A CONTRI'BUTION TO A BI.OLOGICAL RESOURCE RESIDENT; SUBIVERGED, MACROPHYTES AND
PART 3: A SYL.T'IqiS OF' SUPJEYS DURII\G APRIL 1995 ANTD JAI.TUARY 1996
Pr:epared for: Prepared by: Carter Holt Harvey Private Bag. TOKOROA ij¡iañ Or:ffey
Inquiries and ref'erence: please quote Bnan T. Coffey anci Associateq Limited BBRI / L. Maraetai I 03 C.FI.H.. January 1995
3?3.€t52 csp lcrest, Ha6ilron. New Zealand. Telephone lFax 64 [07] 856 1233. Mobile: (0?-5) 937 865 1.O SummarY
reporl provides a baseline description of:
. resident, submerged, macrophytes and invertebrates in water less than 30 m deep, across 12 cross sectÍons of Lake Maraetai., during April - May 1995
deep water benthos (30 - 60 m depth) at selected sites in Lake Maraetai during January 1996.
Lake Maraetai is a man-made hydro-electric reservoÍr whÍch flooded a former steep-sided gorge formed by the V/aikato River. It is a highly turbid and enriched lake in which introduced plants and animals dominated littoral communities.
Treated wastewater from the Kinleith Pulp and Paper MiIl is discharged into Lake Maraetai via the Kopakorahi Stream. The Kopakorahi Arm is on the right bank, in the middle section of the lake.
ee differences in the structure of resident, bmerged, macrophyte and invertebrate communities ve been identified between the upstream and sections of lake Maraetai.
. The depth of the photic zorLe for submerged macrophytes and epipelic periphyton in the downstream section of Lake Maraetai is reduced relatjve to the upstream section of the lake.
. There is an increased frequency / abundance of "pollution indicators" in the downstream section of the Lake Maraetai including the Kopakorahi Arm of the lake.
. There is a reduced abundance of deep water benthos in t]:e downstream section of the lake,
Brian T, Coffey and Associates Limited, Hamilron However it Ís noted that a viable benthic community s present throughout the deepest mainstream i of the lake during (.: : January 1996.
\ ttoral beds of submerged macfophytes were dominated by two introduced lakewee ds, Ceratophgllum and Egería. d.ensa.
e most restricted depth range of submerged rophytes \¡/as recorded in the Kopakora_hi Arm of the lake.
Periphyton in the canopy of submerged weed beds was enerally dominated by the non-attached green alga Enteromorpha no:na.
Macrobenthos such as the freshwate¡ musser HyrídeLLa menzíesí and the freshwater crayfish paranephrops Lanifrons were present on stable (well_consolidated) ubstrata in the main channel of the lake.
low frequency of the freshwater spon ge Ephgdatía kakahuensis was present throughout the mainstream cha¡rnel of tl:e lake.
enthic communities in depositional zones between rter depths of 12 to 25 m comprised a low diversity of bificid worms, chironomid larvae, ostracods and pea ssels.
Below 30 m depth, lake bed sediments supported a low diversity of benthic organisms (almost exclusively larvae of the non-biting midge Chíronomus zelandícus and a single species of an unidentified tubificid worm).
The dominant component of surficial, deep_water, sediments deposited in t].e old river channel at depths of 35 to 60 m was plankton debris, dominated by frustules of chain-forming species of the diatom MeLosíra..
generally most common in the upstream section of the lake or which were not recorded in the downstream tion of the lake included the macrophytes ELod_ea
Brian T. Coffey and Associates Limited, Hamitton cc,nc,densis, MgriophgLLum triphgLLum, and Nitell.a hookerí: the mosses Drepanocladus adnuncus, urhgnchium austrinum, Fissidens rigiduLus, y pno dendr on mar g inatum a,nd Tr ido ntium tas manic a; cyanobacterium OsciLLatoria rubescens; a species of the filamentous alga Mtcrospora: the snails Potamopgrgus antipodarum, Lgmnaea tomento s a and GgrauLtts corinnai the bryozoan PLumateLl"a repens and the leech Glossþhonia. multístriata. Elsewhere in New d freshwaters, these species are generally associated with relatively high water quality.
recorded as present only in the downstream section of the lake included species of the cyanobacteria genera Anabaena, Schízothnx and ToLgpothnx and the hed green filamentous alga Cladophora gLomerata. in New Zealand freshwaters, these taxa are neraliy associated with relatively low water quatity.
eed bed fauna for which the highest replicate counts were recorded in the Kopakorahi Arm included amphipods, tubificid worrns and the snail Phgsa acuta.
The mixing patterns of highly-coloured water entering Lake Maraetai from the Kopakorahi Arm were clearly complex, related to season (Zuur, 1989) and dependant on local weather conditions.
Physical and chemical characters of the lake, together with a description of fish populations, were the subject of concurrent studies to describe receiving waters fo¡ treated wastewater from the Kinleith Pulp and Paper Mill (the Kopakorahi Arm of Lake Maraetai).
e extent to which differences in submerged community structure can be associated with the Íscharge of bleached kraft mill effluent from the Kinleith Mill to the Kopakorahi Arm of Lake Maraetai 1 depend on the findings of these complementary dies. These collective data are to be collated and reported on by Kingett Mitchell a¡rd Associates Limited.
Brian T. Coffey and Associates Limited, Hamilton 2,O Introduction
This report provides
a description of resident, submerged, macroscopic biological communities in water less than 30 m deep across 12 cross sections of Lake Maraetai during April 1995 (see Figures 1 to 4).
' a description of benthic community structure in water more tha¡ SO m deep at selected sites in Lake Maraetai during January 1gg6 (see Figures 2 and 3).
Lake Ma¡aetai is the fifth of eight hydro-electric lakes downstream of Lake Taupo on the Waikato River. It formed behind an 86 m high dam between 1952 and 1953. The Maraetai I powerhouse was commissioned in I9b2 and its penstock intakes are close to the lake surface. A second powerhouse, (Maraetai II) was completed at the Maraetai Dam in l97l and its penstock intakes a¡e in deep water.
The lake has an area of 4.2 kmz contained within a maximum length of 2.2 km and a maximum wÍdth of r.2 kilometres (viner tedJ, lggT). It has a maximum depth of 64.7 m (Irwin and van Kampen, f ggg) and an average depth of c 30 metres [Viner [ed], 1987). Lake level is at an altitude of g53 m (Viner [ed], 1987) or 188 metres above sea level relative to the Moturiki datum (Irwin and van Kampen, 1989). The centre of the lake is at a latitude of 4r's and a longitude of rr\' E (Irwin and van Kampen, Iggg).
Treated wastewater from the Kinleith Pulp and Paper Mill is discharged into Lake Maraetai via the Kopakorahi Stream. Kingett Mitchel & Associates (1995) report that between september l9g4 and February lgg5, Bl%o of flow g4 in the Kopakorahi Stream (mean of 365 + Ml..day-t) was sourced from Ûre wastewater treatment system at the Kinleith Milt. The Mill Discharge constituted some O.920/o of the total discharge of Waikato River water to Lake Waipapa during this same period.
Zuur (1989) reported that during 1988:
' the Kinleith discharge changed the colour of the Kopakorahi Arm of the lake and of the Waikato River to a measurable extent, and ' Kinleith effluent often did not disperse evenly as it mixed v/ith water in Lake Maraetai, but formed a plume that sank under lake water during summer and tended to flow over the top of lake water during the winter.
Brian T. Coffey and Associates Limited, Hamilton 5
Figure 1. lnca-lity sketch for Lake Maraetai showing locality of Tra¡rsects I - L2 (also see Figures 2, 3 and 4 for lake bathymetry)
NORTH ISLAND
L. Whakamaru 50 51 52 53 54
Map references per.: NZMS 260,T16'Tokoroa and NZMS 260,T17'Whakamaru
Meredith et al (1988) associated differences in the structure of animal communities in Lake Maraetai with the discharge of treated wastewater from the Kinleith Pulp and Paper Mill. Meredith et al (1988) also surveyed the Kopakorahi Stream upstream of Tlansect 8 (see Figure I).
Brian T. Coffey and Associates Limited, Hamilton Figure 2. Part of Lake Maraetai showing bath¡rmetry (after Irwin and van Kampen, 1989) between Transects I0 to L2. Deep water stations sampled at rransect L2 on os January, lgg6 are shown in white on black.
52 Grid references per NZMS 260 T16 Tokoroa and NZMS 260 rrr, whakamanr
Physical and chemical characters of the lake, together with a description of fish populations, were the subject of concurrent studies to descrÍbe receiving waters for treated wastewater from the Kinleith Pulp and paper Mill (the Kopakorahi Arm of Lake Maraetai).
Brjan T, Coffey and Associates Limited, Hamilton Figure 3 Part of Lake Maraetai showing bathymetry (after Irwin and van Kampen, 1989) between Transects 4 to 9. Deep water stations sampled at Site A, Transect 6A and 9 on OS January, Igg6 a¡e shown in white on black
þJ 54 55 Grid references per NZMS 260 T16 Tokoroa and NZMS 260rrr, whakamaru
Brian T. Coffey and Associates Limited, Hamilton Figure 4 Part of Lake Maraetai showing bathymetry (after Irv¿in and va¡r Kampen, 1989) between Transects I to 4.
52 s3
Grid references per NZMS 260 T16 Tokoroa and NZMS 260 TI7 , Whaka.maru
Brian T, Coffey and Associates Limited, Hamilton
10
The diver then inspected the lake bed in the vicinity of the lower depth limit of submerged macrophytes and swam direcuy to the shoreward marker recording the depth range, maximum height, average height, maximum cover class and average cover class of component macrophytes in each weed bed.
The dÍver assigned an overall cover score to periphyton at each site and representative samples were returned to the laboratory for identification.
6_IOOo/o) The boat was then positioned in the surface or near-surface canopy of submerged weed beds and a 25O micron mesh hand net was used to take five replicate sweeps through a I.O m x 0.4 m surface area section of the weed canopy to a depth of O.4 metres.
Plant and animal material retained in the net was preserved in isopropyl alcohol and returned to tlre laboratory for identification and counts of weed bed fauna' The relative abundance of water skaters at each site was estimated in the field and abundance estimates rather than counts we¡e recorded for purse caddis, mosquito larvae and sandfly larvae which were included in weed bed faunal samples.
3.1 Deep Benthos DescriptÍons, January 1996
An Ekman Birge dredge (sampling area of 15 cm x 15 cm) was used to collect five replicate samples of soft surficial sediments from selected deep- water sampring stations upstream and downstream of the Kopakorahi Arm in Lake Maraetai on 03 January 1996.
The boat was anchored in such a position relative to wind and cur¡ent that it could be ma¡roeuwed over the desired depth contour (with the aid of an echo sounder) at each time the dredge was lowered to the lake bed.
Five replicate samples were collected from a depth of 35 m at Transects b, 64, 9 and 12: five replicate samples were collected from a depth of 45 m at site A and rtansects g 64, and 12; and five replicate samples were collected from a depth of 55 m at rfansects g 6A, and t2 (see Figures 2 and B).
The 50 sediment samples were double-bagged on site and returned to the laboratory where they were sorted as fresh samples on 04 Jaauary 1996.
Brian T. Coffey and Associates Limited, Hamilton 11
sediment sample was smeared on a microscope r 4OO X magnification to identi$r the structure of des used for sediment type are as follows.
d / mud = diatomaceous mud
d / m.,.d /p = diatomaceous mud mixed wi*r a significant quantity of higher plant debris which did not pass a 250 p sieve
Notes were also made on plant material which did not pass through 25O¡t mesh. a
Macroscopic animars were sieved from each fresh sampre by an upward wash through a 25O ¡r stainless steel sieve.
Animals sieved from each sample were identifÍed and counted.
Voucher specimens (preserved in isopropyl alcohol) are available for each species / taxa recognised.
Brian T. Coffey and Associares Limited, Hamilton
13
Table 1. Provisional Species List: Lake Maraetai, April - May IggS
Common Name /Notes
Cyanobacteria Anabaena sp. Nostoc sp, Oscillatoria rubescens Oscillatoria spp. Schizothríx sp. Tt Algae Chlorella parasitica Cladophora glomerata diatoms - assorled, unidentified Enteromorpha nana var. minima ecad. rivularis Melosira sp. Microspora sp. Mougeotia sp. Oedogonium sp. Spirogyra sp. Vaucheria sp. Zvgnema sp. Bryophytes Drepanocladus aduncus moss Eurhynchium austrinum MOSS Fissidens rigidulus moss Hypnoden d ron m argi natu m moss Lunularia sp. liverwort (marginal - emergent species) Tridontium tasmanicum moss unindent. leafy liverwoñ Submerged macrophytes Ceratophyllum demersum hornwort Egeria densa egeria (oxygen weed) Elodea canadensis Canadian pond weed Lagarosiphon major lagarosiphon (oxygen weed) Myríophyllu m tr¡phyl I u m milfoil Nitella hookeri stonewort Free-floating specíes Azolla rubra azolla (water fern) Lemna minor duckweed Emergent / marginal macrophytes Anisotome aromalica herb Baumea rubiginosa rush Bidens frondosa begga/s ticks Bo lbosch oen us fl uvi atilis marsh clubrush Callitiche stagnalis starwort Cardamine pratensis lady's smock Carex geminata sedge Carex lambe¡liana sedge Carex secta niggerhead Cortaderia fulvida toetoe Crassula sinclairii herb Cyperus eragrostis umbrella sedge Elatine gratioloides herb Eleocharis pusilla "inter tidal" herb Epilobium sp. willow herbs Galium palustre marsh bedstraw Glossostigma diandrum "inter tidal' herb
Brian T. Coffey and Associates Limited, Hamilton t4
Table 1 continued Emergent / Marginal Species Common Name / Notes
Glyceria fluitans floating sweet grass lsolepis setacea rush Juncus acuminatus sharp-fruited rush Juncus a¡liculatus emergent rush; joínted Juncus effusus soft rush Juncus gregiflorus emergent rush Juncus prismatocarpus rush Juncus sp. rushes Lilaeopsis ruthiana herb Limosella lineata mudwo¡1 Ludwigia palustris water purslane Ludwigia peploides var montevidensis primrose willow Mentha spicata spearmint Mimulus guttatus monkey musk Myosotis laxa subsp. caespitosa water forget-me-not Myriophyllum votschii "inter tidal" herb Phormium tenax New Zealand flax Pinus radiata radiata pine Polygonum hydropiper water pepper Polygonum persicaria willow weed P o lygon um salicifoli u m swamp willow weed Pratia angulata panakenake Ranunculus amphitrichous waoriki Banunculus macropus swamp buttercup Ranunculus scleratus celery buttercup R o ri p p a n astu tli u m aq u atic u m watercress Salix sp. willows S ch o e no pl ectu s val i d u s lake clubrush Typha orientalis bullrush
Platyhelminths Cura flatworm Hirundinea multistriata leech Oligochaeta unident. tubificids Coelenterata
kakahuensis Crustacea P araneph ro ps planifro'ns freshwater crayfish unident, amphipods unident. ostracods Mollusca Gyraulus corinna snail Hyridella menziesi freshwater mussel Lymnaea tomentosa snail Physa acuta snail Planorbarius corneus snail P otamopyrgus antipodaru m snail Sphae riu m novaezelandiae pea mussel
Brian T. Coffey and Associates Limited, Hamilron 15
P otamopyrgus antipodaru m snail Sphaeri um novaezelandiae pea mussel
Table 1 conlinued Common Name / Notes
lnsecta Anisops wakefieldi backswimmer Au stros im u li um ti llyardian u m sandfly larvae Chironomus sp. midge larvae Culex pervigilans. mosquito larvae Homeodytes hookeri water beetle Hygraula nitens aquatic moth larvae Microvelia macgregori water skater Oxyethira albiceps larval purse caddis P aroxy eth i ra h e nd e rs o n i larval purse caddis Procordulia grayi dragonfly larvae Rhantus pulverosus beetle larvae Xanthocnemis larvae Fish* Carassius auratus goldfish G obiomo rph us cotidia nus common bully Retropinna retropinna smelt Scardinius dd Bírds Anas supercÌliosa Grey Duck Anus platyrhynchos Mallard Duck Cygnus atratus Black Swan P h al ac roc o rax m elan o l e u cos b rev i ro st ris * Brown trout (Salmo tnrtta) and rainbo'\¡¡ trout (Oncorhgrrchus mykrss) also laeown to be present.
Figure 5 Stylised Profile for Tl 0
10
20 Water Depth 39 (m) 40 IillJLifli'., no visibilitv 50 in ambient'light remains of submerged trees
Distance along water surface from Left Bank (m)
Brian T. Coffey and Associates Limited, Hamilton r6
Figure 6 Stylised Profile for'12
0
.t0
20 Water Depth 39 (m) 40 r;."'iL';fli'., no visibililv 50 in ambient'light remains of submerged kees 100 200
Distance along water surface from Left Bank (m)
Figure 7 Stylised Profile for T3 0
10
20 Water Depth 39 (m) submerged 40 macrophytes no visibilitv '50 in ambient'light remains of submerged trees 100 200 Distance along water surface from Left Bank (m)
Figure 8 Stylised Profìle for T4 0
10
20 Water Depth 39 (m) 40 I;,i'Jl,ifff,, no visibility 50 in ambient light remains of submerged trees 100 200 300 400
Distance along water surface from Left Bank (m)
Brian T. Coffey and Associares Limited, Hamilton 17
Figure 9 Stylised profile for T5 0
10
20 Water Depth 39 (m) 40 I x.'¿1,iff^i, 50 f í1,'.iliß,jlll,nn, remains of submerged trees 200 300 400
Distance along water surface from Left Bank (m)
Figure I0 Stylised Profile for T 6A 0
10
20 Water Depth 39 (m) 40
50
ruu 400 500 600
Distance along water surface from Left Bank (m)
Figure l l Stylised Profile for T 68 0
10
20 Water Depth 39 (m) 40 r#ii.iflii, 50 f í],'*,î,llllT,nn,
100 200 400 500
Distance along water sudace from Left Bank (m)
Brian T. Coffey and Associates Limited, Hamilton 18
Figure 12 Stylised Profile for T 6C 0
10
20 Water Depth 39 (m) 40 f ;iåi,ifli',, 50 f ß'.Hïß'JllT,nn, llllllllllll nr; l¿B!u,., 100
Distance along water su¡face from Left Bank (m)
Figure 13 Stylised Profile for T7
0
't0
20 Water Depth 39 (m) 40 r;1.nifli", 50 f ír,Ilißlllln'',
100 200 Distance along water surface from Left Bank (m)
Figure 14 Stylised Profile for T gA 0
10
20 Water Depth 39 (m) 40 f ;,'.t#.iff^'., 50 I fi',ili,oJillT,nn,
llllllllllll :',må:!,",, 100 200
Distance along water sudace from Left Bank (m)
Brian T. Coffey and Associates Limited, Hamilton t9
Figure 15 Stylised Profile for T 88 0
10
20 Water Depth 39 (m) 40 rilfJffJfli,,, no visibility 50 in ambient light remains of submerged trees
Distance along water surface from Left Bank (m)
Figure 16 Stylised Profile for TO9 0
10
20 Water Depth 39 (m) submerged 40 macrophyles no visibilitv 50 in ambient'light remains of submerged trees 100 200 300 400 500
Distance along water surface from Left Bank (m)
Figure 17 Stylised Profìle for TlO 0
10
20 Water Depth 36 (m) 40 Ii'á'Jl,Jffi",, no visibility 50 in ambient light remains of submerged trees
Distance along water sudace from Left Bank (m)
Brian T. Coffey and Associares Limited, Hamilton 20
Figure I8 Stylised Profile for TI I
Transect 1 1
20 Water Depth 39 (m) 40 I;i,'ii.ïfi", 50 f l},'*,i,?i]lT,nn,
lllllllllll :',rru¿:!,,,,, 100
Distance along water sudace from Left Bank (m)
Figure 19 Stylised Profile for TI2
20 Water Depth 3q (m) 40 r;,'.'Jiöfli", no visibilitv 50 in ambient'light remains of submerged trees 100 200 Distance along water surface from Left Bank (m)
Notwithstanding Transect 68, chart recording echo-soundings for Transects I to 10 reconciled well with the bathometric chart produced by irwin ald van Kampen (1989).
The transect of Tlansect 6 B (see Figure 11) Oi¿ not coincide with a transect sounded by Irwin and van Kampen (IgBg). There is a central area of sha-llows in the centre of Transect 68 which supports a surface - reaching bed of CeratophgLLum demersum.
Brian T. Coffey and Associates Limited, Hamilton 2t
Table 2 Distribution records for aquatic macroph5rtes, weed bed fauna and benthos at rransects L - 12, Lake Maraetai, IggS - 1996 where p = present
Egeria densa EIodea canadensis Lagarosiphon major My riophyl lun t i phy I I u m
Eurhynchium austrinum Fissidens rigidulus
Hy p nod e nd ro n n ar gi n atu m Tridontiun tasmanicum unindent. leafv liverwort
cyanobacteria Anabaena sp, Oscil latoria rube sce ns Oscillatoria spp. Schizothrix sp. T
assorled Melosira green Chlorella parasitica Cla;dophora glonerata Enleromorpha nana Microspora sp. Mougeotia sp. Oedogonium sp. Spirogyra sp. Vaucheria sp.
Elatine gratioloides Eleocharis pusilla Glossosligma diandrun Lilaeopsis ruthiana Limosella lineata Myriophyllum volschii Pratia angulala
Brian T. Coffey and Associates Limited, Hamilton 22
Table 2 continued
P aranephrops planif rons amphipods ostr
Gyraulus corinna Hyridella menziesi Lynnaea tonentosa Physa acuta Planorbarius corneus Potamopyrgus antipodarum iun novaezelandiae
Anisops wakefieldi Austrosimulium tillyard. Chirononus zelandicus Culex peruigilans. Honeodytes hookeri Hygraula nitens Microvelia macgregori Oxyethira albiceps P aroxyethira hende rsoni Procordulia grayi Rhanlus pulverosus Xanthocnemis zelandica
Carassius auratus G obi omo rph u s coti di anu s Retropinna retropinna Scardinius
Brian T. Coffey and Associates Limited, Hamilton 23
Figure 20 Relationship between the lower depth limit of submerged macrophytes and provenance in Lake Maraetai, April lgg5.
V =7.0667 - 0.36667x R^2 = O.gg9 Lower Depth limit (m)
TI T2 T4 T5 T6 T7 T8 T9 TIO TII T12 Transect
Figure 2l Covei class estimates for perÍphyton at a depth of 12 m. T1 _ T12, April 1995.
tr Left Bank o Right Bank
Peripþyton cover class estimates @ 12 m depth
5 6A686C 7 8A 8B
Transect Number
Brian T. Coffey and Associates Limited, Hamilton 24
Figure 22 Mean population estimates for amphipods in the canopy of submerged macrophytes, Tfansects 1 _ 12 (¡=g)
Key tr Left Bank o Right Bank (Standard Deviation)
mean count per 0.16 cu. m (353.4) E
(5.20) (6,s0) (5.4r) (e.58) (3.65) (z,f;ll) (4.02) p.os¡l2o;n) (3.e4) (1.82) (4,43) (1 .73) (1,34) (1.e2) t13.5e) (1.73) '' ' .. ' (4.441 'ä {trze) ,t.ro, T2 T3 T4 T5 T6A T68 T6C W T8A T8B T9 rìO rII T12 Locality
Figure 23 Mearr population phgsa estimates ror acuta in the canopy of submerged macrophytes, Transects I _ 12 (n=5)
(310.3) (sso.9) Key E¡r tr Left Bank ? Right Bank (Standard Deviation)
mean 200 count per 0,16 cu. m
149.68) ise.ezÍ W'17) (4.s0) (5.17) (s.$) (3.58) (4.82) (7.35)'B'(10.34) o (2.70) (5.72) (t,57) (1.00) (s.s6) (1.22) (3,58) I T1 T2 T3 T4 T5 T6A T68 T6C T7 T8A T8B T9 T1O T11 T12
Locality
Brian T. Coffey and Associates Limited, Hamilton 25
Figure 24 Mean population estimates for PLanorbørúus corrLeu.s in the canopy of submerged macrophytes, Transects L - 12 (n=5)
Key tr Left Bank . Right Bank (Standard Deviation)
(3.58) tr
(1.87) (3.s4) o O mean count per 0.16 cu. m
(1.22) o (0.84) (1,30) (0.5s) E (o.ss) tr (0.8e) o E¡ tr (0.44) (0.44) (0.44) (0.44) (0.44) (0.44) o rto o o o'
T6A T68 T6C T1 T8A T8B T9 T1O T1.I T12 Locality
Figure 25 Mean population estimates for potamopargus antipodarum in the canopy of submerged macrophytes, Tfansects L - rz (n=b)
(1se.05) tr Key tr Left Bank o Right Bank (Standard Deviation) 60
mean count per 0.16 cu. m.
{51.66)'o'
(7.33) g'33) (7.04) o to.eal (%o) tr (5,61) trE tu,rrl (1,64) (1 tr (0,44) (1,s0) (1,41) -12 T1 T3 14 T5 T6A T68 T6C T7 T8A T8B T9 T10 T11 T12 Locality
Brian T. Coffey and Associates Limited, Hamilton 26
Figure 26 Mean populatÍon estimates for Xanthocnemís zeLartdica. tn the canopy of submerged macrophytes, Transects L - 12 (n=5)
15 Key (10.50) E Left Bank 'Et' o Right Bank 18.82) 'tr' (Standard Deviation) (e,15) tr
(3,83)'a (581)tsy)t6.a3l
mean count per (8.00) 16.06)' E' 0.16 cu. m " '''30'(T6)(536)
(1.00) (1.30) o (0.55) o
T3 T4 T5 T6A T68 T6C T7 T8A T8B T9 T1O T11 T.12 Locality
Fígure 27 Mean population estimates for tubificids at a depth of 12 rn, Transects L - L2 (n=5)
Key tr Left Bank o Right Bank (Standard Deviation)
mean 400 count per 0.0225 sq.m 300
(5.36) (0.8e) (8.47) (8,44) (1,00) (455) (2s5) (zfo) (1.0+l (3'85)(1T8) 11.64 'g' 'üi'1'tl:tì
Ï1 12 T3 T4 T5 T6A T68 T7 T8A T8B T9 T1O T11 T12 Locality
Brian T. Coffey and Associates Limited, Hamilton 27
Figure 28 Y.ry population estimates for PotamopArgus antipodarum at a depth of 12 m, Transects 1 - 12 (n=5)
Key tr Left Bank
(s,13) o Right Bank EI (Standard Deviation)
mean count per 0.16 cu. m
(3.13) a
tr (1.30)
T1 T2 IJ T4 T6A T68 T6C T7 T8A T8B ï9 T10 T11 T12 Locality
Figure 29 Mean population estimates for sphaeriumnouaezetandíae at a depth of L2 m, Tlansects I - 12 (n=5)
Key tr Left Bank o R¡ght Bank (Standard Deviation) 6
mean count per 0.0225 4 sq,m
(1 .30) t1.30ì tr 'o' (1.34) (3,74) (0.8E 10.55) tr (0.8e) (0.8e) (0.8s) tr 'o' o O tr o
T1 T5 T6A T68 17 T8A T8B T9 T1O T11 T12 Locality
Brian T. Coffey and Associates Limited, Hamilron 28
Figure 30 Mean population estimates for chíronomus zelandicus at a depth of 12 m, Tfansects I - 12 (n=5)
Key tr Left Bank 17.56)'o' . Right Bank (Standard Deviation)
mean count per 0.0225 13.35t'o' sq.m
(3,64 o
(2.s1) E (2,41) (2.6r) (2.1e) o (3,08) tr tro (1,52\ tr (2.1Ð E' tzsn . (1.41) (tjo) (0.84) ¡.s+¡ tr tr (0.55) a
T2 T3 T4 T5 T68 T6C T7 T8A T8B T9 T1O T11 T12 Locality
Figure 3l population estimates for tubificids at a depth of 25 m, Ttansectsl-12(n=5)Y"*
(223.1) Key o Left Bank o Fìight Bank (Standard Deviation)
80 r¡ean count per
0.0225 . 60 sq.m
(t3jo)(o,r¿) (B,Bs) . T68 .88 (6,46)(13n11166) " tti*rruîa(!4 qo <25 m deep (5)40)
T1 T2 T3 T4 T5 T6A T9 T10 T11 T12 Locality
Brian T. Coffey and Associates Limited, Hamilton 29
Figure 32 population Y"T estimates ror spha.eriumnouazeLandine at a depth of 25 m, Tlansects I - 12 [n=5)
(3.74) Key tr tr Left Bank o Right Bank (Standard Deviation)
mean count per 0.0225 sq.m
(0.8s) (0.8e) (0,8e) tro tr ).441 E T68 - 8B tr (0.8s) <25 m deep
T1 T2 T3 T4 T5 T6A T9 T10 I11 T12 Locality
Figure 33 Y.* pgpulation estimates for chí¡onomus zera¡tdiats at a depth of 25 m, Transects I - 12 (n=5)
Key tr Left Bank o Right Bank (Standard Deviation)
mean count per 0.Q225 sq.m (2,68) tr (2.16) tr (1.64) o tr (1.41)
T10 T11 T12 Locality
Brian T. Coffey and Associares Limited, Hamilton 30
Figure 34 A comparison of mean population estimates for benthos at the 35, 45 and 55 m depth contours at sampling stations Site A, Transect 5, Transect 6A Transect 9 and Transect 12.
#t- Chironomuszelandicus s.D. 8.33 50 ----+--- worms
40
30
20
10 s,D.12.72 s,D. 1.67 0 T6A T9 T12
50
40 Population counts per 30 15cmx15cm 20
l0
0 T12
50
40
30
20
10
0 T6A T12
Locality
Brian T. Coffey and Associates Limited, Hamilton 31
Figure 35 A comparison of mean population estimates for bentl:os at Transects 6,4', I and 12 in relation to water depth
A worms ø Chironomus zelandicus s.0.3,57
s.D,7.13 s.D.4.04
Transect 6A
s.D, 1.30 35m s.D, 1.30
water s,D,2,86 45m depth s.D.2.86 (m)
s.D,3.85 55m s.D. 3.85 Transect
10
s.D.12.72
s.D. 1.67
s.D. 6.50
s.D,2,86
s.D.2,17 s,D,3.42 Transect 12
10 15 20
population counts per 15 cm x 15 cm
Brian T. Coffey and Associates Limited, Hamilton 32
Figure 36 Tfend analysis for worm counts at a depth of 45 m at Site A, Tfansect 64, Transect 9 and Transect 12. 50
Site A
Arm
population count for worms per 15cmx15cm (n=5)
v = 33.413 ' 10 (-2.5837e-4x) R^2 = 9.699
1000 2000 3000 4000 Distance downstream from site A (m)
Figure 37 Trend analysis for chironomid counts at a depth of 45 m at Site A, Transect 64, Transect 9 and Transect 12. 25. Kopakarahi Arm T6A
population Site A co,unt for worms per Y = 18.170 - 2.9313e-3x R^2 = 9.654 15 cm x '15 cm (n=s)
T12
1 000 2000 3000 4000 Distance downstream from Site A (m)
Brian T. Coffey and Associates Limited, Hamilton 33
5.O Discussion of Results
5.1 The light climate in Lake Ma¡aetai
ceratophglLum demersum was recorded as a dominant submerged macroph5rte (see at all transects Table 2). Egeria d.ensa was recorded at all tra¡rsects except Transect 88. These two introduced species are common Ín relatively turbid and eutrophic waters elsewhere in New Zealand, including t].e waikato hydro lakes from Lake ohakuri to Lake Karapiro.
ELodea cana.densis, MyriophgLLum triphglLum and lViteü a hookeri were not recorded at transects downstream of Transect 5 or 6. Elsewhere in New ZeaJand these species are generally associated with more transparent water than eitlrer Egeria or Ceratophyllwrt
This distribution pattern for submerged macrophytes is consistent with water in the upstream section of Lake Ma¡aetai (Transects I - 5) being more transparent tl:an water in the downstream section of the lake (Transects 9 to t2).
This trend is also supported by the reduced depth range of submerged macrophytes in the downstream section of the lake relative to upstream sites (see Figure 20) and the reduced cover of epipelic periphyton on the lake bed at a depth of L2 m in t].e downstream section of the lake (see Figure 2I).
The average depth range of submerged weed beds between Tra¡rsect I and Transect 5 was in the order of 6 metres, The average depth range of submerged g weed beds between Transect and Transect 12 was in the order (see of 3.5 metres Figure 20). The area of the lake between Transect 9 and Transect 12 was in the order of rr2 ha and the area between the o _ Io m depth contours was in the order of 34 hecta¡es. Assuming an even gradient between 0 - 6 m depth contours in the lake between Transect g and Transect 12, weed'beds with a depth range of 1 - 6 mwould occupy Ig.7 hecta¡es. weed beds with a depth range of I - 3.5 mwould occupy onry 45o/o of this a¡ea which is 8.5 hectares.
The effect of decreased water clarity in the downstream section of Lake Maraetai appears therefore to have a significant effect on the area occupied on submerged macrophytes.
The most restricted depth range for submerged macrophytes was recorded in the Kopakorahi Arm of Lake Maraetai which suggested that water in this
Brian T. Coffey and Associates Limited, Hamilton 34
arm of the lake was generally tess transparent than in the main lake (Figure 20).
In-water visibility was generally compromised in tJ:e downstream section of the lake compared to its headwaters (see Figures 5 to I9). There was adequate ambient lighting to work to a depth of 20 m at Transects I to 4 during April 1995. At Transects tO to 12, arLificial lights were requi¡ed to work below I5 m depth.
These findings a¡e consÍstent with the report of Zuur (1989) who reported that water in the Kopakorahi Arm of Lake Maraetai was measurably more highly coloured than the main lake due to the discharge of kraft mill effluent.
Another factor which may contribute to a reduced depth of the photic zone in the downstream section of Lake Maraetai is an increase of phytopla¡lkton standing crop as water moves through the lake (an impoundment effect). Incremental nutrient inputs to Waikato River water within Lake Maraetai might be expected from tributaries draining agricultural land, silt inputs from milled exotic forests, mineralisation of kraft mill efÍIuent and sewage discharges from the township of Mangakino.
6.2 Dist'ribution of bÍological indícators of water quatity in Lake Maraetai
Surveys summarised in this repor[ involved a sampling strategr rather than total-coverage of the lake bed. on this basis, only presence records are significant and it is not implied that species which were not recorded in a particular section of the lake were not present.
However'submerged bryophytes (mosses and liverworts) were only recorded in the upstream section of Lake Maraetai (Table 2) despite the presence of rock outcrops on'the littoral zone at both Transects II a¡rd 12 (see Table 4 (Appendix). These species are generally best developed as epilithic growths (on rocþ substrata) in relatively transparent flowing water. They are the dominant vegetation type in the upper Waikato River from the Taupo Gates to the Huka Falls and in the taÍlrace of the Aratiatia Power Station for example. However they are also a feature of the Arapuni and Karapiro tailrace where water is generally turbid and relatively highly coloured.
Brian T. Coffey and Associates Limited, Hamilton 35
Algae and cyanobacteria which are generally assocÍated with wastewater dÍscharges elsewhere in New Zealand (vÍs. Anabaena. sp., Schizothríx spp. ToLypothrix spp., and CLadophoragLomeratø) were only recorded as present Ín the Kopakorah.i Arm and the downst¡eam section of the lake (see Tabie 2).
The leech Gtossþhonia muLtistriata was only recorded in the upstream section of the lake, as was t}:.e bryozoa¡r PlumateLLa repens (see Table 2) Suitable substrata was present for PLumøteILa in the downstream section of tl.e lake (submerged wood and rock).
In terms of weed bed fauna, the snails Lgmnaea tomentosa and Ggrauhs cortnnawere only recorded in the upstream section of the lake (see Table 2). Potamopyrgus antipodarum was most common and locally abundant in the upstream sectÍon of the lake (see Figure 25),
Weed bed fauna which were most frequent or locally abundant in the Kopakorahi .{rm of Lake Maraetai during Aprit 1995 included amphipods (see Figure 22) and Phgsa acuta (see Figure 2g). Sandfly larvae (,Austrosimulíum tíLlgardiønum) were only recorded in weed beds within the Kopakorahi Arm (see Table 2). other members of the weed bed fauna (e.9. pLanorbarius corneus and Xanthocnemis zeLandica) occurred throughout the lake including the Kopakorahi Arm (see Figures 24 and 26).
The wide range of variability in replicate samples for weed bed fauna (see Table 6 - Appendix and Figures 22 - 26) may have been associated with the mixed assemblage of macrophyte canopies sampled. In general, ceratophyLLum demersum appeared to support a lower diversity and abundance of weed bed fauna than did Egeriadensa.
5.3 Trend Analyses for deep-water benthos
Macrobenthos such as the freshwater mussel HgrideLLa mertziesi and the freshwater crayfish Paranephrops planlfrons were present on stable sand or sandy-mud which was generally restricted to areas influenced by water currents.
Elsewhere between water depths of 12lo 25 m, mud in deposÍtional areas on the lakebed was typically "fluid' and poorly compacted. Benthic
i Brian T. Coffey and Associates I Limited, Hamilton I 36 communities on and in these muddy substrata Íncluded tubificid worms, chÍ¡onomid larvae, ost¡acods and pea mussels.
The hÍghest individual replicate counts for tubÍficids at a depth of 18 m were recorded at Transect I (see Figure 27). This was also the case for the pea mussel Sphaertum nouaezeLandiae (see Figure 29) and larvae of the non- biting midge Chvonomts zeLandicus (see Figure 30).
At a depth of 25 m, the highest replicate counts for tubificids occurred at Transect lO (see Figure 31). Similarly, the highest replicate counts for pea mussels a¡:d Ch¿ronomus zeLandicus occurred in the downstream section of the lake (see Figures 32 a¡d 33) although it should be noted that Transects 68 to 88 were less than 25 m deep.
Oniy two taxa were important components of deep water benthos between Site A (see Figure 3) and TTansect 12 (see Figure 2) during Janua:y f 996. These were tubificid worms and Chironomus zelandicus. Occasional flat worrns were associated with deep-water benthos at Site A, Transect 5 and Transect 6A (see Table 7 - Appendix).
The dominant component of surficial, deep-water, sediments deposited in the old river channel at depths of 35 to 60 m was plankton debris, dominated by frustules of chain-forming species of the diatom MeLosira.
There appeared to be a progressive decline in the mean abundance of chi¡onomid larvae and worms in deep-water benthic communities between site A and rransect 12 (see Figures 36 and 37) but this trend was only significant for tubifìcids (* = 0.898).
It was of Ínterest that Judd et al. (I995) reported elevated concentrations of chlorophenolic compounds and resin acids in sediments of the V/aikato River downstream of the Kinleith discharge and that shallow surficÍal sediments contain the majority of organic contaminants.
At Transects 6A alrd 9, the mean abundance of benthos appea-red to be less at 35 m depth than at 45 and 55 m depth (see Figure 55). These differences were not statistically significant but it did appear sediments at 35 m depth at these sites generally included a higher component of refractory plant matter of terrestrial origin (see Table 7 - Appendix).
The presence of terrestrial plant debris in shallower sediments but not in the main river channel suggests that deep water currents in the lake prevent
Brian T. Coffey and Associates Limited, Hamilton 37
other than heavier diatom debris being incorporated into the deepest lakebed sediments.
Hickey and Martin (Ì995) investigated the relative sensitÍvit5r of five species of New Zealand aquatic invertebrates to reference toxicants and sediments contaminated by resin acids. These data relate to the surr¡ival of species (includÍng the worm Lumbriculus uariegatus) in relation to short term exposure to toxicants (acute toxicity studies). Hickey and Martin (1g95) consider the development of sublethal toxicity tests for worms have promise in terms of assessing the effects of wastewater discharges containing bleached kra-ft mill effluent.
The mixing patterns of water entering Lake Maraetai from the Kopakorahi Arm are clearly complex and related to season (Zuur, rggg) and local weather conditions. It appeared likely from data presented by zuur (lggg) (which that Transect 6A was technically upstream of the Kopakorahi A¡m) may also be influenced by discharges into the Kopakorahi Arm from the Kinleith Pulp and Paper Mill.
6.0 Conclusions
Three differences in the structure of resÍdent, submerged, macrophyte and invertebrate communities have been Ídentified between the upstream and downstream sections of Lake Ma¡aetai.
The depth of the photic zo¡re for submerged macrophytes and epipelic periphyton in the downstream section of Lake Maraetai is reduced relative to the upstream section of the lake. Whilst the downstream section of the lake is deeper and steeper-sided, a diving inspection of the lower depth limit of submerged macrophytes suggested that it was water depth rather than súbstrate type or substrate stability which was associated with the lower depth limit of submerged macrophytes between Transects 9 a¡d 12.
There is an increased frequency / abundance of "pollution indicators', in the downstream section of the Lake Maraetai including the Kopakorahi Arm of ttre lake.
There is a reduced abundance of deep water benthos in the downstream section of the lake. However it is noted that a viable benthic community was present throughout the deepest mainstream channel of the lake during January 1996.
Brian T. Coffey and Associares Limited, Hamilton 38
The extent to which these differences in submerged community structure ca¡r be associated with the discharge of bleached kraft miil effluent from the Kinleith Mill to the Kopakorahi Arm of Lake Maraetai wÍll depend on the findings of complementary studies on physical and chemical characterÍstics of the lake a¡ld fisheries studies. These collective data are to be collated and reported on by Kingett Mitchell and Associates Limited.
7.O References
Brian T. coffey and Associates Limited, lg95: Lake Ma¡aetai - Middle Waikato River. A contribution to a biological resource inventory for resident, submerged, macro-organisms. Ref.: BBRI / L. Maraetai C,H.H., September 1g95. Areport prepa:-ed for Carter Holt Harvev, private Baq, Tokoroa.
Brian T. coffey a¡rd Associates Limited, 19g6: supplementary comments and Studies on Lake Ma¡aetai - Middle Waikato River. A contribution to a biologÍcal resource inventory for resident, submerged, macro- organisms. Ref.: BBRI L. Maraetai / 02 c.H.H,, Jan 1996. A report p¡epa¡ed for Carter Holt Harvey, private Bag, Tokoroa.
Hickey, c.\M. and Martin, M.L., rg95: Relative sensitivity of five benthic invertebrate species to reference toxicants and resin-acid contaminated sediments. Environmental T and C Vol. 14, No. I L40L- r 409. o73O-7268(95)00080_ r
(1986) Hoa¡e, R. A. Monitoring of water rights and discharges of N.Z. Forest Products Company, Kinleith. Hamilton ' Waikato Vallev Authoritv Technical Report lgg6/22.
Irwin, J,, van Kampen, J., IgBg: Lake Maraetai Bathymetry 1:10,000 New Zealand Oceanographic Jnstitute Chart, Lake Series
Judd, M,c., stuthridge, T.R., Tavendale, M.H., McFarla¡re, p.N. Mackie, K.L., Bucldand, S.J., RandaII, C.J., Hickey, C.W., Roper, D.S., Anderson, s.M. and stewart, D. I995: Breached Kra-ft putp Mili sources organic chemicals in sediments from New Zealand rivers. Part l: Waikato River.
pp 175I -1765.
Brian T. Coffey and Associates Limited, Hamilron 39
Kingett Mitchell & Associates Limited, I995: Kinleith Mill receiving waters Physical and chemical study 1994-95, Draft Prepared for Technical Working Group, Kingett Mitchell & Associates Ltd., March 1995
Meredith,4.S., and Davenport, M.W. (1988) Effects of pulp and paper effluent on invertebrate communities of the Kopakorahi Streams catchment. Waikato Catchment Board Technical Report 1988/ 12. 17 pp.
Meredith, 4.S., Davenport, M.W. and Scrimgeour, G.J., tgBS: NZ Forest Products, Kinleith Mill Investigations. Effects of pulp and paper mill effluent on macroinvertebrate and fish communities in Lake Maraetai. Waikato Catchment Board Technicai Report 1988/5, InvestiAations Unit, Waikato Catchment Board, P.O. Box 4OI0, Hamilton East, August 1988.
' Viner, A.B. (ed), 1987: Inland Waters of New Z¡-aland. D.S.I.R. Information Publishing Centres, P.O. Box 9741 Wellington. D.S.I.R. Bulletin ISSN 007-96IX, 24I, ISBN 0-477 -06799-9.
Zuur, Bob, 1989: NZ Forest Products Kinleith Mill lnvestigations. The mixing of Kinleith kraft effluent in Lake Maraetai Waikato Catchment Board Technical Report Ig89 / 28.
Brian T. Coffey and Associates Limited, Hamilton Appendix - Tabulated Survey Data
Brian T. Coffey and Associates Limited, Hamilton. Table 3 Submerged macroph5rte data for Tra¡rsects I to 12 (mud - muddy-sand substrata between 2 - 6 m at all sites)
Ceratophyllum demersum Left Bank upper depth limit (m) 0.8 0.8 o.4 0.3 't.0 1.0 0.4 1.0 1.0 1.5 2.O 0.6 1.5 1.0 0.8 lowerdepth limit (m) 6.5 5.5 6.0 5.5 6.0 5.5 4.O 4.O 4.0 2.O 2.5 4.0 4.5 3-0 3.5 maximum height (m) 3.0 4.O 3.5 3.0 3.5 3.0 3.0 3.0 1.5 0.8 2.O 3.0 2.0 2.5 2-O average height (m) 2.0 2.5 2.5 2.5 2.5 2.5 2-0 2.O 1.0 0.8 1.0 2.O 1.5 2.O 2.O maximum cover class 6 6 6 6 6 6 5 5 5 2 3 5 4 6 4 average cover class 4 3 4 5 4 4 l) 3 3 I 1 3 2 4 Right Bank 3 upper depth limit (m) 0.5 1.0 1.0 0.8 0.6 1.0 1.0 1.5 0.6 0.5 1.0 1.0 0.6 0.5 1.5 lower depth limit (m) 6.0 6.0 5.5 6.0 5.0 3.0 3.0 4.5 3.0 2.O 1.5 3_5 3.5 4.O 3.5 maximum height (m) 3.0 3.0 3.0 3.5 3.0 2.5 2.5 2.O 1.5 1.0 1.0 2.O 2.5 2.5 3.0 average height (m) 1.5 2.5 2.0 2.5 2.O 1.5 1.5 1.0 1.0 1.0 1.0 1.5 2.O 2.0 maximum cover class 6 1.5 6 6 6 6 4 4 5 4 5 3 4 avefaqe 5 3 6 cover class 5 5 5 5 3 3 '1 3 2 2 1 2 2 3 Egeria densa 3 Left Bank upper depth limit (m) 0.6 0.8 0.5 0.5 0.6 1.0 't.0 1.0 0.8 0.6 1.0 1.5 0.8 lower depth limit (m) 3.5 6.0 4.5 4.0 4.5 4.5 3.5 3.5 3.5 4.O 3.5 3.0 2.5 maximum height (m) 3.5 3.5 3.5 2.5 3.0 3.0 2.5 2.5 1.5 2.5 2.5 2.O 2.O average height (m) 1.5 2.O 2.0 1.5 2.O 2.0 1.0 1.0 1.0 1.5 2.O 1.5 1.0 maximum cover class 6 6 6 6 6 5 4 4 2 5 4 4 5 average cover class 2 !) 3 2 4 3 1 1 1 3 Right Bank 2 2 1 upper depth limit (m) 0.5 0.6 1.0 1.0 0.6 0.6 0.6 2.0 1.0 0.8 lower 0.8 0.8 1.0 1.0 depth limit (m) 5.5 5.0 5.0 5.0 5.0 3.0 3.0 3.0 3.5 1.5 3.5 2.5 3.0 4.0 maximum height (m) 3.0 3.0 3.0 3.0 2.5 1.5 1.5 2.0 2-O 1.0 2.O 2.5 average height (m) 2.0 2.5 2.5 2.5 2.0 2.0 2.0 1.0 1.0 1.0 '1.5 0.5 maximum 1.5 1.0 2.0 2.O cover class 6 6 6 4 6 J 3 4 5 3 4 5 4 cover class 1 1 5 2 1 2 1 1 1 1 1 2 2 2 2
Brian T. Coffey and Associares Limited, Hamilton. lll
Table 3 continued
T1 T2 T3 T5 T6A T68 T6C I T7 T8A T8B T9 lT10 T11 T12 Elodea canadensis Left Bank upper depth limit (m) 1.5 lowerdepth limit (m) 2.O maximum height (m) 1.5 average height (m) 1.5 maximum cover class 2 average cover class 1 Right Bank upper depth limit (m) 2.O 1.0 1.0 lower depth limit (m) 2.O 2.5 1.0 maximum height (m) 1.5 2.O 0.5 '1.5 average height (m) 1.5 0.5
maximum cover class 4 3 1
cover class 1 1 1 Lagarosiphon major Left Bank upper depth limit (m) 1.0 2.O lower depth limit (m) 1.5 2.O maximum height (m) 1.0 2.O average height (m) 0.8 2.0 maximum cover class 2 1 average cover class 1 1 Right Bank upper depth limit (m) 2.O 2.0 0.8 lower depth limit (m) 3.0 2.5 1.5 maximum height (m) 2.5 2.0 1.0 average height (m) 2.O 1.5 1.0 maximum cover class 2 5 1 cover class 1 2 1
Brian T. Coffey and Associates Limited, Hamilton. lv
Table 3 continued
T1 T3 f4 T5 T5A T68 T6C 17 18A T88 T9 T10 T11 T12 Myriophyllum tríphyllum Left Bank upper depth limit (m) 0.3 lower depth limit (m) 1.0 max¡mum height (m) 0.4 average height (m) o.2
maximum cover class 1
average cover class 1 Right Bank upper depth limit (m) lower depth limit (m) maximum height (m) average height (m) maximum cover class cover class Nitella hookeri Left Bank upper depth limit (m) 6.0 0.4 5.5 5.5 3.0 lowerdepth limit (m) 6.0 6.5 5.5 6.0 4.O maximum height (m) 0.1 0.2 o.2 o.2 0.1 average height (m) 0.1 0.1 o.2 o.2 6 maximum cover class 3 6 2 6 1 average cover class 1 1 1 4 Right Bank upper depth limit (m) 5.0 0.5 lower depth limit (m) 5.5 0.5 maximum height (m) o.2 0.1 average height (m) 0.1 0.1
maximum cover class 6 1
class 2 1
Brian T. Coffey and Associates Limited, Hamilton. Table 4 Periphyton data for Transects TI to TIO
Anabaena sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Chlorella parasitica Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Cladophora glomerata Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Brian T. Coffey and Associates Limited, Hamilton. vi
Table 4 continued
T1 T2 T3 T4 T5 T6A T68 T6C T7 T8A T8B T9 T10 T11 T12
diatoms - assofted, Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Drepanocladus aduncus Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Enteromorpha nana Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy at'12 m Eurhynchium austrinum Left Bank macrophyte canopy at 12 m depth Fìight Bank macrophyte canopy al 12m
Brian T. Coffey and Associates Limited, Hamilton. vii
Table 4 continued
T1 T2 T3 Í4 T5 IT6A T68 T6C I T7 T8A T88 T9 T10 T11 I T12
Fissidens rigidulus Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Hyp nodend ro n marg¡ natu m Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Melosira sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Microspora sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Brian T. Coffey and Associates Limited, Hamilton. vlll
Table 4 cont¡nued
Mougeotia sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy at12m Oedogonium sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy at12m Osci llato ria rubesce ns Left Bank macrophyte canopy . aI 12 m depth Right Bank macrophyte canopy at12m Oscillatoria spp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy aI12m
Brian T. Coffey and Associates Limited, Ham.ilton. IX
Table 4 continued
T1 12 T3 r4 T5 T6A T6B T6C 17 T8A T8B T9 T10lT11lT12
Schizothrix sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Tolypothrix spp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Tridontium tasmanicum Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Brian T. Coffey and Associares Limited, Hamilton. 5l '',1
Table 4 continued
T1 12 T3 f4 T5 T6A T68 T6C 17 T8A T88 T9 T10 T11 T12
unindent. leafy liverwort Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Vaucheria sp. Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy
Zygnema sp Left Bank macrophyte canopy at 12 m depth Right Bank macrophyte canopy at 12 m depth
Brian T. Coffey and Associates Limited, Hamilton. Table 5 Occurrence of free-floating* and shallow mound-forming plants (where s / m - sandy mud)
*Azolla rubra Left Bank macrophyte canopy Left Bank inshore of weed beds Right Bank macrophyte canopy Right Bank inshore of weed beds *Lemna minor Left Bank macrophyte canopy Left Bank inshore of weed beds Right Bank macrophyte canopy Bank inshore of weed beds
Crassula sinclairii Left Bank inshore of weed beds Bank inshore of weed beds
Eleocharis pusilla Left Bank inshore of weed beds Bank inshore of weed beds
Lilaeopsis ruthiana Left Bank inshore of weed beds Bank inshore of weed beds
Brian T. Coffey and Associates Limited, Hamilton. xlr
Table 5 continued
T1 T2 T5 T6A T6B T6C T7 T8A T88 T9 T10lT11 T12
Myriophyllum votschi¡ Left Bank inshore of weed beds Riqht Bank of weed beds Pratia angulata Left Bank inshore of weed beds Riqht Bank inshore of weed beds
Brian T. Coffey and Associares Limited, Hamilron. xllt
o/o Table 6 frequency of occurrence, mean (bold type) and standard deviation (in brackets) for a¡rimal taxa in relation to water depth and substrate type at Tl to Tl2 (where n = 5) Notes: (A) 0.16 cubic m sweep samples = from weed canopy: (B) = 6.9225 square m grab samples: (C) = on site counts / estimates (see methods) occurrence data only given for colonial animals (sponges - Ephydatia i nd bryozoans - Ètwiatetta¡
amphipods weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Bank Anisops wakefieldi weed canopy: Left Bank Right Bank 1 2 m depth: Left Bank Right Bank 25 m depth: Left Bank ioht Bank
Au st ro s i m u I i u m ti I lyard i an u m weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Bank
Brian T. Coffey and Associates Limited, Hamilton. Table 6 continued 7o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for anima-l taxa in relation to water depttr and substrate type at T1 to TL2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
Carassius auratus weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 60%, 1.0 (1.00) o 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 Bank 0 0 0 0 Chironomus spp. weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank BO%, 4-4 (2.70) 60%, 1.2 (1.30) 0 60%, 1.6 (1.52) BO%,2.8 (2.17) Rìght Bank 0 0 20%, 0.6 (1.34) 40%, 0.8 (1.30) 60%,2-4 (2.51) 25 m depth: Left Bank 4O%,1.8 (2.68) 40%,1.6 (2.16) 60%, 1.4 (1.34) 20%, 0.6 (1.34) 20%, 0.4 (0.89) Bank 0 0 60%, 3.4 (3.28 40%,1.6 (2.61 0 Ch lo rohyd ra vi ridi ssim a weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 m depth: 25 Left Bank 0 0 0 0 0 Rioht Bank 0 o 0 0 0
Brian T. Coffey and Associates Limited, Hamilton. Table 6 continued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in reiation to water depth a¡rd substrate t54pe at TI to TI2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
Culex pervigilans. weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 t Bank 0 0 0 0 0 Cura pinguis weed canopy: Left Bank 4o%, 1.0 (1.41) 0 0 2o%,0.2 (o.44) Right Bank 0 60%, 1.0 (1.00) 0 0 12 m depth: Left Bank 20%, o.2 (0.44) 0 0 0 0 Right Bank 0 0 0 4O%, 1.0 (1 .41) 0 25 m depth: Left Bank 20%,0.2 (0.44) 0 0 0 20%, 0.4 (0.8s) Bank 0 0 0 0 0 Ephydatia kakahuensis weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 4o%, - (-) 0 0 Right Bank 60%, - (-) 20%, - (-) 0 0 0 m depth: 25 Left Bank 0 0 0 0 0 Riqht Bank 0 0 0 0 0
Brian T. Coffey and Associates Limited, Hamilton. Table 6 contÍnued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for alima-l taxa in relation to water depth and substrate type at TI to TI2 (where n = 5)
Notes: (A) = 0.10 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
G I oss ip h on i a mu ltistriata weed canopy: Left Bank 0.8 (1.30) 0 0 40%, 0.8 (1.30) 20%, o-2 (o.44) Right Bank 0 0.8 0 0 2O%, O.4 (0.8s) 12 m depth: Left Bank 0 n 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 Bank 0 0 0 0 G obÌomo rph us cotidian us weed canopy: Left Bank 40%, 0.6 (0.89) 0 2O%,0.2 (0.44) 0 2O%,0.2 (O_44) Right Bank 0 0.8 2O%,0.2 (0.44) 2O%, O-2 (O.44) 40%, 0.8 (1.30) 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 o 0 0 0 0 0 n 0 0 0 0 Gyraulus corinna weed canopy: Left Bank 0 0 0 0 40%, 0.6 (0.8e) Right Bank 20%, 0.6 (1.34) 0 0 0 0 12 m depth: Left Bank 0 U 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 Bank 0 0 0 o 0
Brian T. Coffey and Associates Limited, Hamilton. XVII
Table 6 continued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in reiation to water depth and substrate type at TI to TI2 (where n = 5)
Notes: (A) = 0.10 cubic m sweep samples from weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimales (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
Homeodytes hookeri weed canopy: Left Bank 0 0 0 0 o Right Bank 0 0 0 0 0 .12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 o 25 m depth: Left Bank 0 0 0 0 0 Bank 0 0 0 0 0 Hygraula nitens weed canopy Left Bank 0 0 0 0 20%, 0.6 (1.34) Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 Bank n 0 0 0 0 Hyridella menziesi weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 40%, 0.4 (0.55) 0 2O%, O.2 (0.44) 0 0 Right Bank 20%,0.2 (0.44) 0 0 0 40%, 1.0 (1.41) 25 m depth: Left Bank 0 0 0 0 Bank 0 0 0 0
Brian T. Coffey and Associates Limited, Hamilton. XVIII
o/o TaL¡le 6 continued frequency of occutrence, mean (bold type) and standard deviation (in brackets) for anima_l taxa in relation to water depth and substrate type at TI to TL2 (where n = 5) Notes: (A) 0.10 cubic m sweep samples from weed = canopy: (B) = 6.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Ètuñatetta )
Lymnaea tomentosa weed canopy; Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Bank Microvelia macgregori weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Riqht Bank ostracods weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Riqht Bank
Brian T. Coffey and Associates Limited, Hamilton Table 6 continued %o frequency of occurrence, mearl (bold type) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at TI lo Tl2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 6.9225 square m grab samples: (C) = on site counts / estimates (see methods) occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Pluñatella\
Oxyethira albiceps weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Bank P arane ph rops pl anif rons weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank t Bank P aroxyeth i ra hen d e rsoni weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank t Bank
Brian T. Coffey and Associares Limited, Hamilton XX
Table 6 continued o/o frequency of occurrence, mean (bold t1,pe) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at TI to Tl2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods)
given - Occurrence data only for colonial animals (sponges Ephydatia and bryozoans - Plumatella )
Physa acuta weed canopy: Left Bank 60%, 1.0 (1.00) 10o, 4.4 (2.7O) 80%, 3.0 (3.53) 100%, 6.4 (3.58) 100%, 8.2 (4.82) Right Bank 80%, s.6 (4.s0) 60%, 2.8 (s.17) B0%, 3.8 (3.56) 60%, s.8 (5.72) 80%, 7-6 (7.57) 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 ht Bank 0 0 0 0 0 Planorbarius corneus weed canopy: Left Bank 60%, 0.8 (0.84) 40%, 2.6 (3.58) 60%, 1.4 (1.52) 80%,2.6 (2.70) 60%, 1.0 (1.22) Right Bank 60%, 2.0 (1.87) 40%,2.0 (3.e4) 2O%, O.2 (0.45) 40%, 0.6 (0.8s) 2O%, O.2 (O.44) 1 2 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 depth: 25 m Left Bank 0 0 0 0 0 Bank 0 0 0 0 0 Plumatella repens weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank - 2o%, o 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 Riqht Bank 0 0 0 0
Brian T. Coffey and Associates Limited, Hamilton. XXI
Table 6 continued o/o frequency of occurrence, mean (botd type) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at Tl to TI2 (where n = 5) (A) 0.16 cubic m Notes: = sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods) occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - pluñatella)
Potamopyrgus antipodaru m weed canopy: Left Bank 60%, 6.0 (7.04) 60%, 3.0 (5.61) 60%, 6.8 (6.e8) 100%, 8.2 (7.33) BO"/", 76 (159.05) Right Bank 40%, 0.6 (0.89) 80%, s.2 (7.33) 60o/", 29.2 (51.66) 2O%,0.2 (O.44) 4Oo/", 1.2 (1.64) 1 2 m depth: Left Bank Bo%, 6.4 (s.13) 0 0 0 40%, 0.8 (1.30) Right Bank 0 60%, 1.6 (1.s2) 60%, s.4 (3.e7) 0 20%,1.4 (3.13) 25 m depth: Left Bank 0 0 0 0 0 Bank 0 0 20%.1.4 (3.13 0 0 Procorduria grayi weed canopy: Left Bank 20"/",1.4 (3.13) 0 0 0 40%,0.4 (0.s5) Right Bank 0 0 0 20%,0.6 (1.34) 20%,0.6 (1.34) 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 0 0 0 Bank 0 0 0 0 Retropinna retropinna weed canopy: Left Bank 20%,0.6 (1.34) 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 U 0 0 25 m depth: Left Bank 0 0 0 0 0 t Bank 0 0 0 0 0
Brian T. Coffey and Associares Limited, Hamilton. XXII
Table 6 continued %o frequency of occurrence, mean (bold type) a¡rd standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at TI to -1L2 (where n : 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 6.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plurñatella)
Rhantus pulverosus weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Bank
Sca rd i n i us e ryth ropthal amus weed canopy: Left Bank Right Bank 12 m depth: Left Bank Right Bank 25 m depth: Left Bank Riqht Bank S phae ri u m novaezelandi ae weed canopy: Left Bank Right Bank 12 m depth: Left Bank Fìight Bank 25 m depth: Left Bank t Bank
Brian T. Coffey and Associates Limited, Hamilton. XXIII
Table 6 continued %o frequency of occurrence, mean (bold type) ald standard deviation (in brackets) for taxa in relation to water animal depth and subsiiate type at rl to T12 (where n = 5) Notes: (A) = 0' 16 cubic m sweep samples from weed canopy: (B) o.o22s = square m grab samples: (c) = on site counts / estimates (see methods)
weed canopy: Left Bank 0 0 o Right Bank 0 0 0 0 12 m depth: Left Bank B0%, 6.2 (4.5s) 0 60%, 2.8 (2.s5) 0 80%,2.4 (2.3O) Rlght Bank 20%, 0.4 (0.8e) 40"/" 1.2 (1 .64) 0 60%, 1.6 (1.82) 8O%, 8-2 (8.47) 25 m depth: Left Bank 60%, s.4 (8.88) BO"/" s.2 (8.44) 60y", 12.4 (23.34) 100%, 8.8 (6.02) 60%, Riqht Bank 6.0 (6.74) 60% 2.8 (2.ss) 0 0 BO%. (13.30) 13.4 60%. 3.0 t3.671 0 weed canopy: Left Bank BO%,12.2 (8.82) 60%, 6.0 (6.60) 80%, s.6 (13.3s) Right 60%, e.6 (11.52) 60%, 7.0 (8.00) Bank 80%, 7.8 (5.36) 80%, s.8 (8.87) 60%, 8.2 (7.es) 12 m 60%, 3.2 (5.s4) 80%, 2.8 (2.05) depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 Riqht Bank 0 0 0 0 0 ...... _q.. 0
Brian T. Coffey and Associates Limited, Hamilton. XXIV
Table 6 continued 7o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at Tl to TI2 (where n = 5) Notes: (A) 0.10 cubic m sweep samples from = weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given lorcolonial animals (sponges - Ephydatia andbryozoans - Ètu¡ñatela)
amphipods weed canopy: Left Bank 2O"/", 1.8 (4.O2) 1Oo%, 6.0 (4.24) 20%, 0.8 (1.78) 40%, 0.8 (1.30) 1OO"/", 212 (353.4) 100% - 278 (332.81) Right Bank 4O%,1.0 (1.73) 40"k, 13.6 (20.18) 80%, 3.6 (3.05) BO"/", 29 (20.46) 100%, 16.8 (13.59) 100% - 306 (263.96) 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Fìioht Bank 0 Anisops wakefieldi weed canopy: Left Bank 0 0 0 0 4OV", 1.2 (1.64) 0 Right Bank 0 0 40%, 0.6 (0.8s) 0 0 0 12 m depth: Lett Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0 Austros imu I i u m ti llya rd ianu m weed canopy: Left Bank 0 0 0 0 0 a,v,o,- Right Bank 0 0 0 0 o 0 12 m depth; Left Bank 0 0 0 0 0 Right Bank U 0 0 0 25 m depth: Left Bank 0 0 Riqht Bank 0
Brian T. Coffey and Associates Limìted, Hamilton XXV
Table 6 continued o/o fr-equency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in relation to water deptÍr ald substrate type at T1 to TI2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only gìven for colonial animals (sponges - Ephydatia and bryozoans - Plumatellal
Carassius auratus weed canopy: Left Bank 0 0 0 0 100%, 8.8 (6.02) 0 Fìight Bank 0 0 0 0 0 12 m depth: Left Bank 0 0 : 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0 Chironomus spp- weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 40%,2.0 (3.08) 0 80%,2.6 (2.41) 0 80%, 8.0 (8.80) Right Bank 0 Bo%, 5.8 (3.35) 60%, 4.0 (3.67) 8O"/",9.4 (10.38) 100%, 10.8 (7.56) 25 m depth: Left Bank 4O"/", 1.0 (1.41) Riqht Bank 4O"/", 1.2 (1 .64) C hloro hydra vi rid i ss i ma weed canopy: Left Bank 0 0 0 0 0 100%, - Flight Bank 0 o 0 0 0 0 0 12 m Left Bank 0 n depth: 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riohl Bank 0
Bdan T. Coffey and Associates Limited, Hamilton. XXVI
(in Table 6 continued %o frequency of occurrence, mean (bold type) and standard deviation brackets) for animal taxa iã relation to water depth and substrate type at Tl to TL2 (where n = 5) m grab samples: (C) on site counts / estimates (see methods) Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 6.9225 square =
Occurrence dala only given lor'colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
Culex pervigilans weed canopy: Left Bank 0 v,a,-,- 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0 Cura pinguis weed canopy: Left Bank 0 0 10o%,2.4 (2.3) 2O%, 0.2 (O.44) 0 60%, 1.6 (1.82 Right Bank 4O%, 1.6 (2.16) 0 800%, 2.8 (2.68) 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 2o%, 0.4 (0.89) 20%, 0.2 (0.44) 0 0 25 m depth: Left Bank 0 Fliqht Bank 0 Ephydatia kakahuensis weed canopy: Left Bank n 0 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 4o%,- o 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0
Brian T. Cofley and Associates Limited, Hamilton XXVII
for animal of occurTence, mean (bold t1,pe) and standard deviation (in brackets) Table 6 continued %o frequency (where taxa in relation 1o water depth ald subsliate type at Tl to TI2 n = 5) counts / estimates (see methods) from weed canopy: (B) 0.0225 square m grab samples: (c) = on site Notes: (A) = 0.16 cubic m sweep samples = ' ffi;;;;; äätr oïly giurn fóitoionial animals (sionge s - Eþhydatia and bryozoans Plumatella)
Glossiphonia multistriata 0 0 0 0 weed canoPY: Left Bank 0 0 0 0 0 Righl Bank 0 n 0 0 0 0 12 m dePth: Left Bank 0 0 n 0 0 0 Right Bank 0 25 m dePth: Left Bank 0 Right Bank 0
Gob i omo rphus cotidi anus (0.55) 60%, 0.8 (0.84) 60%, 0.8 (0.84) 40%, 0.6 (0.8e) weed canopY: Left Bank 2o%, 0.4 (0.8s) 40%, 0.4 (0.55) 40%, 0.4 0.6 (0.89) 60%, 1.4 (1.34) 2O%, 0.2 (O.44) Right Bank 60%, 1.4 (1.34) 60%, 0.8 (0.84) 4O%,1.0 (1-41) 4o%, 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0 Gyraulus corinna 0 0 0 weed canoPY: Left Bank 0 0 o n 0 0 0 0 Right Bank n : 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0
Brian T. Coffey and Associates Limited, Harnilton- XXVIII
Table G continued o/o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for a¡rimal taxa in relation to water depth and substrate type at TI to TI2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence dala only given for'colonial animals (sponges - Ephydatia and bryozoans - Plumatella)
Homeodytes hookeri weed canopy: Left Bank 0 0 0 0 2O"k, 1.4 (3.13) o Right Bank 0 0 0 0 0 o 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Fìiqht Bank 0 Hygraula nitens weed canopy: Left Bank 0 0 0 0 0 0 Right Bank 0 0 0 0 0 o 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0 Hyridella menziesi weed canopy: Left Bank 0 0 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 0 0 40%, 0.6 (0.8s) 0 0 Fight Bank 0 0 0 0 0 25 m depth: Left Bank 0 R¡aht Bank 0
Brian T Coffey and Associates Limited, Harniiton. XXIX
deviation (in brackets) for animal Table 6 continued %o frequency of occurrence, mean (bold type) ald standard taxa in relation to water depth and subsliate type at TI to TI2 (where n = 5) canopy: (B) 0.0225 square m grab samples: (C) = on site counts / estimates (see methods) Notes: (A) = 0.16 cubic m sweep samples from weed =
- öä;".; äåtr given foilolonial anìmals (s¡ionges - Ephydatia and bryozoans Plumatellal "nfy
Lymnaea tomentosa 0 0 0 weed canopY: Left Bank 20%, 0.4 (0.8s) 0 0 0 0 Fìighl Bank 0 0 0 0 0 0 o 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 25 m dePth: Left Bank 0 Riqht Bank 0 Microvelia macgregor¡ a ooccc a,v,c,c,c c,-,4,v,- oo weed canoPY: Left Bank ,c,o,c -,-,-,c,c cc Right Bank ,c,c,c ccaac cc -,c,c,c,v 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 U 0 0 25 m depth: Left Bank 0 Riqht Bank 0 ostracods 0 weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 0 o 12 m depth: Left Bank v,v,v,a,v 0 v,o,-,4,v ,a,a,v Right Bank 0 v, a, a, v, v,a,v,o,- v,o,a,-,o ,-,4,4 25 m depth: Left Bank v,a,a,v,v Riqht Bank C,V,V,A,V
Brian T. Coffey and Associates Limited, Hamilton. XXX
standard deviation (in brackets) f-or animai %o frequency of occurrence, mean (bold type) and Table 6 continued (where n 5) taxa in relâtion to water depth and substiate type at TI to T12 = estimates (see methods) weed canopy: (B) 0.0225 square m grab samples: (c) = on site counts / Notes: (A) = 0.16 cubic m sweep samples from =
- bryozoans 'Plunatetta\ ôä;äõ är ..ly si;.n f;;ä.ü'd ãt*áis lsponses tþnydatia and
Oxyethira albicePs 0 0 0 0 weed canoPY: Left Bank 0 0 0 0 Right Bank 0 0 0 0 0 0 '1 2 m dePth: Left Bank o 0 0 0 0 Right Bank 0 0 25 m dePth: Left Bank 0 Riqht Bank 0
P araneph rops Pl an if ro ns 0 0 0 0 weed canoPY: Left Bank 0 0 0 0 0 Right Bank U 0 0 0 0 0 12 m depth: Left Bank 0 20'k o.2 (0.44) 0 0 0 Fìight Bank 0 0 25 m depth: Left Bank 0 Riqht Bank 0
P aroxyeth i ra hende rsont 0 0 0 weed canoPY: Left Bank 0 0 0 0 0 Right Bank 0 c,v,-,- 0 0 .l 0 0 0 2 m dePth: Left Bank 0 0 0 0 Right Bank 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0
Brian T. Coffey and Associates Limited, Hamilton. XXXI
Table 6 conlinued Zo frequency of occurrence, mean (botd type) and standard deviation (in brackets) for anirnal taxa in relation to water depth and substrate type at T1 to TI2 (where n = 5) grab samples: (C) on site counts / estimates (see methods) Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.0225 square m =
Occurrence data only given for'colonial animals (sponges - Ephydatia and bryozoans - Plumatellal
Physa acuta weed canopy: Left Bank 60%, 7.0 (7.35) 80%, 37.8 (49.68) 6o%, 3.4 (3.58) 100%, 183 (247.s) 100%, 3s4 (310.3) 100%, 162 (328.6) Right Bank 60%, 1.0 (1.22) 100%, 31 (38.82) 4O%, 7.O (10.34) 100%, 43 (41.17) 1O0%, 137 (281.2) 1oo%, 392 (350.9) 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Rioht Bank 0 Planorbarius corneus weed canopy: Left Bank 40%, 1.4 (2.61) 8o%, 2.8 (3.56) 2o%, 0.4 (0.8e) 60%, 2.0 (3.63) 0 0 Right Bank 60%, 0.6 (0.55) 20%,0.2 (0.44) 8o%, 1.0 (1.22) 20%, O.2 (0.44) 2O%, O.2 (0.44) 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank ô Plumatella repens weed canopy: Left Bank 0 0 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 0 Right Bank 0 n 0 0 0 25 m depth: Left Bank 0 Riqht Bank o
Brian T. Coffey and Associates Limited, Hamilton. XXXII
Table 6 continued o/o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for a¡rimal taxa in relation to water depth and substrate type at Tl to TI2 (where n = 5) (A) Notes: = 0.10 cubic m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence dala only given for colonial (sponges - - animals Ephydatia and bryozoans Ptu¡ñatetta )
Potamopyrgus a ntipoda ru m weed canopy: Left Bank 40%, (1.30) 0.8 60%, 1.4 (1.52) 0 0 0 0 Right Bank 80%, 7.0 (6.20) 2o%,2.4 (5.37) 0 0 0 40 1.0 (1 .41 12 m depth: Left Bank 0 ) 0 0 0 0 Right Bank 0 40%,1.6 (2.61) 0 0 0 25 m depth: Left Bank ô Riqht Bank 0 Procorduria grayi weed canopy: Left Bank 0 0 0 0 0 0 Right Bank 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 n 0 Right Bank 0 0 0 0 0 25 m depth: Left Bank 0 Rioht Bank 0 Betropinna retropinna weed canopy: Left Bank 0 0 0 0 0 0 Fìight Bank 40%, 0.6 (0.89) 0 0 0 0 12 m depth: Left Bank U 0 0 0 0 Fìight Bank 0 0 0 0 0 25 m depth: Left Bank 0 Fìioht Bank 0
Brian T. Coffey and Associates Limited, Hamilton. XXXIII
(in brackets) for animal Tabte 6 continued vo frequency of occurrence, mean (bold type) and standard deviation taxa in relation to water depth and subsiiate type at T1 to T12 (where n = 5) square m grabsamples: (c) counts/estimates (see methods) Notes: (A) =0.16 cubic m sweepsamples fromweed canopy: (B) = 0.0225 =onsite
- ôäi¡g.õ äãra onfy given for ôolonial animals (s¡ìonges - Ephydalia and bryozoans Plunalellal
Rhantus pulverosus 0 20%, 0.4 (0.8e) 0 weed canopy: Left Bank 0 0 0 0 0 Fight Bank 0 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 25 m dePth: Left Bank 0 Riqht Bank 0
S c a rdin i u s e ryth roPlhalamus 0 2o%, 0.6 (1.34) weed canopy: Left Bank 0 0 0 0 0 Right Bank 0 n 0 0 0 0 0 0 12 m depth: Left Bank 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 Riqht Bank 0
S ph ae ri u m n ovaezelandi ae 0 weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 0 0 0 60%, 2.6 (3.13) 12 m depth: Left Bank 0 0 0 (8.82) (0.8e) Right Bank 0 20%, 0.4 (0.8s) 60%, 0.8 (0.84) 80"/",7.4 2o%, 0.4 25 m depth: Left Bank 4o%, 0.4 (0.54) Riqht Bank 0
Brian T. Coffey and Associates Limited, Hamilton. XXXIV
Table 6 continued o/o frequency of occurrence, mean (bold t¡¿pe) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate t54pe at TI to T12 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 6.9225 square m grab samples: (C) = on s¡te counts / estimates (see methods)
Occurrence data only given for colonlal animals (sponges - Ephydatia and bryozoans - Plumatella)
tubif icids weed canopy: Left Bank 0 0 0 0 0 0 Right Bank 0 0 0 0 0 12 m depth: Left Bank 80%, 6.6 (3.8s) 0 : 100%, 1s (10.04) 0 1OO"/", 47O (210.9) Right Bank 0 80%, 17_6 (1 2. s8) r00%, 12.2 (6.65) 100%, 266 (272.1) 100%, 500 (234.s) 25 m depth: Left Bank 100%, 11.2 (6.18) 6O"k, 21.8 (30.96 Xanthocnemis zelandica weed canopy: Left Bank BO"/", 11.2 (3.83) 80%, 7.4 (6.06) 60%, 1.8 (2.4e) 100%, 6.2 (5.36) 60%, 4.2 (5.36) 60%, 0.8 (0.84) Right Bank 60%, 9.4 (s.1s) 100%, 6.8 (3.90) 60%, 6.2 (6.06) 60%, 1.0 (1.00) 0.4 (0.55) 40%, 0.8 (1.30) 12 m depth: Left Bank 0 0 0 0 0 n Right Bank 0 0 0 0 25 m depth: Left Bank 0 Rioht Bank 0
Brian T. Coffey and Associates Limited, Hamilton XXXV
Table 6 continued %o frequency of occurrence, mean (bold type) and sta¡rdard deviation (in brackets) for animal taxa in relation to water depttr and subst¡ate type at TI to'll2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumalella)
T9 T10 111 T12
Brian T. Coffey and Associates Limited, Hamilton. XXXVi
Table 6 continued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for ani¡¡al taxa in relation to water depth and substrate type at Tl to T12 (where n = 5) (A) Notes: = 0.16 cubic m sweep samples from weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods) occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Ètwñatetta¡
T9 T10 T11 112
Bria¡ T. Coffey and Associates Limited, Hamilton. xxxvlt
Table 6 continued o/o frequency of occurrence, mean (bold type) and standa¡d deviation (in brackets) for animal taxa in relation to water depth and substrate type at TI to TI2 (where n = 5) grab samples: (C) on site counts / estimates (see methods) Notes: (A) = 0.16 cubic m sweep samples from weed canopyt (B) = 0.0225 square m =
- Occurrence data only given for-colonial animals (sponges 'Ephydatia and bryozoans Plumateila'l
Culex pervigilans. weed canoPY: Left Bank 0 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 Rioht Bank 0 0 o 0 Cura pinguis weed canopy: Left Bank 0 0 0 4o%, 1.0 (1.73) Right Bank 0 4o%, 0.8 (1.30) 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 Riqht Bank 0 0 o 0 Ephydatia kakahuensis weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 4o%, - (-) 25 m depth: Left Bank 0 0 0 0 Riqht Bank 0 0 0 0
Brian T. Coffey a¡rd Associates Limited, Hamilton. XXXVITI
Table 6 continued o/o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate ty¡re at Tl to TL2 (where n = 5) (see Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates methods)
Occurrence data only given lorbolonial animals (sponges - Ephydatia and bryozoans - Plumalellal T9 T10 T11 T12
Brian T. Coffey and Associates Limited, Hamilton. KXXTX
Table 6 continued o/o frequency of occurrence, mean (bold type) a¡rd standard deviation (in brackets) for animal taxa in relation to water deptÌr and substrate type at Tl to Tl2 (wtrere n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plunatella)
T9 T10 T11 T12
Brian T. Coffey and Associates Limited, Hamilton. KI
Table 6 continued o/o frequency of occurrence, mean (bold type) and sta¡rda¡d deviation (in brackets) for animal taxa in relation to water depth and substrate t54pe at Tl to TL2 (where n = 5)
Notes: (A) = 0.10 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only gìven for colonial animals (sponges - Ephydatia and bryozoans - Plunatella)
T9 T10 T11 T12
Brian T. Coffey and Associates Limited, Hamilton. xli
Table 6 continued 7o frequency of occurrence, mean (bold type) and standa¡d deviation (in brackets) for arrimal taxa in relation to water depth and substrate type at Tl to T12 (where n = 5) Notes: (A) = 0.10 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Pluñatella\
T9 Tl0 T11 T12
Brian T. Coffey and Associates Limited, Hamilton. xlii
Table 6 contjnued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for animal taxa in relation to water depth a¡rd subst¡ate t¡,pe at Tl to Tl.2 (where n = 5) Notes: (A) = 0.10 cubic m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods) occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - pluñatella)
T9 T10 Tlf T12
Brian T. Coffey and Associates Limited, Hamilton. xIiü
Table 6 continued %o frequency of occurrence, mean (botd type) and standard deviation (in brackets) for animal taxa in relation to water depth and substrate type at Tl to TI2 (where n = 5) (A) 0.16 cubic Notes: = m sweep samples from weed canopy: (B) = 0.022S square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Ptuúatella)
T9 T10 Tll T12
Brian T. Coffey and Associates Limited, Hamilton. xliv
Table 6 continued %o frequency of occurrence, mean (bold type) and standard deviation (in brackets) for arrimal taxa in relation to water depth and substrate ty¡re at TI to Tl2 (where n = 5) Notes: (A) 0.16 cubic m sweep samples from = weed canopy: (B) = 0.0225 square m grab samples: (C) = on site counts / estimates (see methods)
Occunence data only given for culonial animals (sponges - tþnyAatia and bryozoans - etuñatetta¡
T9 T10 T11 T12
Brian T. Coffey and Associates Limited, Hamilton. xliv
Table 6 continued %o frequency of occurrence, mean (bold type) and standa¡d deviation (in brackets) for animal taxa in relation to water depth and substrate type at Tl to Tl2 (where n = 5) Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = Q.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Pluñateltal
T9 T10 T11 T12
Rhantus pulverosus weed canopy: Left Bank o 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 0 0 0 S c ard i n i u s e ryth ro pth a I am u s weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 0 0 0 Sphaeriu m novaezelandiae weed canopy: Left Bank 0 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 0 20%, 0.4 (0.8s) 40%, 0.6 (0.8e) 0 Right Bank 40%,1.6 (2.61) 2O%, 0.2 (0.44) 0 0 25 m depth: Left Bank 2O%, 0.6 (1.34) 0 60%, 4.0 (3.74) 0 0 40%.2.6 (3.58 0 0
Brian T. Coffey and Associates Limited, Hamilton. xlv
Table 6 continued 7o frequency of occurrence, meal (botd type) and standard deviation (in brackets) for anirnal taxa in relation to water depth and substrate type at Tl to TL2 (where n = 5)
Notes: (A) = 0.16 cubic m sweep samples from weed canopy: (B) = 9.9225 square m grab samples: (C) = on site counts / estimates (see methods)
Occurrence data only given for colonial animals (sponges - Ephydatia and bryozoans - Plumalella)
tubif icids weed canopy: Left Bank 0 0 0 Right Bank 0 0 0 0 12 m depth: Left Bank 100%, 1s (1s.61) 60%, 6.6 (7.8e) 80"/", 73 (105.2) 0 Fìight Bank 80%, s (7.2s) B0%, 12.2 (8.82) 0 0 25 m depth: Left Bank 100%, s.8 (6.46) B0%, 11.0 (13.71) 8O"/", 13.2 (13.66) 0 Rioht Bank 60%. 4.0 (s.40) 80%. 117 (226.1\ 0 0 Xanthocnemis zelandica weed canopy: Lett Bank 8O%, 11.2 (9.09) 60%,7.2 (7.33) 10o"/", 7.2 (5.54) 1OO"/., 14 (10.50) Right Bank B0%, e.4 (5.81) 80%, e.0 (s.64) 8o%, 8.6 (6.43) 80%, 2.8 (2.e5) 12 m depth: Left Bank 0 0 0 0 Right Bank 0 0 0 0 25 m depth: Left Bank 0 0 0 0 0 0
Brian T. Coffey and Associates Limited, Hamilton. xlvi
Table 7 Deep v¡ater benthos counts, January 1996
Locality Depth replicate substrate Chironomus wotms Cura zelandicus d/mud 17 70 2
2 d/mud 14 50 1 Site A 45 3 d/mud 30 0 4 d/mud 15 29 0 5 d/mud 19 43 3 f req. 100% 10O Y" 60% SD 2.7019 16.832 1.3038 mean 15.4 44.4 1.2
d/mud 23 40 1 2 d/mud 12 43 0 Transect 35 3 d/mud 19 61 3
5 4 d/mud 11 48 1 5 d/mud 1't 53 0 f req. 100% 100 % 60% SD 5.4955 8.3367 1.2247
mean 15.2 49 1 1 d/mud 12 4 0 2 d/mud 20 7 0 Transect 35 J d/mud/o 7 5 0 6A 4 d/mud/o I I 0 '19 d/mud 13 0 0/" f req. 100 "/" 100 0% SD 5.8566 3.5777 mean 13.4 7.6 d/mud 21 20 0 2 d/mud 27 14 0 Transect 45 3 d/mud 16 16 0 6A 4 d/mud 20 30 0
5 d/mud 19 12 1 0/" f req. 100 100% 20% SD 4.0373 7.1274 0.4474 mean 20.6 18.4 0.2 1 d/mud/o 0 0 0 2 d/mud/o 0 3 0 Transect 35 3 d/mud/p 1 0 0 I 4 d/mud/o ö 1 0 5 d/mud/o 0 2 ô f req. 40% 60% 0% SD 1.3038 1.3038 mean 08 1.2 1 d/mud I 5 0 2 d/mud 11 7 0 Transect 45 3 d/mud 14 4 0 I 4 d/mud 13 9 0 5 d/mud 7 11 0 o/" f req. 100 100 % 0 "/. SD 2.8636 2.8636 mean 10.8 7.2
Brian T. Coffey and Associates Limited, Hamilton. xlvii
Table 7 continued
Locality Depth replicate substrate Chironomus worms Cura zelandicus 1 d/mud I I 0 2 d/mud 10 7 Transect 0 55 3 d/mud 16 1'l 0 9 4 d/mud 12 13 0 5 d/mud þ 3 0 f req. 100 "/. 100 0/" 0% SD 3.8478 3.8471 mean 10.4 84 1 d /mud lo 7 30 0 2 dlmud/o 7 2 0 Transect 35 3 d/mud/o 5 0 12 0 4 d/mud/o 3 1 0 5 d/mud/p Þ 4 0 o/" freq. 100 80% 0% SD 1.6733 12.72 mean 5.6 74 1 dlmudln o 0 0 2 d/mud/o 6 15 0 Transect 45 LI d/mudlo 4 0 12 4 d/mudlo 0 I 3 0 5 d/mud/o 2 0 0 o/" lreq. 100 40% 0% SD 2.8636 6.5038 mean 5.8 3.6 1 d/mud 4 5 0 2 d/mud 10 0 0 Transect 55 3 d/mud '10 1 0 12 4 d/mud 9 0 0 5 d/mud 3 0 0 f req. 100% 40% o o/" SD 3.4205 2.1679 mean 72 12
Brian T, Coffey and Associates Limited, Hamilton.