Journal of Aquatic Ecosystem Stress and Recovery 9: 249–258, 2002.© 2002 Kluwer Academic Publishers. Printed in the Netherlands.

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The distribution of Austrocrangonyx new species (Crustacea: Amphipoda)on the eastern New England plateau, Australia, with reference to riparianclearing

Katie Brown1,2 & Brian V. Timms1,∗1School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, 23082Present address: King Island Natural Resource Management Group, P.O. Box 293, Currie, King Is, Tas., 7256(∗Author for correspondence: E-mail: brian.timms@newcastle.edu.au)

Received 12 March 2002; accepted in revised form 7 February 2003

Key words: amphipods, coarse particulate organic matter, New England Australia, riparian clearing, temperature

Abstract

The amphipod Austrocrangonyx n.sp. lives in forested streams above 1165m on the eastern New England plateauin NSW. Classification and Regression Tree (CART) analysis and principal component biplots showed low streamtemperatures and high levels of coarse particulate organic matter (CPOM), among many environmental factorsmeasured, were the main factors associated with its distribution and abundance. Riparian clearing, which increaseswater temperature and greatly reduces CPOM, is associated with local extinction of Austrocrangonyx. Secondaryreafforestation is not accompanied by return of the amphipod.

1. Introduction

Clearing of riparian vegetation affects stream macroin-vertebrates via disturbance of flow regimes, reducedorganic matter input, and increased water tempera-tures, sedimentation, and primary production (Stone& Wallace, 1998). Amphipods could be expected tobe affected by such changes since they belong tothe shedder functional feeding group, and many livein cold water forested environments (Allan, 1995;Wallace & Webster, 1996).

In Australia there have been few studies on theeffect of forest clearing on stream invertebrates, andon amphipods in particular. In Victoria, Reed et al.(1994) found that shedder abundances were signifi-cantly higher and grazer abundances lower at forestedsites than at pasture sites, but in Tasmania Swain etal. (1993) observed comparable densities of shreddersbetween forest and pasture sites. The later authorshowever noted decreases in shedder abundances inlitter bags where sedimentation from forestry prac-tices filled interstitial spaces. In Western Australia,

Growns & Davis (1991) recorded that the amphipodPerthia cf acutitelson dominated in forested reaches ofstreams, but was visibly absent from streams affectedby clearing. They could not specify the exact cause ofsuch a distribution, but attributed it to either changesin the CPOM:FPOM ratio or increased salinity.

In the higher parts of the New England plateauof northeastern NSW, there are representatives ofat least three genera of amphipods, Austrocran-gonyx, Neoniphragus and Psuedomoera (Adlem &Timms, 2000). All are cold water stenotherms andlive in forested streams. In a southern extension ofthe area, at Barrington Tops, Austrocrangonyx spp.dominate in forested streams but are absent in nearbystreams cleared for pasture (Adlem & Timms, 2000).An undescribed species of Austrocrangonyx lives instreams of the eastern escarpment of the New Englandregion around Ebor. It is the aim of this work to map itsdistribution, to identify major environmental factorsaffecting its ecology and to examine the impact ofriparian clearing on its distribution.

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Figure 1. Site map indicating the presence and absence of Austrocrangonyx n.sp. on the eastern New England Plateau near Ebor, ∼420 kmNNE of Sydney.

2. Study site and methods

The area of study was from Ebor to Dorrigo on theeastern rim of the New England plateau in north-eastern New South Wales, about 420 km north-northeast of Sydney (Figure 1). Altitudes range fromca 1000 m to 1563 m and mean annual precipitation is>2000 mm (State Forests, 1995). Natural vegetationcommunities range from dry eucalypt woodlands torainforests (Mather, 1991). Stream waters are essen-tially clear (<10 NTU), of very low conductivity(<0.1 mS/cm), and neutral to slightly alkaline in pH.Temperatures ranged from 1–22 ◦C (Mather, 1991;Boulton et al., 1995). Most of the valleys and manyridges were cleared in the 1830s and are a mixture ofnative grasses and introduced herbs, utilized for cattlegrazing (Fahey, 1976).

Sampling of the study area was conducted betweenDecember 1998 and February 1999. Collection siteswere established within each stream of the studyregion, to encompass a range of altitudes >1000 m(a.s.l) and vegetation communities. Each site was

sampled using the kick sampling method (Marchant,1989; Chessman, 1995), with four by 1 minutesamples taken, and a mean number caught per minutecalculated. A more detailed study was also conductedon the Guy Fawkes River, to identify in-stream vari-ability, and involved eight quarter minute samples,with means and standard deviations calculated.

Environmental factors recorded at each samplingsite included altitude, stream width, depth, substratesize assessed visually using the Wentworth scale(Allan, 1995), and general stream morphology rankedas 1 = riffle, 2 = pool, 3 = spring, and 4 = waterfall.(Most of the collection sites established were riffles,given the commonality of amphipods in this habitat(Adlem & Timms, 2000).

Vegetation community type, percentage foliagecover (measure of shading and potential leaf drop),and the amount of CPOM caught in sampling, werealso recorded. In particular the CPOM from each sitewas dried and burnt in a muffle furnace to determinethe carbon percentage (Allan, 1995).

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Finally, general water chemistry was assessed ateach site by a Horiba U-10 Water Quality Checker,to determine temperature, pH, conductivity, turbidity,and dissolved oxygen. Temperature data loggers,recording hourly during February 1999 from onestation at Deer Park Creek, and two at Guy FawkesRiver, further supported this analysis.

To compliment this research, two experimentswere performed to test amphipod colonizationand survivorship under different stream conditions,between March and April 1999. Firstly, mesh poucheswere filled with 50 g of rainforest leaf litter toassess preferential colonization of CPOM at fourstations within the Guy Fawkes River. The poucheswere secured in triplicate to the stream bed for 30days, at the rainforest, wet eucalypt, tea-tree scruband pasture dominated sections. Secondly, to assessthe importance of food and shelter availability onthe survival of Austrocrangonyx n.sp. along a rivercontinuum, three containers (12 × 20 × 8 cm withpanels removed and replaced with 1 mm flywire)containing rainforest leaf litter, small cobbles and50 amphipods each, were placed at the same fourstations in Guy Fawkes River. After two weeks thenumber of amphipods alive and dead were recordedfor each container. During both experiments therewere no abnormally high daily temperatures (Bureauof Meteorology, weather data).Two major statisticaltechniques were employed to assess and compare thefactors predicting amphipod presence and abundancein both the regional and local studies. Classificationand Regression Tree (CART) analysis was selectedas a predictive model that automatically handled issuesof non-normal distribution, heterogeneous varianceand mixed measurement scales in the data (Verbyla,1990; Ripley & Venables, 1994; Bell, 1996). Theanalysis works by assessing variances between, andwithin, the environmental variables with regardsto the presence of the fauna. These variances arebroken down into progressive diagrammatic trees,which are branched by the level of influence eachenvironmental factor has over the presence of thespecies. This continues until less than 10 sample sitesare constrained by a given environmental condition,or variable. For this study the multiple predictivevariables were the environmental factors and thedependent variable was the amphipods counts. Fromthe statistical package S-PLUS, the CART programcreates diagrammatic trees which predict presence(classification trees) or abundance (regression trees)of amphipod populations and moreover gives the

environmental factor contributing most to the diver-gence (For details see Breiman et al., 1984, Verbyla,1990, and Bell, 1996).

Principal Components Analysis (PCA) wasapplied to identify relationships between environ-mental variables from both the regional and localstudies. The resultant biplots of relationships betweenenvironmental variables are superimposed withthe sampling sites and amphipod abundances.Interpretation follows Gabriel (1971).

3. Results

3.1. Amphipod distribution

Amphipods, all identified as Austrocrangonyx n.sp.,were found at 23 out of 53 sites investigated. Positivesites lay above 1165 m and usually were in rain-forests, but some had tea-tree scrub or wet eucalyptforest in the riparian zone (Figure 1). Streams ineucalypt woodlands and in pastures, with two excep-tions, lacked amphipods regardless of the altitude(Figure 1). The exceptions were two pasture stationsa few hundred metres downstream of forests; both hadhigher amounts of CPOM than usual and both had justa few amphipods.

Most positive stations lay on Guy Fawkes River,upper Majors Creek, Alans Water and Middle Creek;these streams drain adjoining catchments on basalteast of Ebor (Figure 1). Other streams in forestedbasalt to the south of, and to the far east of Eborcontained amphipods sporadically (e.g. Five Day Ck.,Deer Park Ck.), or seemed to lack them (e.g. Styx R.,Bangalow Ck.). Amphipods were also absent fromstreams draining the granites of the Cathedral RocksNational Park despite high altitudes and forest cover(Figure 1).

3.2. Environmental parameters

Most of the environmental variables measured rangedwidely (Appendix 1); mean values (± SD if appro-priate) were width 3.4 ± 1.6 m, depth 0.22 ± 0.20 m,CPOM 143 ± 86 g/minute, turbidity 5.7 ± 6.2 NTU,conductivity 20 ± 4.8 µS/cm, pH 6.7 ± 0.9, andoxygen concentration 7.7 ± 0.8 mg/L. At each stationthe substrate was of large pebbles in riffles.

Stream temperatures at time of sampling rangedfrom 12.4 ◦C to 23.6 ◦C in summer. These wereinfluenced to some extent by daily variation, so

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the temperatures recorded by the data loggers weremore exacting (Table 1). These showed lower meantemperature, maximum temperature and diurnal rangein the rainforest station compared to values at themuch lower altitude tea-tree station or at lower altitudepasture station.

Values for coarse particulate organic matter(CPOM) and percent carbon varied widely betweensites. The amount of CPOM was not related tothe type of riparian vegetation though amphipodsusually occurred in sites with larger amounts (Table 2).However in two way ANOVA tests these differenceswere not significant (CPOM: vegetation type F = 0.08,F crit = 7.7; CPOM: amphipods F = 1.4, F crit 6.4).Furthermore there was no relationship between CPOMand % carbon content within sites (r = –0.313, p >

0.10) possibly because of the great variety in the natureof the organic debris (e.g. sticks, leaves, live plants).

3.3. Statistical analyses

CART analyses indicated that water temperature wasthe dominant factor predicting the presence andabundance of Austrocrangonyx n.sp. in the study area,both in the regional study and local study (Figure 2). Itwas the only environmental variable measured whichcorrelated significantly with amphipod abundance (r =–0.4077, p > 0.01). Other influencing factors includedaltitude, CPOM (the second highest correlation coef-ficient, r = 0.2494, but not significant at p = 0.05),percent carbon and substrate.

Principal components biplots showed that acomplex multidimensional network of environmentalvariables was interacting with amphipods in the studyregion and also among themselves (Figures 3 and4). Goodness of fit of the regional biplot was 44.7%and for the local study biplot was 52%, so onlyhalf the data gathered during these studies could beexplained by the two-dimensional matrix provided bythese biplots.

In the regional study (Figure 3) stream width,depth and pH were all inversely related with alti-tude. Likewise vegetation and percent foliage coverwere both inversely related with stream temperature.Also substrate size decreased with increasing alti-tude and percentage carbon and dissolved oxygenwere inversely associated. There was apparently nocorrelation between temperature and altitude, or withsubstrate size and vegetation community. Positiveamphipod sites fell mainly in the righthand quad-rants, particularly the upper right quadrant, indicating

an association with higher CPOM, vegetation type,foliage cover, and low temperatures (Figure 3).

In the local study where sites were located sequen-tially along the Guy Fawkes River, environmental vari-ables interrelated differently (Figure 4). Direct corre-lations were apparent between altitude and vegetationcommunity, and between CPOM and temperature. Inaddition these respective pairs of correlated environ-mental factors were inversely related to each other,such that as altitude and vegetation community rankbecame higher, the level of CPOM and temperaturedecreased. Other direct correlations were identifiedbetween substrate and dissolved oxygen, and betweenvelocity, percentage carbon and width.

The biplot for the local study (Figure 4) alsoshows distinctions between stations and sites alongthe river. The robust ellipses included all of the sitesfor stations 1, 4 and 5, but there was intrastationvariability at stations 2, 3 and 6. Nevertheless it isclear that different factors assume dominance at thevarious stations – stream morphology at 1, substrateat 2, dissolved oxygen plus decreasing substrate sizeand morphology at 3, altitude and decreasing morpho-logy at 4, altitude and vegetation at 5, and velocity andCPOM at 6. Stations 2–6 had amphipods.

3.4. Results of experiments

In the colonization experiment, amphipods wereobserved to colonize leaf packs at all stations, exceptpasture (Table 3). In the survival experiment meansurvival far exceeded the mean mortality, with survivalgreatest at the wet eucalypt station and least at thepasture station (Table 3). In that no container returneda combined (alive + dead) total of 50 amphipods, therewas an unexplained mean loss of 32%. This was notdue to wall failures or escape holes, but could havebeen due to live amphipods eating the dead ones.

4. Discussion

Austrocrangonyx n.sp. lives in the headwaters ofstreams on the Ebor-Dorrigo region of the NewEngland tablelands. Other species of Austrocrangonyxalso live in headwater streams of the New Englanduplands, but at a southerly extension, the BarringtonTops region (Adlem & Timms, 2000). These speciesall prefer the cool waters of closed forests at altitudes>1100 m (Adlem & Timms, 2000). Most other fresh-

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Table 1. Temperature means, maxima and mean diurnal ranges (in ◦C) from data loggers atthree sites during February 1999.

Guy Fawkes Guy Fawkes Deer Park Creek

Rainforest Pasture Tea-tree

(Alt. = 1330 m) (Alt. = 1298 m) (Alt. = 1100 m)

Mean ± STDev 13.2 ± 0.7 16.0 ± 1.2 14.9 ± 1.7

Maximum 16.0 21.1 22.3

Mean Diurnal Range ± STDev 1.1 ± 0.8 2.6 ± 1.3 3.5 ± 2.2

Table 2. Relation between amphipods and CPOM in five riparian vegetation types in theEbor-Dorrigo region.

Vegetation Stations with amphipods Stations without amphipods

type number Dry CPOM number Dry CPOM

mean ± STDev Mean ± STDev

1. Pasture 2 154.9 ± 8.9 8 26.7 ± 32.6

2. Dry Sclerophyll 0 5 103.7 ± 86.6

3. Tea-tree 4 158.4 ± 100.9 1 28.4

4. Wet Sclerophyll 5 46.5 ± 45.7 5 9.7 ± 7.2

5. Rainforest 12 134.7 ± 111.1 7 74.3 ± 62.1

Figure 2. (a) Classification tree predicting the presence of Austrocrangonyx n.sp. in the regional study (0 means absence and 1 indicatespresence of Austrocrangonyx n.sp.). (b) Regression tree predicting the abundance of Austrocrangonyx n.sp. in the regional study. (Abundanceis indicated as individuals in a minute’s collection.) (c) Regression tree predicting the abundance of Austrocrangonyx n.sp. in the local study onGuy Fawkes River (Interpretation as in Figure 2b).

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Figure 3. Principal components biplot of sampling sites, amphipod distribution and environmental factors from the regional study. Interpretationfollows Gabriel (1971) in which the centre of each biplot represents the mean value of all the variables, length of each arrow is proportional tothe variability of the factor it represents, and the closer the arrows are together (or at 180◦) then the nearer their correlation coefficient is to 1(or –1). Sites with amphipods solid ovals, sites without amphipods open ovals.

Figure 4. Principal component biplot of sampling sites, amphipod abundances and environmental factors in the local study. Intrepretation as inFigure 3, except station numbers 1–6 sequentially upstream. The eclipses characterized each station, though for some stations (2 and 3) someindividual collections fell well outside station parameters indicating a degree of heterogeneity.

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Table 3. Comparative numbers of amphipods in various habitats in two experimentaltreatments in Upper Guy Fawkes River.

Pasture Tea-tree Wet Rainforest

Sclerophyll F

Colonization Experiment 0 ± 0 66.7 ± 1.7 69.3 ± 2.2 30.0 ± 2.5

Survival Experiment 24.7 ± 2.2 31.3 ± 5.7 41.7 ± 7.6 32.3 ±4.0

(initial n = 50)

water amphipods known in NSW also occur at rela-tively high altitudes – Neoniphragus spp. at BarringtonTops (at 1425 m) (Adlem & Timms, 2000) and atKoscuiszko (at ca 2000 m) (Williams & Barnard,1988; Hancock et al., 2000), and Pseudomoera spp.in the BarringtonTops and adjacent areas (>920 m)(Adlem & Timms, 2000). However Austrochiltoniasubtenius, a widespread species in southern Australia(Lim & Williams, 1971) occurs at sea level in southernNSW (Timms, 1997) and in southeastern NSW gener-ally (Timms, unpublished data).

The core area of distribution of Austrocrangonyxn.sp. is ca 135 km2 and when areas in which thedistribution is patchy are added, the known total areais about twice this. While no amphipods were foundbelow 1165 m, and were also absent from deforestedareas above this altitude, it is not readily apparentwhy amphipods could not be reliably found in forestedstreams outside the core area above 1165 m in suchstreams as the Little Murray R, Bangalow Ck and DeerPark Ck to the east and in the Styx R and Georges Ckto the south. Since almost all of these sites were insecondary regrowth forest, it is suggested there is ahistorical reason for the absence of amphipods relatedto clearing in the past and no recolonization. In thisrespect crustaceans often have poor dispersal powers,so that populations in adjacent streams can be distinctwith no apparent migration between them (Wools-chot et al., 1999; Hughes et al., 1995) In the caseof Austrocrangonyx n.sp. its suggested poor dispersalpowers are further checked by higher stream tempera-tures at lower altitudes, so that it simply cannot survivedownstream drift in order to move upstream to a newlocation.

The absence of amphipods from sites on graniteand >1165 m in the Cathedral Rocks National Parkmay be due either to the unsuitable open eucalyptforest as riparian cover and/or the stream bed of graveldid not trap enough CPOM. Although streams in bothareas looked permanent, most were small and perhaps

may dry in drought years, so that absences may also beattributed to the occasional lack of water since amphi-pods have no dessication resistant stage (Williams,1980).

The distribution of Austrocrangonyx n.sp. in theEbor-Dorrigo area is best predicted by low streamtemperatures and high percentages of carbon fromCPOM. Furthermore high regional abundances arebest predicted by low temperatures alone, though thegreatest abundances were from moss beds (Brown,1999). The latter result is not unexpected, as amphi-pods are often more abundant in macrophytes (e.g.Marchant, 1981; Adlem & Timms, 2000). Moregenerally, larger substrates, food supply and lowvelocities are typical controlling factors in amphipodmicrohabitat selection (Williams & Moore, 1986).While these factors were not identified in the regionalstudy (stream velocities were not measured), foodsupply, measured here as CPOM, was implied in thelocal study. In nearby Barrington Tops, Adlem &Timms (2000) found that the distribution and abund-ance of Austrocrangonyx spp. was most influencedby altitude (i.e. low temperature), flow rate and pH.This agrees in part with the present study when it isrealised that Adlem & Timms did not study CPOM orpercent carbon as factors, and pH is a factor correlatedwith altitude at Barrington Tops. This is because manystreams there emerge from Sphagnum swamps at highaltitude and then become less acid as they descendacross basalt.

While temperature and CPOM have been high-lighted as major factors affecting Austrocrangonyxn.sp. distribution and abundance, a multidimensionalnetwork of factors act in concert. In the local studyhigher altitude and vegetation community rank pluslower levels of CPOM, temperature, stream morpho-logy rank and substrate size are clearly associated withthe upper reaches of the stream. In comparison, down-stream stations show affiliation with higher valuesof velocity, temperature, CPOM (but not at pasture

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stations), stream morphology rank and substrate size,plus low values of altitude and vegetation.

Temperature, vegetation community type, percent-age foliage cover and CPOM are also strongly inter-correlated (Figure 3), as might be expected (Allan,1995). This is because higher ranked vegetationcommunities, such as rainforest, are denser and there-fore provide more shade and leaf litter, while alsoreducing sunlight intensity and stream temperatures.Stream temperatures were not however directly corre-lated with altitude as might be expected (e.g. Nebeker,1971), since open communities (i.e. pasture) whichallow stream warming now occur at various altitudes.Besides explaining the differences between stationsobserved in the data logger results (Table 1), in themultivariate analyses it is temperature that emerges asthe significant factor, not altitude.

In the local study (Figure 4), CART analysisimplied that low percentage carbon is associated withhigh amphipod abundances. However high densitiesof amphipods occur in moss beds (which have lowlevels of carbon) in both studies, so it seems that mossfunctions more as a habitat than as a food source.This suggestion could explain why amphipods are ableto survive at the pasture station (Station 1) duringthe survival experiment because adequate habitat wasprovided by the CPOM. Therefore it is possiblethat insufficient input of CPOM into stream pasturereaches prevents amphipods from living there. Thefact that amphipods were found at two such siteswith larger than normal CPOM adds weight to thisconclusion.

As noted above there is a clear distinctionbetween sampling sites of forested headwater andpasture reaches. Forested headwater reaches areconsistently grouped together by the regional studyCART analysis, and are usually characterised by lowtemperatures and high CPOM. Together these factorsaccount for the greatest percentage of amphipodabundance. Adlem & Timms (2000) identified similarrelationships with Austrograngonyx barringtonensisin the nearby Barrington Tops, as did Marchant (1981)for Gammarus amphipods in the northern hemisphere.These studies are consistent with the River ContinuumConcept, where shedder feeding groups are associ-ated with these forested, food-rich (CPOM) environ-ments. Amphipod populations were not recorded inthe regional Ebor-Dorrigo study at pasture sites; thesecommonly displayed higher temperatures and littleCPOM, conditions unfavourable to amphipod colon-isation. However the survival experiment suggested

that amphipods could survive (at least for shortperiods) at pasture stations, if CPOM was provided. Sowhile higher temperatures are important at the macro-scale, the lack of CPOM for shelter and food is prob-ably more important at the microscale, as suggestedabove. This is in agreement with the known biologyof many cold-water stenotherm amphipods which takeadvantage of large amounts of CPOM in forestedstreams for food and shelter (Marchant, 1981; Gee,1982; Holomuzki & Hoyle, 1990).

The retention of riparian vegetation along streamsis thus of overriding importance to the maintenanceof amphipods (and other invertebrates) in uplandstreams, as Quinn & Hickey (1990) point out in astudy in New Zealand. We believe that the whole-sale clearing of vegetation in the settlement of theEbor-Dorrigo area in the mid 1800s and the morerecent clearing in the late 1900s has severely restrictedthe distribution of amphipods. They do not survivein pasture sites because of elevated stream tempera-tures. The reversion of some of the more recentlycleared uplands to forest and accompanying coolerstream temperatures with adequate CPOM has notbeen accompanied by recolonisation of amphipodsbecause of their poor dispersal powers.

Presently land management in the area is vested inthe NSW National Parks and Wildlife Service, NSWState Forests and various private landholders. Thereis no tree clearing in National Parks, but there islimited tree felling in State Forests and in private landholdings, but in general accordance with the NSWVegetation Conservation Act 1997 on tree felling. Thisstatus quo needs to be maintained or more streams willbecome degraded.

Acknowledgements

This work is based on an Honours thesis by KBsupervised by BT. We are grateful for the hospitalityand support of landowners, especially the Rosenbergs,and we thank John Bradbury for identification ofamphipods, Bob Gittins for statistical advice, MartyHancock for loan of the data loggers and for criticallyreviewing the manuscript, and many friends and rela-tives for field assistance and support. The suggestionsby two anonymous referees are much appreciated.

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Table 4. Appendix 1. Amphipod counts and environmental data from sites investigated in the Ebor-Dorrigo region.

Locality Site ID no./min Altitude Substrate Morphology Width Depth Veg Com % Cover CPOM % Carbon Temp. pH Cond Turbidity DO

UGF1∗ LS1 0 1298 12.6 1.4 3.5 0.28 1 0 5.5 10 11.3 7.3 0.02 16 8.1UGF2∗ LS2 20 1312 11.5 1.4 3.8 0.18 3 75 8.8 27 9.5 7.3 0.017 8.4 8UGF3∗ LS3 4 1320 12 1.4 4.2 0.2 4 60 20.2 20 13.2 7.1 0.018 4 8.9UGF4∗ LS4 4 1330 12 1.3 4.2 0.2 5 60 23.2 34 12.6 6.9 0.02 4 8.4UGF5∗ LS5 10 1335 12 1.3 5 0.2 5 90 19.4 31 8.5 7.4 0.022 8 8.4UGF6∗ LS6 4 1460 11 1 2.5 0.1 5 100 164 24 10.3 6.9 0.022 8 8.5AW1 1 0 1215 12 1 4.9 0.2 1 0 33 47 20.6 6 0.022 0 8AW2 2 0 1205 7 2 4.8 0.4 1 0 73 25 23.6 6.1 0.019 0 8AW3 3 65 1295 12 1 4.6 0.1 4 75 17 31 17.6 6 0.023 0 8AW4 4 1 1300 11 2 8.3 0.7 5 90 307 20 13.1 6.2 0.023 0 8AW5 5 52 1298 11 1 4.5 0.1 5 60 33 68 16 6 0.024 0 8AW6 6 0 1284 14 1 6.6 0.3 4 30 11 11 14.6 5.6 0.024 4 8AW7 7 0 1285 15 1 8.3 0.6 5 70 161 29 14.6 5.6 0.025 15 10AW8 8 0 1095 14 2 12.9 0.3 4 60 9 95 15.5 8.1 0.025 0 9AWHW 9 95 1355 11 1 4.1 0.2 5 100 67 31 12.4 8 0.021 19 9BGW1 10 0 1108 14 1 4.9 0.4 4 30 9 86 18.1 8.1 0.02 12 8DPC4 11 20 1165 11 1 1.5 0.1 5 100 152 14 10.9 7.2 0.02 0 9FDC1 12 0 1190 13 1 6.1 0.2 5 70 109 28 14.1 7.6 0.022 0 9FDC2 13 0 1170 14 1 6.2 0.2 5 30 121 9 14.3 7.6 0.022 0 8FDT1 14 3 185 10 2 1 0.9 5 100 154 37 14.4 7.6 0.036 0 5FTD2 15 0 1320 11 1 0.3 0.1 5 100 42 24 15.1 7 0.024 14 8.3FDT3 16 189 1295 10 1 1.7 0.1 5 10 175 1 12.5 7.2 0.02 18 8.1GGC1 17 0 1308 12 1 3 0.2 3 20 28 27 22.5 6 0.02 12 8.1HLC1 18 0 1210 15 1 1.9 0.3 1 10 0 0 15.5 7.6 0.037 6 9.3MC1 19 11 1255 13 1 4.2 0.2 4 70 63 52 14.2 5.9 0.018 4 7.2MC2 20 4 1345 7 2 1.6 0.1 4 100 119 20 13.1 4.7 0.026 3 8.4MC3 21 1 1246 14 2 5.7 0.4 4 60 4 68 14.7 6.4 0.018 3 8.3MC4 22 0 1246 14 4 5.7 0.6 4 60 0 0 14.7 6.4 0.027 33 7.6MC5 23 5 1212 12 1 4 0.2 1 0 161 16 16.4 8.1 0.017 22 7.2MC6 24 96 1219 13 1 3.9 0.3 3 75 246 21 15.7 8.1 0.015 0 7.5MC7 25 0 1168 13 1 4.7 0.3 1 0 74 26 18.6 7.9 0.023 22 7.5MCHW 26 3 1348 13 1 2.5 0.1 5 90 22 40 14.3 4.4 0.018 3 7.5MCS2 27 0 1400 15 3 2.2 0.1 5 90 0 0 14.4 8 0.024 3 8.3MJC1 28 0 1238 14 1 4.2 0.4 1 0 1 57 18.1 7.7 0.023 4 8.4MJC2 29 0 1155 14 1 5 0.6 1 90 1 84 22 7.8 0.02 3 7.1MJHW 30 126 1361 9 1 3.7 0.1 3 100 127 17 11.6 6.8 0.011 4 6.2MLD1 31 0 1200 11 1 3.9 0.1 2 30 331 10 15 7 0.014 3 7.4NDC1 32 0 1320 5 1 1 0.1 3 100 30 57 18.4 6.4 0.012 2 7.5OKR1 33 0 1330 9 2 0.8 0.3 2 0 70 4 19.8 6.5 0.026 2 9.2RC1 34 0 1300 15 1 7.7 0.1 1 0 0 0 20.6 6.7 0.033 14 6.8SNC1 35 0 1370 1 1 1 0.1 2 10 101 76 16.1 6.6 0.017 0 7SNC2 36 0 1365 1 1 3 0.3 2 25 7 40 21.1 7.1 0.024 6 7.8SPT1 37 21 1385 11 1 1.1 0.2 5 15 357 23 12.3 7.2 0.018 4 7.6STR1 38 0 1395 12 1 2 0.1 5 80 87 22 15 7.5 0.016 4 7.2STR2 39 0 1380 11 1 2.5 0.1 4 60 30 57 15.6 7.4 0.02 16 8.1STR3 40 0 1335 8 1 4.3 0.3 1 0 149 14 13.3 6.6 0.02 16 8.1UGT1 41 181 1335 9 1 3.7 0.2 5 100 140 24 10.8 7.5 0.021 8 8.8WRS1 42 0 1515 12 3 0.2 0.1 5 100 0 10 14.1 7.5 0.021 8 8.8LMR∧ 43 0 1160BA1∧ 44 0 1135BA2∧ 45 0 1220DP1∧ 46 0 1170DP2∧ 47 0 1220

∗Values on Upper Guy Fawkes River are means of 8 subsites.∧These stations added in summer of 1999 are not included in most analyses.

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References

Adlem, L. T. & B. V. Timms, 2000. Biogeography of the FreshwaterPeracardia (Crustacea) from Barrington Tops, NSW. Proceedingsof the Linnean Society of New South Wales 122: 131–141.

Allan, J. D., 1995. Stream Ecology. Structure and Function ofRunning Waters. Chapman and Hall, London.

Bell, J. F., 1996. Application of classification trees to the habitatpreference of upland birds. Journal of Applied Statistics 23: 349–359.

Boulton, A. J., I. J. Kneipp, A. P. Smith & B. J. Sullivan, 1995.Aquatic Environment Report. Walcha/Nundle & Styx RiverManagement Areas EIS – Supporting Document No.3. StateForests of NSW, Pennant Hills, NSW.

Breiman, L., J. H. Friedman, R. A. Olshen & C. J. Stone, 1984. Clas-sifcation and Regression Trees. Wadsworth International Group,Belmont, California.

Brown, K. J., 1999. The environmental ecology of Austrocrangonyxnew species (Crustacea: Amphipoda in New England NSW,with reference to riparian clearing. B. Env.Sc. (Hons) thesis.University of Newcastle, NSW.

Chessman, B. C., 1995. Rapid assessment of rivers using macroin-vertebrates: A procedure based on habitat-specific sampling,family level identification and a biotic index. Australian Journalof Ecology 20: 122–129.

Fahey, E., 1976. The Settlement of Guy Fawkes and Dorrigo.Central North Coast Newspaper Company, Coffs Harbour, NSW.

Gabriel, K. R., 1971. The biplot graphic display of matrices withapplication to principal component analysis. Biometrika 58:453–467.

Gee, J. H. R., 1982. Resource utilisation by Gammarus pulex(Amphipoda) in a Cotswold stream: A microdistribution study.Journal of Animal Ecology 51: 817–832.

Growns, I. O. & J. A. Davis, 1991. Comparison of the macroin-vertebrate communities from streams in logged and undisturbedcatchments 8 years after harvesting. Australian Journal of Marineand Freshwater Research 42: 689–706.

Hancock, M. A., B. V. Timms, J. K. Morton & B. A. Renshaw, 2000.The structure of littoral invertebrate communities of four alpinelakes, Kosciuszko region, Australia. Proceedings of the LinneanSociety of New South Wales 122: 69–77.

Hughes, J. M., S. E. Bunn, D. M. Kingston & D. A. Hurwood,1995. Genetic differentiation and dispersal among populationsof Paratya australiensis (Atyidae) in rainforest streams in south-east Queensland, Australia. Journal of the North AmericanBenthological Society 14: 158–173.

Holomuzki, J. R. & J. D. Hoyle, 1990. Effect of predatory fish pres-ence on habitat use and diel movement of the stream amphipod,Gammarus minus. Freshwater Biology 24: 509–517.

Lim, K. H. & W. D. Williams, 1971. Ecology of Austrochiltoniasubtenuis (Sayce) (Amphipoda: Hyalellidae). Crustaceana 20:19–24.

Marchant, R., 1981. The ecology of Gammarus in running water.In: Lock, M. A. & D. D. Williams (eds), Perspectives in RunningWater Ecology. Plenum Publishing Corporation, New York: 225–249.

Marchant, R., 1989. Freshwater invertebrate survey method andanalytical techniques. In: Wetlands: Their Ecology, Function,Restoration and Management. Proceedings of the AppliedEcology and Conservation Seminar Series, Wildlife Reserves

held October–December, 1989. La Trobe University, Victoria:21–23.

Mather, G., 1991. Conservation Value of New South Wales Rivers –Guy Fawkes, Clyde and Macquarie. Total Environment Centre,Sydney.

Nebeker, A. V., 1971. Effect of temperature at different altitudes onthe emergence of aquatic insects from a single stream. Journal ofthe Kansas Entomological Society 44: 26–35.

Quinn, J. M. & C. W. Hickey, 1990. Magnitude of effects ofsubstrate particle size, recent flooding and catchment devel-opment on benthic invertebrates in 88 New Zealand rivers.New Zealand Journal of Marine and Freshwater Research 24:411–427.

Reed, J. L., I. C. Campbell & P. C. E. Bailey, 1994. The rela-tionship between invertebrate assemblages and available food atforest and pasture sites in three south-eastern Australian streams.Freshwater Biology 32: 641–650.

Ripley, B. D. & W. N. Venables, 1994. Modern Applied Statisticswith S-PLUS. Springer-Verlag, New York.

State Forests, 1995. Proposed Forestry Operations in the DorrigoManagement Area, Volume A: Interim (three year) Environ-mental Impact Statement – Main Report. State Forests, Sydney.

Stone, M. K. & J. B. Wallace, 1998. Long-term recovery of a moun-tain stream from clear-cut logging: The effect of forest succes-sion on benthic invertebrate community structure. FreshwaterBiology 39: 151–169.

Storey, A. W., D. H. D. Edward & P. Gazey, 1991. Surber and kicksampling: A comparison for the assessment of macroinverteb-rate community structure in streams of south-western Australia.Hydrobiologia 211: 111–121.

Swain, R., A. M. M. Richardson & P. A. Serov, 1993. An Eval-uation of the Potential of Litter Bags for Assessing the Effectof Forestry Practices on Stream Processes. Tasmanian ForestResearch Council, Research Report No. 7. Tasmanian ForestResearch Council, Hobart.

Timms, B. V., 1997. Study of coastal freshwater lakes in southernNew South Wales. Marine and Freshwater Research 48: 249–256.

Verbyla, D. L., 1990. Building predictive models from GeographicInformation Systems. In: LaBau V. J. and T. Cunia (eds),State-of-the-Art Methodology of Forest Inventory: A SymposiumProceedings, 30 July–5 August. Portland, Oregon: 403–408.United States Department of Agriculture, General TechnicalReport, Pacific Northwest, Number 263.

Wallace, J. B. & J. R. Webster, 1996. The role of macroinvertebratesin stream ecosystem function. Annual Review of Entomology 41:115–139.

Williams, D. D. & K. A. Moore, 1986. Microhabitat selectionby stream-dwelling amphipod; a multivariate analysis approach.Freshwater Biology 16: 115–122.

Williams, W. D., 1980. Australian Freshwater Life: The Inverteb-rates of Australian Inland Waters. Macmillan, Melbourne.

Williams, W. D. & J. L. Barnard, 1988. The Taxonomy of Crango-nyctoid Amphipoda (Crustacea) from Australian Fresh Waters:Foundation Studies. Records of the Australian Museum, Supple-ment No. 10.

Woolschot, L., J. M. Hughes & S. E. Bunn, 1999. Dispersal amongpopulations of Caridina sp. (Decapoda: Atyidae) in coastallowland streams, south-eastern Queensalnd, Australia. MarineFreshwater Research 50: 681–688.