sp.

Water skater

Hemiptera

Veliidae

Velia caprai

Water cricket

Coleoptera

Haliplidae

Brychius elevatus

Crawling water beetle

Coleoptera

Haliplidae

Haliplus lineatocollis

Coleoptera

Haliplidae

Haliplus sibiricus

Crawling water beetle Crawling water beetle local

Coleoptera

Haliplidae

Haliplus sp.

Crawling water beetle

Coleoptera

Dytiscidae

Oreodytes sanmarkii

Diving beetle

Coleoptera

Hydrophilidae

Anacaena globulus

Scavenger water beetle

Coleoptera

Hydrophilidae

Helophorus brevipalpis

Scavenger water beetle

Coleoptera

Elmidae

Elmis aenea

Riffle beetle

Coleoptera

Elmidae

Riolus subviolaceus

Riffle beetle

Coleoptera

Scirtidae

Microcara testacea

Marsh beetle

Trichoptera

Hydropsychidae

Hydropsyche siltalai

Caseless caddis

Trichoptera

Psychomyiidae

Lype reducta

Caseless caddis

Trichoptera

Rhyacophilidae

Rhyacophila dorsalis

Caseless caddis

16

Notes

Abundance

BMWP

WHPT

36 10 2 2 11 1 1

10

8.5

4

5.9

7

5

6.5 8.3 4.4 3.7 5.2

2 11

5

3.4

5 5

4.8 5.8

5

7.4

12 2 10 1 1 69 2 7 1 1

10 4 5

6.9 5

5.8

8

5.8

7

8.1

Group

BMWP family

Species

Common name

Trichoptera

Glossosomatidae

Agapetus fuscipes

Saddle-case caddis

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

Limnephilus lunatus

Cased caddis

Trichoptera

Limnephilidae

Micropterna lateralis

Cased caddis

Trichoptera

Limnephilidae

Potamophylax latipennis

Cased caddis

Trichoptera

Limnephilidae

Trichoptera

Goeridae

Silo nigricornis

Cased caddis

Trichoptera

Odontoceridae

Odontocerum albicorne

Silver sedge

Trichoptera

Sericostomatidae

Sericostoma personatum

Cased caddis

Diptera

Anthomyzidae

Diptera

Ceratopogonidae

Biting midge

Diptera

Chironomidae

Non-biting midge

Diptera

Dixidae

Dixa nebulosa

Meniscus midge

Diptera

Psychodidae

Pericoma sp.

Moth fly

Diptera

Sciomyzidae

Diptera

Simulidae

Diptera

Stratiomyidae

Soldier fly

Diptera

Tipulidae

cranefly

Diptera

Tipulidae(Pediciidae)

Others

Hydracarina

Cased caddis

Notes

Abundance

7 4 1 4 9 27 2 8 2

BMWP

WHPT

6

6.5

10

6.7

7

6.9

16 1 11 25

10

9.4

2

1.3

1 1

5

5.5

5.5

Snail-killing flies Simulium sp.

Dicranota sp.

Blackflies

cranefly

190

Water mite

17

3.6

Group

BMWP family

Others

Oligochaeta

Species

Common name

Notes

True worms

# taxa score ASPT

18

Abundance

BMWP

WHPT

56

1

2.3

47 813

31 164 5.29

34.0 174.8 5.14

Group

BMWP family

Species

Common name

Notes

Abundance

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

Mollusca

Physidae

Physa fontinalis

Bladder snail

Mollusca

Lymnaeidae

Radix balthica

Wandering snail

1 15 3 2

Mollusca

Planorbidae

Anisus leucostoma

Mollusca

Planorbidae

12

Mollusca

Planorbidae

Anisus vortex Bathyomphalus contortus

Button ramshorn Whirlpool ramshorn

Mollusca

Valvatidae

Valvata cristata

Mollusca

Valvatidae

Valvata piscinalis

Flat valve snail Common valve snail

Mollusca

Ancylidae

Ancylus fluviatilis

River limpet

Mollusca

Sphaeridae

Pisidium sp.

Pea mussel

Crustacea

Asellidae

Asellus aquaticus

Water slater

Crustacea

Gammaridae

Gammarus pulex

Freshwater shrimp

Hirudinea

Erpobdellidae

Erpobdella octoculata

Leech

Hirudinea

Erpobdellidae

Leech

Hirudinea

Glossiphonidae

Trocheta subviridis Glossiphonia complanata

Hirudinea

Glossiphonidae

Helobdella stagnalis

Leech

BMWP

WHPT

Manor Farm

5

5.4

3

2.7

3

3.6

3

3.0

2 7 1 125 638 62

3

3.1

6

3

5.8 4.4 0.8 4.6 2.0

1 2

3

3.4

Twisted ramshorn

Leech

19

16

3 3 6

Group

BMWP family

Species

Common name

Notes

Hirudinea

Glossiphonidae

Theromyzon tessulatum

Hirudinea

Piscicolidae

Piscicola geometra

Fish leech

Ephemeroptera

Ephemerellidae

Serratella ignita

Blue-winged Olive

Ephemeroptera

Baetidae

Baetis rhodani

Large Dark Olive

Ephemeroptera

Baetidae

Baetis vernus

Medium Olive

Ephemeroptera

Caenidae

Caenis luctuosa

Mayfly

Ephemeroptera

Caenidae

Caenis rivulorum

Mayfly

Ephemeroptera

Ephemeridae

Ephemera danica

Greendrake

Ephemeroptera

Heptageniidae

Rithrogena semicolorata

Upright

Hemiptera

Gerridae

Gerris sp.

Water skater

Hemiptera

Veliidae

Velia caprai

Coleoptera

Haliplidae

Haliplus sibiricus

Water cricket Crawling water beetle

Coleoptera

Haliplidae

Haliplus sp.

Crawling water beetle

Coleoptera

Dytiscidae

Oreodytes sanmarkii

Diving beetle

Coleoptera

Hydrophilidae

Helophorus sp.

Scavenger water beetle

Coleoptera

Elmidae

Elmis aenea

Riffle beetle

Coleoptera

Elmidae

Limnius volckmari

Riffle beetle

Coleoptera

Scirtidae

Microcara testacea

Marsh beetle

Trichoptera

Hydropsychidae

Hydropsyche siltalai

Caseless caddis

Trichoptera

Rhyacophilidae

Rhyacophila dorsalis

Caseless caddis

Trichoptera

Glossosomatidae

Agapetus fuscipes

Saddle-case caddis

Trichoptera

Hydroptilidae

Agraylea sp.

Cased caddis

Trichoptera

Hydroptilidae

Hydroptila sp.

Cased caddis

Abundance

BMWP

WHPT

2

20

local

124 77 26 1 82 9 1 1

10

9.0

4

7.2

7

6.5

10 5

8.3 8.5 5.2

1 1 1 1 64 9 1 94 1 3 1 31

5

3.6

10

4.5 5.8 5

7.4

6.9 5

7.2

7

8.1 7.8

6

6.5

Group

BMWP family

Species

Common name

Trichoptera

Hydroptilidae

Ithytrichia sp.

Cased caddis

Trichoptera

Hydroptilidae

Oxyethira sp.

Cased caddis

Trichoptera

Leptoceridae

Adicella reducta

Long-horned caddis

Trichoptera

Limnephilidae

Limnephilus lunatus

Cased caddis

Trichoptera

Limnephilidae

Potamophylax latipennis

Cased caddis

Trichoptera

Limnephilidae

Trichoptera

Goeridae

Silo nigricornis

Cased caddis

Trichoptera

Odontoceridae

Odontocerum albicorne

Silver sedge

Trichoptera

Sericostomatidae

Sericostoma personatum

Cased caddis

Diptera

Ceratopogonidae

Biting midge

Diptera

Chironomidae

Non-biting midge

Diptera

Ephydridae

Shore fly

Diptera

Muscidae

Limnophora riparia

Stable fly

Diptera

Psychodidae

Pericoma sp.

Moth fly

Diptera

Sciomyzidae

Diptera

Simulidae

Diptera

Stratiomyidae

Soldier fly

Others

Hydracarina

Water mite

Others

Oligochaeta

True worms

Notes

Abundance

1 3 1 5 1 2

Cased caddis

BMWP

WHPT

10

6.7

7

5.9

32 1 35 25 3 1 8

10

10.3

10

8.9 5.5

2

1.3

76 3 24 36

5

1

2.3

53 1675

29 160 5.52

38.0 204.8 5.39

4.4 4.0 4.5

Snail-killing flies Simulium sp.

Blackflies

# taxa score ASPT

21

6.1 3.6