Term Recolonization Patterns of Ants in Western Australian Rehabilitated

Journal of Long!term recolonization patterns of ants in Western Applied Ecology 0887\ 24\ Australian rehabilitated bauxite mines with reference to 050Ð071 their use as indicators of restoration success

J[ D[ MAJER and O[ G[ NICHOLS$ School of Environmental Biology\ Curtin University of Technology\ PO Box U0876\ Perth\WA 5734\ Australia^ and $Alcoa of Australia Ltd\ PO Box 141\ Applecross\ WA 5042\ Australia

Summary 0[ The return of invertebrate animals to rehabilitated mine pits is desirable for the re! establishment of ecosystem functioning[ A long!term ant monitoring programme is reported over 03 years in a jarrah Eucalyptus marginata forest control plot and in three bauxite mine pits\ one of which had been left unvegetated\ one planted with marri trees E[ calophylla and the other seeded with mixed native plant species[ 1[ The results con_rm published _ndings for the _rst 1 years of the succession that seeding with mixed species results in a more rapid attainment of a forest!like ant fauna\ although in the last 5 years of the study the ant fauna of the planted plot had become more similar to that of the seeded plot[ 2[ Changes in the nature of the ant fauna are described and it is concluded that although composition has substantially converged on that of the forest by the end of the study\ di}erences still persist[ 3[ Research on vegetation\ spiders and ants in bauxite mined areas which have been rehabilitated using more recent technology suggest that these di}erences will lessen with time and with the introduction of improved rehabilitation prescriptions[ 4[ An additional aim of the study was to validate the chronosequence approach to studying ecosystem recovery following disturbances such as mining[ It is concluded that long!term studies provide important information that is missed by the chrono! sequence approach[ Ideally\ rapid!feedback chronosequence approaches should be augmented by long!term case studies[ Key!words] Ants\ Formicidae\ long!term monitoring\ succession[ Journal of Applied Ecology "0887# 24\ 050Ð071

ern Australia "WA#\ completion criteria are not for! Introduction mally nominated but appear in various conditions of A commonly accepted goal of the rehabilitation of project approval under three classes of controlling mined land is to restore the structure\ diversity\ func! acts\ namely] the Environmental Protection Act tion and dynamics of the disturbed ecosystem\ all of "EPA# 0875^ the Mining Act "0867# as amended^ and which are attributes in which invertebrates play a piv! various agreement acts which pertain to the project otal role "Wilson 0876^ Erwin 0880#[ In the past\ the being developed "Mills\ Chandler + Caporn 0881#[ technology required to meet these goals has been Few regulatory bodies have formulated criteria for derived from experience\ although research over the the later stages of bond release and\ to the authors| past three decades into rehabilitation technologies has knowledge\ none require the re!establishment of resulted in considerable advances in such procedures[ adequate invertebrate communities to be taken into The need to carry out high!quality rehabilitation has account[ The latter may partly result from the auth! become more acute in the industry with the phasing orities not fully recognizing the importance of invert! in of performance standards and completion criteria ebrates in ecosystem functioning[ Inclusion of invert! "Mills\ Chandler + Caporn 0881#[ In some mining ebrate assessments is hindered by the lack of long! industries bonds are payable which are not returned term studies on which to assess whether rehabilitation Þ 0887 British until adequate rehabilitation\ which meets prescribed has been successful or not[ This generally results from Ecological Society completion criteria\ has been demonstrated[ In West! the absence of a long!term commitment to funding

050 051 rehabilitation research\ and attempts to circumvent marginata forest of south!west WA[ Following the Ant recolonization the problem are often made by sampling a range of de_nition of ore bodies\ the timber is harvested and of bauxite mines rehabilitated areas representing di}erent ages[ This the remaining vegetation is cleared from the required method\ which Twigg\ Fox + Luo "0878# and Fox area[ The top 049 mm of topsoil is then removed and\ "0885# refer to as the chronosequence approach\ pro! where possible\ is replaced directly onto an area being vides rapid feedback but can produce ambiguous data[ rehabilitated "prior to 0865 all topsoil was stockpiled#[ It makes the possibly incorrect assumption that sites The remaining overburden "up to 0 m# is removed and only di}er in terms of age\ although there may also stockpiled[ The cap rock is then blasted or ripped have been changes in the rehabilitation technology and the ore is removed to an average depth of 3=4 m[ over the time!scale represented by these plots "Majer Overburden and topsoil are returned and the com! 0874#[ It is therefore preferable that permanent plots pacted pallid clay zone is ripped to a depth of ¼ 0=4 m be established in representative areas and monitored to enhance water in_ltration and root penetration\ over the long!term in order to validate the chrono! and to reduce erosion[ sequence approach\ and also to provide more reliable Methods for rehabilitation of bauxite mine pits are feedback on the success of di}erent rehabilitation pro! currently evolving[ The earlier attempts utilized hand! cedures[ planting of nursery!reared Eucalyptus spp[ that are In view of their important role in the developing resistant to dieback disease Phytophthora cinnamomi\ ecosystem\ it is essential to understand how invert! such as E[ microcorys\ E[ resinifera\ E[ saligna and ebrate communities are developing in rehabilitated E[ maculata from eastern Australia\ and included no areas[ In 0864 a study was initiated on the reco! understorey component[ The current procedure uses lonization of invertebrates in three bauxite mined only native jarrah forest tree and understorey species[ plots in the south!west of WA[ One plot was planted In the mid!0879s there was a shift to direct!seeding\ with a single Eucalyptus species\ one was seeded with rather than replanting[ The procedure now follows mixed native vegetation and the other was unveg! the sequence of pit reshaping\ overburden and topsoil etated[ Majer "0870# reported on the initial 1 years of return\ ripping and spreading of seed and fertilizer in recolonization and concluded that seeding of mixed the pit[ The results of these two broad rehabilitation over! and understorey allowed for the return of con! approaches are quite di}erent[ The planted mine pits siderably more ant species than by simply planting a initially have the appearance of a plantation\ whereas tree monoculture\ where ant richness was only slightly direct seeding produces a regrowth of high structural greater than in the plot where no revegetation had and species diversity[ been established[ Pitfall trap catches indicated that the seeded plot also had the most abundant ant popu! SAMPLE SITES lations\ the greatest number of other epigaeic invert! ebrates and an ant fauna which\ in terms of its species A single example of each rehabilitation approach was composition\ was most similar to that of the forest selected for study[ Replication of plots was decided control plot[ Once again\ the planted plot was inter! against so that greater attention could be paid to suc! mediate between the seeded and unvegetated plot in cessional and seasonal trends within the study areas^ terms of all of these parameters[ These _ndings were the earlier chronosequence study "Majer et al[ 0873# subsequently supported by the results of short!term provided information about the variability of trends chronosequence!type studies of ants and Collembola between rehabilitation treatments[ Most of the work in 29 bauxite mines and three forest controls "Majer was conducted in the Del Park mine\ near Dwellingup et al[ 0873^ Greenslade + Majer 0882#[ "21>32?S\ 005>93?E# and in the Jarrahdale No[ 1 mine The three rehabilitated plots and the forest control "21>19?S\ 005>96?E#[ have been intermittently resampled until 0878[ This A 1 ha area at Del Park planted with a single paper describes these results and provides data that indigenous tree species "marri\ Eucalyptus calophylla# complement the _ndings from the short!term chrono! in June 0865 was selected as an example of the planting sequence study performed in the same area in 0867:68 approach[ An 07 × 07!m area was marked out in the "Majer et al[ 0873#[ It also provides much needed centre and is referred to as the {planted plot|[ A information on how ant communities develop over a 099 × 099!m area\ 44 m north!east of the planted area longer time!frame in rehabilitated areas and enables was also selected[ With the exception of topsoil the results of the chronosequence approach to be vali! replacement and ripping\ no rehabilitation was carried dated[ out in this experimental area[ The 07 × 07!m centre of this area is referred to as the {unvegetated plot|[ It was not possible to select a seeded area at Del Park Methods so a 1!ha area was chosen at the Jarrahdale mine[ This Þ 0887 British area was seeded with 03 tree and shrub species\ planted Ecological Society\ REHABILITATION PROCEDURES Journal of Applied with an additional nine tree species[ The 07 × 07!m Ecology\ 24\ Bauxite is currently being mined by Alcoa of Australia centre is referred to as the {seeded plot|[ Although 050Ð071 Ltd at various sites in the northern jarrah Eucalyptus most plant species were from WA\ a number of them 052 were not local to the area[ Simultaneous samples were and density were recorded using a 0!cm diameter\ 1! J[D[ Majer + obtained from an 07 × 07!m {forest control| plot\ m long rod divided into 14!cm intervals[ The sample O[G[ Nichols ¼ 0 km east of the Del Park plots[ The forest control plot plus a 0=4!m surround was gridded out and 38 plot was prescription burnt in the spring of 0871 and rod placings were made at 2!m intervals[ The number 0889^ although records are not available\ it was also of contacts of vegetation touching the rod at each 14! burnt a few years prior to commencement of the study[ cm interval was counted[ The tree canopy situated The forest control and the original vegetation of the vertically above the rod was also recorded "Levy + three mine pit sampling areas corresponded to group Madden 0822#[ Percentage area cover of vegetation S of Havel "0864#[ The tree strata was predominantly was obtained by calculating the percentage of the 38 E[ marginata "jarrah# with some E[ calophylla[ The recordings which touched any plant[ This calculation midstorey included Banksia grandis\ Persoonia lon! was done for the total length of the rod to give an gifolia and Allocasuarina fraseriana[ Common under! overall percentage cover value and also for each 14! storey species in this vegetation type are Xanthorrhoea cm interval to construct a vertical pro_le of percentage preissii\ Macrozamia riedlei\ Lasiopetalum ~or! cover[ Percentage canopy cover was derived from the ibundum\ Adenanthos berbigerus and Phyllanthus caly! number of rod placings beneath the tree canopy and cinus[ tree height was measured with a clinometer[ Surveys A description of the four ant monitoring plots is were performed in October 0864 and September given in Table 0[ It should be noted that it was not 0866[ A photographic record of plot development was possible to standardize the mine plots for conditions maintained through to 0868 and repeated in 0884[ of topsoil replacement\ use of stockpiled topsoil\ and During September 0884 a resurvey of the vegetation distance from forest border[ Majer "0879# has dem! within each plot was made using the same procedures onstrated that direct ant invasion from adjacent but with the addition of an assessment of litter depth forest\ as opposed to invasion by alates\ falls o} to and a survey of native plant and alien weed species negligible levels by 14 m\ so none of the treatments richness within a 14 × 14 m area surrounding and are likely to be in~uenced by edge!e}ects[ including each plot[ Botanists working for the com! A further three supplementary plots were installed pany report that the structure of the vegetation in the in forest blocks near Dwellingup\ about 09 km south three rehabilitated plots had not changed appreciably of the Del Park mine in order to examine the varia! between 0878 "when the latest ant survey was carried bility in ant faunas between unmined jarrah forest out# and 0884\ although there had been an increase in sites[ These plots were situated in the Plavins\ Curara tree height and a thinning of the understorey in the and Pindalup forest blocks and all occurred in similar planted and seeded plots due to plant senescence "J[M[ forest types to that of the forest control[ Koch\ personal communication#[ In this paper\ In order to compare ant recolonization rates with nomenclature for plants follows Green "0874# and those recorded in sites rehabilitated using current nomenclature for ants follows Taylor\ Brown + Car! techniques\ data obtained during Alcoa|s ongoing dale "0874#[ rehabilitation monitoring programme were also con! sidered[ This monitoring was conducted in four

rehabilitated "carried out in 0889# and in four dieback SAMPLING METHODS "P[ cinnamomi#!free unmined jarrah forest control sites situated at the Jarrahdale and Huntly "an exten! A single grid of 5 × 5 pitfall traps spaced at 2!m inter! sion of Del Park# mines[ vals was established in a representative region of each of the four main and three supplementary plots[ Traps VEGETATION CHARACTERIZATION consisted of 07!mm internal diameter Pyrexþ test The vegetation characteristics were quanti_ed at each tubes set in the ground in plastic tubes to facilitate of the four ant monitoring plots[ Vegetation structure changing "Majer 0867#[ Traps contained 2 mL of

Table 0[ Description of the four plots used for the invertebrate succession study

Date Date Date Distance First area topsoil Topsoil planted from forest invertebrate Plot description Location cleared replaced stockpiled or seeded border "m# sampling date

Forest control Del Park NA NA NA NA NA March 0865 Unvegetated Del Park Early October Yes NA 114 March 0865 "DP8# 0861 0864 Planted with marri Del Park Early October Yes June 0865 069 June 0865 Þ 0887 British "DP8# 0861 0864 Ecological Society\ Seeded with mixed Jarrahdale Early April No July 0865 24 June 0865 Journal of Applied native species "JW 391:395# 0863 0865 Ecology\ 24\ 050Ð071 NA  Not applicable[ 053 alcohol:glycerol preservative[ After leaving the traps position[ Dissimilarity values greater than 9=77 were Ant recolonization in the ground for 0 week to minimize digging!in e}ects re!estimated using the shortest path algorithm of of bauxite mines "Greenslade 0862#\ they were uncorked for 6 days in PATN to minimize the asymptotic distortion intro! March or June 0865 "Table 0#[ The 6!day samples were duced by the Czekanowski measure[ Secondly\ the repeated at monthly intervals until the end of 0866\ association measure {two!step| "Belbin 0879# was used after which sampling intensity was reduced to four to determine the quantitative relationships between times per year\ with samples being taken at 2!monthly each pair of species based on their distribution across intervals[ Samples were taken from the four main plots sites[ An outline of the reasoning for selecting these over 5 of the remaining 01 years through until 0878^ procedures to detect di}erences in plot and com! sampling was discontinued in the three supplementary munity composition may be found in McKenzie\ Rob! plots in 0868\ 3 years after sampling commenced[ inson + Belbin "0880#[ Traps were returned to the laboratory for hand sorting For both measures of association\ a modi_ed ver! of the contents[ Ants were sorted to species level and\ sion of the {pair group arithmetic averaging|\ or where possible\ named[ Those which could not be UPGMA "Sneath + Sokal 0862^ Belbin 0878#\ hier! named were assigned species codes pertaining to the archical clustering strategy was used[ The clustering Australian National Insect Collection "ANIC# or Cur! parameter "Beta# was set to Ð 9=0 "see Belbin 0878#[ tin University "JDM# collection[ A full voucher col! There is no generally accepted method for determining lection is housed in the Entomology Laboratory at the optimum number of groups that should be dis! Curtin University[ tinguished from a dendrogram[ Consequently we cut At the eight sites selected to examine current the dendrograms horizontally at clearly visible gaps[ A rehabilitation\ 19 39!mm diameter pitfall traps set {two!way table| was also produced in which the 21 along a 099!m transect were opened for 6 days during plot!years and the 52 species of the data matrix were late!summer during 0881 and 0884\ when the mine re!arranged according to the species and the plot!year pits were 1 and 4 years old\ respectively[ Ants were classi_cations[ sorted and identi_ed using the same voucher col! In order to investigate the plot!year clustering in lection[ more detail and also to con_rm the robustness of the clusters\ the same data were ordinated in a three! dimensional space using semistrong hybrid scaling DATA ANALYSIS "Belbin 0880#[ A minimum!spanning tree was then Mean litter depth and tree height were calculated from superimposed upon the resulting ordination diagram the individual measurements and percentage ground to indicate plot!years most similar in terms of ant and canopy cover were derived from the Levy rod species composition[ Additionally\ in order to provide placings[ Plant species richness was derived from the a more simplistic representation of changes in ant total list of plant species from each plot and this was species composition in the rehabilitation\ the simi! used to calculate the degree of similarity between each larity of ant species composition in each of the three rehabilitated plot and the forest control[ Sorensen|s rehabilitated plots to that in the forest control during quotient of similarity "I# was used for this purpose the corresponding sampling year was calculated using and was calculated by the following formula] Sorensen|s quotient of similarity "I#[ The values for each plot were then graphed against sample year[ I 1c:"a ¦ b# Ant species were further classi_ed into functional where a and b are\ respectively\ the numbers of species groups according to their habitat requirements and in sites A and B\ and c is the number of species in perceived status in Australian ant communities using common[ the scheme described by Andersen "0889\ 0884#[ This The numbers of ants of each species per plot per scheme classi_es the ants as dominant Dolich! sample period were compiled[ In order to analyse tem! oderinae\ associated subordinate Camponotini\ cli! poral changes in ant fauna composition\ the data for mate specialists\ cryptic species\ opportunists\ gen! each individual species were graphed[ The data were eralized Myrmicines and specialist predators[ This then converted to presence:absence and then bulked aspect of the analysis was conducted on the groupings by individual years to produce a summary of the spec! of ant species derived from the ant species dendrogram ies present in each year[ This enabled graphs to be and also on the species present in the four plots in the drawn of actual and cumulative species richness per _nal year of sampling[ plot over the 03!year sampling period[ The matrices for the four plots were then amal! gamated to provide a matrix of 52 ant species × 21 Results plot!years[ The analysis package PATN "Belbin 0878# Þ 0887 British was used to seek patterns in the data matrix[ The Ecological Society\ HABITAT DEVELOPMENT Journal of Applied Czekanowski measure "Faith\ Minchin + Belbin 0876# Ecology\ 24\ was used to compare the plots from each year "plot! General views of the four ant monitoring plots during 050Ð071 years# according to similarities in their species com! 0868 and 0884 are shown in Fig[ 0[ The rehabilitated 054 J[D[ Majer + O[G[ Nichols

Fig[ 0[ General views of the three rehabilitated plots and the forest control in 0868\ 2 years after initial revegetation\ and in Þ 0887 British 0884\ 5 years after the last ant sampling period[ Ecological Society\ Journal of Applied Ecology\ 24\ 050Ð071 055 plots in 0884 di}er from those in 0878\ when the ants Ant recolonization were last sampled\ in that the trees have increased of bauxite mines in height and\ in the planted and seeded plots\ the understorey has thinned out[ Although the forest con! trol plot was prescription burnt in 0871 during the course of the study\ previous research indicated that the vegetation of the jarrah forest does not change much in response to prescription spring burns "Bell + Koch 0879#[ A summary of the vegetation charac! teristics in the four plots is given in Table 1 and the percentage plant cover pro_les for the latter two dates are shown in Fig[ 1[ Pro_les are not presented for October 0864 because the plants in the rehabilitated plots contributed virtually no cover[ The forest control contained 63 plant species "including one alien weed species# and\ during all sam! pling periods\ exhibited a well developed ground cover\ especially in the 9Ð64 cm range\ and a dense canopy cover "Table 1#[ Inspection of the cover pro! _les "Fig[ 1a# and the photographic record indicated that the forest plot had changed very little during the study period\ except that there had been an increase in understorey density[ The unvegetated plot was colonized by a few scat! tered weeds and native plants during the _rst 1 years\ although their cover was so low that it was not rec! orded by the Levy rod "Table 1\ Fig[ 1b#[ By 0884 this plot supported a few Eucalyptus spp[ established from wind!blown seed\ scattered native shrubs and a dense ground cover of weeds[ The major part of the plot was open ground covered in annual weeds\ the litter layer was thin and patchy and 15 plant species were present\ of which 00 were weeds[ The developing marri trees in the planted plot con! tributed modestly to ground cover by 0866\ although their mean height was only 9=5 m[ The plot had taken on a dense\ forested appearance by 0878 and\ in 0884\ canopy cover was over 59) and tree height almost 09 m "Table 1#[ The understorey was dense up to 1 m and the ground was virtually devoid of weeds "Fig[ 1c#[ The depth of the litter layer was similar to that of the forest and 28 species of plants were present\ of which 8 were weeds[ The understorey had thinned out since 0878\ leaving a number of dead stems of Acacia and other native shrubs[ By 0866 the seeded plot supported a dense under! storey\ with a few small emergent trees[ However\ in 0867 the plot was virtually impenetrable due to the dense understorey\ which has persisted through to 0884 "Table 1#[ The 0884 canopy cover was greater than in the forest control\ although the understorey had thin! Survey date October 0864Groundcover Canopy cover Tree height Ground September 0866 Canopy cover Tree cover Litter height depth Ground Canopy cover September 0884 cover Tree Species Species ned out over the last 09 years due to the death of short! lived shrubs such as Acacia extensa "Fig[ 1d#[ The dense shrub and tree strata in this plot produced a litter layer which was over three times as deep as in the forest Þ 0887 British control[ Of the three rehabilitated areas\ this plot sup!

Ecological Society\ Changes in plant structural attributes in the forest control and three rehabilitated minesite plots in the _rst two years of the study and in 0884[ Litter depth\ plant species richness and similarity of Journal of Applied ported the highest plant species richness "41 spp[\ with no weeds#\ although by 0884 it had still not attained Ecology\ 24\ Includes native and weed species[ Table 1[ Forest controlUnvegetatedPlantedSeeded 69 9 79 9 9 9 07=9 9 9 9=9 69 9=9 9=9 9 79 03 62 9 07=9 9 9 9=9 1=8 9=5 0=4 9=2 63 1=2 00=9 65 70 59 49 01 07=8 51 84 63 5=7 8=6 05=7 Ð 15 28 41 9=09 9=21 9=39 plant species composition to that in the forest control were only measured in 0884 050Ð071 the plant species richness of the forest control[ Study plot ")# ")# "m# ")# ")# "m# "cm# ")# ")# height"m# richness similarity 056 J[D[ Majer + O[G[ Nichols

Fig[ 1[ Plant percentage cover pro_les for the four study plots in September 0866 "ž# and September 0884 "r#[

In terms of plant species composition in 0884\ the richness in the planted plot increased to a level slightly seeded plot was most similar to the forest control\ the greater than that in the seeded plot[ unvegetated plot was least similar\ while the planted Inspection of the occurrence of individual species plot was intermediate between the two "Table 1#[ in the annual samples "Fig[ 4# indicates that variation in species richness between years can be caused by loss and:or recruitment of species in the plot[ Another ANT SPECIES possible reason is that continuously present species Overall\ 52 species from 13 genera were encountered may have been missed in some years and ser! in the four ant monitoring plots and all were typical endipitously sampled in others[ Although this of those found in pristine and:or disturbed areas undoubtedly happened\ it is not considered to be a within this part of the jarrah forest "J[ D[ Majer\ major factor in view of the high density of pitfall traps unpublished data#[ In total\ 41 species were sampled used "25 in 213 m1# "see Abensperg!Traun + Steven in the forest control plot\ 14 in the unvegetated plot\ 21 0884# and the fact that trapping was performed mon! in the planted plot and 28 in the seeded plot "Table 2\ thly and then\ in the last six samplings\ four times Fig[ 2#[ More detailed observations "Majer 0886# indi! per year "see Majer 0886#[ Thus\ the increase in the cate that these cumulative counts are a complete cen! cumulative number of species observed in the forest sus of the ant fauna in each of the individual plots\ control "Fig[ 2# is probably caused by the occasional although not all species present were obtained in an sampling of rare species or species which enter the plot individual sampling period[ The term species richness from adjoining areas and also from species turnover is therefore used here to indicate sample species rich! within the plot[ Overall\ despite the fact that 02 rec! ness[ The order of ranking of species richness between orded species were not sampled in the _nal year\ there plots was generally consistent throughout the entire appears to have been an increase in ant species rich! Þ 0887 British study period "Fig[ 3#\ although the di}erential between ness in the forest control between 0865 and 0878[ Ecological Society\ Journal of Applied the unvegetated and planted plots prior to 0870 was There was a steady increase in ant species richness Ecology\ 24\ considerably less than the di}erential between the in all three rehabilitated plots\ both in terms of num! 050Ð071 seeded plot and these two plots[ After 0873\ species ber of species sampled per year and also cumulative 057 Table 2[ Cumulative checklist of ant species sampled over the entire 03!year period in the rehabilitated mine and forest control plots Ant recolonization Rehabilitation of bauxite mines Unvegetated Planted Seeded Forest

PONERINAE Brachyponera lutea xxx Cerapachys sp[ JDM 194 x Heteroponera sp[ JDM 81 x x Hypoponera con`rua x xxx H[ sp[ JDM 521 x Lepto`enys sp[ JDM 77 x Rhytidoponera inornata x xxx R[ violacea xxx R[ sp[ JDM 010 x Trachymesopus rufoni`ra xxx MYRMICINAE Anisopheidole antipodum xx Cardiocondyla nuda xxx Cremato`aster sp[ 2 "ANIC# x x Meranoplus sp[ 00 "ANIC# x x M[ sp[ 01 "ANIC# x x x Monomorium sp[ 0 "ANIC# x x x x M[ sp[ 1 "ANIC# x x x x M[ sp[ JDM 099 x x x M[ sp[ JDM 091 x M[ sp[ JDM 087 x Pheidole lati`ena xxx P[ sp[ JDM 288 x Tetramorium impressum x T[sp[ 4 "ANIC# x x x x T[ sp[ 5 "ANIC# x T[ sp[ 8 "ANIC# x x x x FORMICINAE Camponotus michaelseni x xxx C[ obni`er gp[ x x x C[ sp[ 04 "ANIC# x x C[ sp[ JDM 52 x C[ sp[ JDM 095 x x C[ sp[ JDM 096 x x x C[ sp[ JDM 009 x x x C[ sp[ JDM 072 x C[ sp[ JDM 088 x x x x Melophorus sp[ 0 "ANIC# x x x x M[ sp[ 2 "ANIC# x x M[ sp[ 5 "ANIC# x M[ sp[ 6 "ANIC# x x M[ sp[ JDM 086 x M[ sp[ JDM 198 x x M[ sp[ JDM 110 x Paratrachina sp[ JDM 103 x Sti`macros sp[ JDM 47 x x x x S[ sp[ JDM 002 x x x S[ sp[ JDM 004 x x S[ sp[ JDM 264 x x DOLICHODERINAE Anonychomyrma sp[ JDM 241 x x A[ sp[ 08 ANIC# x x Dolichoderus sp[ JDM 100 x D[ sp[ JDM 522 x Doleromyrma darwinianus x xxx Iridomyrmex `reensladei x xxx I[ anceps gp[ 07 "ANIC# x x x x I[ occiduus x I[ bicknelli gp[ 10 "ANIC# x x x x I[ rufoni`er gp[ JDM 8 x I[ discors gp[ JDM 061 x x x x I[ anceps gp[ JDM 240 x I[ anceps gp[ JDM 242 x Þ 0887 British Ochetellus `laber gp[ JDM 72 x x x x Ecological Society\ Papyrus nitidus x Journal of Applied Tapinoma sp[ JDM 023 x x x Ecology\ 24\ Total species 14 21 28 41 050Ð071 058 their disappearance from the succession "e[g[ Cam! J[D[ Majer + ponotus obniger from the unvegetated and planted O[G[ Nichols plots\ Cardiocondyla nuda from the planted and seeded plots\ Iridomyrmex discors gp[ JDM 061 from the planted plot\ Iridomyrmex rufoniger gp[ JDM 8 from the seeded plot\ Melophorus sp[ JDM 198 from the planted plot and Monomorium sp[ JDM 091 from the seeded plot#[ Inspection of the time of initial appearance of indi! vidual ant species in the succession "Fig[ 4# indicated that they tended to arrive earliest in the seeded plot\ Fig[ 2[ Cumulative number of ant species sampled in the latest in the unvegetated plot and at an intermediate forest control and in the three rehabilitated minesites over time in the planted plot[ the 03!year sampling period] Â\ unvegetated minesite^ Á\ There were also di}erences in the pattern of abun! planted minesite^ ž\ seeded minesite^ Ž\ forest control[ dance of the smaller dolichoderines[ For instance Doleromyrma darwinianus and Ochetellus glaber gp[ JDM 72\ abundant in the forest\ were only present in low numbers in the unvegetated and planted plots\ although at somewhat higher levels in the seeded plot[ In view of their small size\ small nest population and non!aggressive behaviour\ these ants are unlikely to be in~uential on the rest of the ant fauna[ Of the mid! size dolichoderines\ the unvegetated plot was popu! lated by Iridomyrmex anceps gp[ 07 "ANIC# from year 0 onwards and by Iridomyrmex bicknelli gp[ 10 "ANIC# from year 7 onwards[ The pattern was similar in the planted plot except that I[ bicknelli gp[ 10 "ANIC# colonized at year 2 and I[ discors gp[ JDM 061 was common in the fourth and _fth years of the Fig[ 3[ Number of ant species sampled per year in the forest control and the three rehabilitated minesite plots over the 03! succession[ In the seeded plot I[ anceps gp[ 07 "ANIC# year sampling period] Â\ unvegetated minesite^ Á\ planted and I[ bicknelli gp[ 10 "ANIC# were both common minesite^ ž\ seeded minesite^ Ž\ forest control[ from the second year onwards and I[ rufoniger gp[ JDM 8 was common from years 1Ð3[ Probably the most signi_cant di}erence between plots was in the pattern of abundance of the large species richness "Figs 2 and 3#[ This represents an dolichoderine\ Iridomyrmex greensladei\ which was accession of species within the plots "Fig[ 4#\ although common in the unvegetated and planted plots from there may also be some loss of species from the earlier year 2 onwards[ This ant was uncommon in the seeded stages of the succession[ For instance\ in the _nal plot and was only sampled once in the forest[ This ant sampling year\ _ve of the species present in the unveg! is favoured by highly insolated ground "Greenslade etated plot in previous years were not found\ seven 0863#\ which is a characteristic of the unvegetated plot from earlier planted plot samples were not found and and of the early stages of the planted plot^ the rapid 05 from earlier seeded plot samples were not found establishment of ground cover in the seeded plot and "Fig[ 4#[ The majority of species not sampled in the the dense shade of the forest would have precluded its _nal year were ants that previously had been enco! establishment in these areas[ The abundance of this untered only sporadically and may either have been ant in the unvegetated and planted plots is of par! missed by the sampling programme or had been from ticular signi_cance since this species\ and its close rela! incipient colonies that had failed to establish[ Some tives "the meat ants#\ are known to in~uence the diver! were cryptic species or ants with small colony sizes sity and composition of other ant species occurring "e[g[ Hypoponera congrua in the planted and seeded close to their nests "Greenslade 0865^ Andersen + plots\ Brachyponera lutea in the seeded plot\ Stig! Patel 0883#[ macros sp[ JDM 47 in the unvegetated plot\ Stig! macros spp[ JDM 264 and 004 in the seeded plot\ FAUNAL COMPOSITION Tetramorium sp[ 4 "ANIC# in the planted plot\ Tetra! morium sp[ 5 "ANIC# in the seeded plot and Mer! Six groups of plot!years were produced by the UPGMA Þ 0887 British anoplus sp[ 01 "ANIC# in the seeded plot# that could dendrogram "Fig[ 5#[ Group a comprised the eight Ecological Society\ Journal of Applied easily have been missed in the _nal sampling year[ forest control plot!years\ group b the earliest seeded Ecology\ 24\ Others had been regularly sampled in earlier years and plot!year\ group c the mid!period seeded plot!years\ 050Ð071 their absence from the _nal sampling year suggests group d the later period plot!years from all three 069 Ant recolonization of bauxite mines

Þ 0887 British Ecological Society\ Journal of Applied

Ecology\ 24\ Numbers of ants sampled per 6!day trapping period over 03 years in "a# the forest control\ "b# the unvegetated minesite\ "c# the planted minesite and "d# the seeded minesite[ Samples were taken monthly 050Ð071 Fig[ 4[ during the _rst 1 yearsspecies and have then been at scaled 2!monthly against intervalsrehabilitated the during plot maximum are selected catch presented years for in until that the 0878[ species order The and in horizontal this which axis value they has is appear been presented in constructed at the to the succession[ left show hand clearly side the of sampling the times graph[ and Ants is in therefore the not control linear[ plot Graphs are of presented each in taxonomic order whereas those in the 060 J[D[ Majer + O[G[ Nichols [ Continued

Þ 0887 British Fig[ 4[ Ecological Society\ Journal of Applied Ecology\ 24\ 050Ð071 061 Ant recolonization of bauxite mines [ Continued

Þ 0887 British Fig[ 4[ Ecological Society\ Journal of Applied Ecology\ 24\ 050Ð071 062 J[D[ Majer + O[G[ Nichols [ Continued Fig[ 4[ Þ 0887 British Ecological Society\ Journal of Applied Ecology\ 24\ 050Ð071 063 Ant recolonization of bauxite mines

Fig[ 5[ Plot!years classi_ed by UPGMA dendrogram according to similarities in their ant species composition[ Group a  the eight forest control plot!years\ b  the earliest seeded plot!year\ c  the mid!period seeded plot!years\ d  the later period plot!years from all three rehabilitated areas\ e  the earliest planted and unvegetated plot!years and f  the mid!period unvegetated and planted plot!years[ See Table 3 for list of plot!years in each group[

rehabilitated areas\ group e the earliest planted and Consideration of trends on the dendrogram tends unvegetated plot!years\ and group f the mid!period to be complicated by the depiction of variations in site unvegetated and planted plot!years "Table 3#[ a.nities in the two!dimensional plane of the diagram Ten assemblages of species were produced by the "Fig[ 5#[ It is here that the three!dimensional ordi! corresponding UPGMA dendrogram of ant species nation of plot!years helps to visualize the nature of "Fig[ 6\ Table 3#[ Two of the largest assemblages "0 the relationships[ Figure 8 shows the results of the and 3# contained species which were ubiquitous to ordination\ on which plot!years with the greatest simi! both forest and rehabilitation[ Another large assem! larity of species composition are connected using the blage "2# contained species which were characteristic results of the minimum spanning tree analysis[ In of the forest\ the seeded plot and the later samples order to relate the ordination diagram to the plot! from unvegetated and planted plots[ Assemblages 1 year dendrogram "Fig[ 5#\ the six plot!year groups are and 4 contained forest species which were only once encircled on the diagram "Fig[ 8#[ found in the rehabilitation\ while assemblage 5 con! The clusters containing earliest period rehabili! tained exclusively forest species[ Finally\ assemblages tation "groups b and e# are the most separated from 6Ð09 contained species which were con_ned to\ and the other clusters[ These then {connect| into the largest characteristic of various ages of the rehabilitation^ group "group f# which represents the mid!period some of these species have been mentioned in the unvegetated and planted plot years\ although seeded paragraph concerning species which had apparently plot 0865 connects via seeded plot 0868\ which falls disappeared from the succession[ within group c[ Group f then connects to both group The functional group pro_les of the ant species c "the mid!period seeded plot!years# and group d "the within four main distribution categories "ubiquitous\ later period samples from all three rehabilitated plots#[ predominantly forest\ forest plus older rehabilitation Group d is the most closely allied to the group of and rehabilitation only# which were formed by amal! forest plot!years\ although the positioning of forest gamating some of the related assemblages are shown "group a# and group d rehabilitation plot!years is still in Fig[ 7[ Clear di}erences are evident\ with all seven clearly separate[ In summary\ the ordination diagram ant functional groups represented in the ubiquitous appears to represent a succession of plot!years from category\ six in the predominantly forest category and groups b and e to group f to group c or group d to _ve in each of the other two categories[ The ubiquitous forest group a[ category contains a reasonably even spread of species Figure 09 provides a more simplistic representation from all functional groups while the predominantly of the degree to which the ant fauna in three rehabili! forest category is represented by a high proportion of tated plots has started to resemble that of the forest climate specialists\ suggesting that they are par! control[ It should be noted that the degree of similarity ticularly sensitive to disturbance in the rehabilitated to the forest is never likely to reach one due to inherent areas[ A high proportion of cryptic species make up variability in ant species composition within undis! the forest plus older rehabilitation category\ while the turbed communities and also due to the serendipitous ants con_ned to rehabilitation contain a good rep! sampling of rare species[ For instance\ the three sup! Þ 0887 British resentation of dominant Dolichoderinae and gen! plementary undisturbed forests which were sampled Ecological Society\ Journal of Applied eralized Myrmicines which tend to be associated with yielded 17Ð27 species\ with a mean similarity of 9=52[ Ecology\ 24\ open conditions and which are tolerant of dis! Nevertheless\ the trends indicate that the ant fauna in 050Ð071 turbance[ all three plots becomes more like that of the forest 064 J[D[ Majer + O[G[ Nichols UUUUP UP P P SSSSS SSPPUU PU P ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ Group aFFFFFFFF66776767 S 56388079 6 5 66677 67890 777777 388383 66 b 55 6766667677 6976870890 c d e f ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ forest control plot  gp[ gp[ sp[JDM241 JDM 009 sp[ 2 "ANIC# sp[ JDM 81 sp[ 1 "ANIC# sp[ 0 "ANIC# sp[ 4 "ANIC# sp[ JDM 095 sp[ 01 "ANIC# sp[ 2 "ANIC#sp[ 00 "ANIC# sp[ 6 "ANIC# sp[ JDM 198 sp[ 5 "ANIC# sp[ JDM 086 sp[JDM77 sp[JDM004 sp[JDM002 Camponotus Brachyponera lutea Rhytidoponera violacea Meranoplus Monomorium Doleromyrma darwinianus Ochetellus `laber Tetramorium Monomorium Melophorus Camponotus sp[ Heteroponera Lepto`enys Sti`macros Anonychomyrma Meranoplus Camponotus obni`er Cremato`aster Sti`macros Melophorus Melophorus Melophorus Melophorus 1[ Þ 0887 British SpeciesAssemblage0[ Plot!years "codes printed vertically# ¦

Ecological Society\ Two!way table of ant species by plot!year[ The groupings are those derived from the plot!year dendrogram "Fig[ 5# and the ant species dendrogram "Fig[ 6#[ Plot!year codes are printed vertically[ Journal of Applied Ecology\ 24\

050Ð071 Table 3[ U  unvegetated plot^ P  planted plot^ S  seeded plot^ F Species Plot!years "codes printed vertically#

Group a b c d e f FFFFFFFF S SSSSS SSPPUU PU PUUUUP UP P P 66776767 6 66677 777777 66 6766667677 56388079 5 67890 388383 55 6976870890 2[ Hypoponera con`rua Pheidole lati`ena Camponotus sp[ JDM 096 Trachymesopus rufoni`ra Tapinoma sp[ JDM 023 Anonychomyrma sp[ 08 "ANIC# Monomorium sp[ JDM 099 Tetramorium sp[ 8 "ANIC# Sti`macros sp[JDM47 ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ 3[ Rhytidoponera inornata Camponotus micaelseni Camponotus sp[JDM088 Melophorus sp[ 0 "ANIC# Iridomyrmex anceps gp[ 07 "ANIC# Iridomyrmex bicknelli gp[10 "ANIC# Iridomyrmex discors gp[JDM061 Cardiocondyla nuda Iridomyrmex `reensladei ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ 4[ Rhytidoponera sp[ JDM 010 Camponotus sp[ JDM 52 Paratrachina sp[ JDM 103 Dolichoderus sp[ JDM 100 Papyrus nitidus Monomorium sp[ JDM 087 Iridomyrmex anceps gp[ JDM 240 Sti`macros sp[ JDM 264 Dolichoderus sp[ JDM 522 ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ 5[ Cerapachys sp[ JDM 194 Melophorus sp[ JDM 110 ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ 6[ Monomorium sp[ JDM 091 Tetramorium sp[ 5 "ANIC# Iridomyrmex occiduus gp[19 "ANIC# Iridomyrmex rufoni`er gp[ JDM 8 Iridomyrmex anceps gp[ JDM 242 ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ 066 J[D[ Majer + O[G[ Nichols

Fig[ 6[ Ant species classi_ed by UPGMA dendrogram accord! ing to their co!occurrences in the same plot!years[ See Table 3 for list of ant species in each assemblage[ control with the passage of time\ although the fauna of the seeded plot is most like that of the forest control in all but one of the years when sampling was done[ Up until 0870 there was no consistent di}erence in the degree to which the fauna in the unvegetated and planted plots resembled that of the forest\ although from 0873 to 0878 the fauna of the planted plot\ as opposed to that of the unvegetated plot\ became increasingly more similar to that of the forest^ indeed by 0878 it resembled the forest fauna to almost the same degree as the seeded plot[ When viewed in terms of ant functional groups\ di}erences in the pro_les were still evident between rehabilitated plots and the forest in 0878 "Fig[ 00#[ Although all functional groups were represented in the forest control\ specialist predators were not sam! pled in any of the rehabilitated plots[ The pro_le in the unvegetated plot was least similar to that of the forest in that it contained a high proportion of oppor! tunists and a lower representation of cryptic species and climate specialists[ With the exception of the ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ ¦ÐÐÐÐÐÐÐЦЦÐÐÐÐЦÐÐÐÐÐЦÐЦÐÐÐÐÐÐÐÐÐЦ absence of specialist predators and an under!rep! resentation of climate specialists\ the planted and seeded plots exhibited relatively similar pro_les to that of the forest[

Discussion

TRENDS AMONG PLOTS

Comparison of ant faunas in minesites with an unmined benchmark forest is confounded by at least sp[ 04 "ANIC# sp[ JDM 072 sp[ JDM 521 two problems[ First is the variability in faunal com!

sp[ JDM 288 position through time[ Species richness in the forest control varied throughout the study period\ with lower values being observed in the 0867Ð70 period[ # Hypoponera Pheidole Camponotus Camponotus Anisopheidole antipodum Tetramorium impressum This may in part be associated with changes in the ant

7[ 8[ fauna following a prescribed burn prior to com!

Þ 0887 British Species09[ Plot!years "codes printed vertically# mencement of the study\ as it is common for ant Continued

Ecological Society\ " Journal of Applied richness to increase shortly after a _re due to habitat Ecology\ 24\ simpli_cation and competitive release from the e}ects

050Ð071 Table 3[ of dominant ant species "Andersen + Yen 0874#\ and 067 Ant recolonization of bauxite mines

Fig[ 7[ Percentage of total ant species within each functional group for the four broad assemblage categories derived from the species dendrogram "Fig[ 6#[ The categories are] "A# ubiquitous species "assemblages 0 ¦ 3 of dendrogram#^ "B# primarily forest species "assemblages 1¦4¦5#^"C# species present in forest and older rehabilitated plots "assemblage 2#^ and "D# species con_ned to rehabilitation "assemblages 6Ð09#[

Fig[ 8[ Three dimensional ordination of the plot!years using ant presence:absence data[ Stress  9=02[ Sites are ordinated according to similarities in their species composition and a minimum spanning tree has been superimposed[ Even!thickness lines are in the plane of the paper and tapered lines represent projections backwards "thinner# or forwards "thicker# in the third!dimension[ The six groupings derived from the plot!year dendrogram "Fig[ 5# are indicated on this diagram[ Key] U  unvegetated plot^ P  planted plot^ S  seeded plot^ F  forest control plot[

to decline again when these e}ects are lessened "York forest control "during 0867#\ although it does not 0883#[ The subsequent increase in species richness in reach the mean annual species count for the three Þ 0887 British the 0873 sampling year could similarly be associated supplementary forest plots "17Ð27 species#[ On the Ecological Society\ Journal of Applied with the 0871 prescribed burn[ The outcome of these basis of these results\ it appears that species richness Ecology\ 24\ trends is that species richness in the three minesite alone is not a reliable measure for assessing ecosystem 050Ð071 plots during 0878 falls within the lower range of the recovery[ The second problem results from the natural 068 heterogeneous\ with most of the area still open and J[D[ Majer + dominated by annual weeds[ The ~oristic richness of O[G[ Nichols the planted plot is still lower than that of the area seeded with a mixture of native species although\ by the time of the _nal survey\ it had developed reason! able ground and canopy cover and strati_cation of the vegetation[ All rehabilitated plots had lower plant species richness than the forest[ These trends are largely mirrored by the ant fauna[ In the _rst paper concerning the initial 1 years of reco! lonization\ Majer "0870# concluded that the ant fauna Fig[ 09[ Calculated similarity "Sorensen|s Index# between ant showed least similarity to the forest in the unvegetated species sampled per year in the three rehabilitated minesites plot and greatest similarity to the forest in the seeded with those sampled in the same year within the forest control[ plot[ In terms of the rate of increase in species richness The horizontal line is the mean value for similarity between and also the tendency of the fauna to resemble that of the ant fauna sampled in three supplementary forest plots near Dwellingup[ Â\ unvegetated minesite^ Á\ planted the forest\ the seeding option was superior and the minesite^ ž\ seeded minesite[ planting option did little more to encourage the devel! opment of the fauna than leaving the mined area to revegetate naturally[ The current study indicates that in subsequent years\ as the richness and structure of variability of the ant fauna between pristine forest vegetation built up\ ant richness in the planted plot areas Ð no two forest plots produce the same species attained the levels of the seeded plot although\ in list[ This must therefore be taken into account when terms of ant species similarity\ it was still slightly less comparing disturbed sites with benchmark control similar than the seeded plot was to the forest[ Thus\ as sites[ Clearly\ comparison of sites in terms of their ant with the vegetation\ the ant fauna of the rehabilitated faunas should involve adequate replication of controls plots had still not completely converged on that of the and should incorporate various facets of ant faunal forest in the 03 years over which the ant monitoring composition\ including species richness\ cumulative was carried out[ Notwithstanding the comments at species richness\ functional group pro_les and faunal the beginning of this discussion\ species richness was similarity indices[ generally lower\ and species from particular functional The di}erences between the plant structural and groups\ notably climate specialists\ cryptic species and ~oristic composition of the three mined plots have specialist predators were still under!represented[ Had persisted through until the most recent vegetation we relied upon the _rst 1 years of data alone\ we would survey[ Some volunteer vegetation has established on have correctly identi_ed the superior rehabilitation the unvegetated plot[ However\ the plot is extremely procedures\ but we would have reached a more pessi!

Þ 0887 British Ecological Society\ Journal of Applied Ecology\ 24\ Fig[ 00[ Percentage of total ant species within each functional group in the forest control and in the three rehabilitated minesites 050Ð071 during the 0878 sample!year[ 079 mistic conclusion concerning the e.cacy of the plant! in 0877[ When the pits were 8 months old\ plant species Ant recolonization ing option than the one we can now make after the richness averaged 33=4 species per 79 m1 quadrat\ com! of bauxite mines accumulation of 03 years of data[ pared with 41 species recorded in a much larger 514 m1 area of the seeded plot after 08 years[ In the same pits\ Sorensen|s quotient of similarity values comparing 8! COMPARISON WITH THE CHRONOSEQUENCE month!old rehabilitation sites with unmined sites in APPROACH several cases exceeded the 9=3 recorded when our 08! The chronosequence study of Majer et al[ "0873# con! year!old seeded plot was compared to the forest con! cluded that recolonization of a rich and diverse ant trol "Table 1#[ Given that Majer et al[ "0873# have dem! fauna was assisted by rehabilitation procedures which onstrated that ant recolonization is positively cor! produced a rich and diverse plant community with related with plant species richness and diversity\ it high plant cover\ particularly within the lower strata[ would be expected that development of the ant com! The retention of logs and other woody material and munities in current rehabilitation would be more rapid the rapid production of a thick litter layer was also than in the plots studied in this paper[ Table 4 shows important\ and the whole recolonization process was the results obtained in 0881 and 0884 from the plots enhanced by the passage of time[ The results of this representing the current rehabilitation procedure[ long!term study support these earlier predictions^ the Unfortunately\ di}erent pitfall trapping procedures higher the plot scores on these habitat features\ the preclude direct comparisons with the present study more forest!like is the resulting ant fauna[ and the relatively low intensity of sampling is likely to Which is the best approach to use when monitoring miss many of the uncommon species[ It is clear that invertebrate recolonization of rehabilitated land< although the numbers of ant species vary considerably Although the chronosequence approach enabled between forest sites\ by the age of 4 years some of the adequate replication to be carried out\ it was limited rehabilitated sites are within the range recorded for by variation in site factors and changes in rehabili! unmined forest sites[ Thus\ notwithstanding the limi! tation technology in the various plots[ Thus\ the {pat! tations of this recent study\ this is an optimistic trend[ chy| nature of the chronosequence resulted in an Further evidence that current rehabilitation enables inability to describe fully the ant succession "Majer a more rapid return of fauna comes from a recent et al[ 0873#[ The advantage was that it provided rapid study of spiders in Alcoa|s bauxite mines "Simmonds\ feedback and enabled the role of site factors as deter! Majer + Nichols 0883#[ In this study\ the number of minants of ant recolonization to be fully quanti_ed\ spider species was compared in 1!year!old and 6! to although the somewhat abstract statistical parameters 7!year!old rehabilitation during 0882[ The results were were not always easy to convey to mine operation compared with similar data from the same age of personnel[ By contrast\ the long!term case study rehabilitation in 0872 and indicated that\ for a given approach provided a clear description of the ant suc! age of rehabilitation\ spider richness in 0882 was up cession which was relatively simple to describe to non! to double that which had been attained in the 0872 biologists[ The considerable time!span of the project study[ was disadvantageous and the expense involved in These _ndings emphasize the importance of seeding repeated monitoring meant that replication had to be with a rich mix of plant species in order to maximize sacri_ced[ Thus the applicability of the _ndings to the rate and extent of vegetation and associated ant other areas cannot be fully demonstrated[ The _ndings fauna return[ Although the current data concern ants\ were fully compatible with those from the short!term there is evidence that prescriptions which encourage approach\ lending credibility to those _ndings[ We the return of ants also encourage the return of other conclude that it is desirable to conduct short!term groups of invertebrates "Majer 0872^ Andersen\ Mor! chronosequence studies to provide immediate feed! rison + Belbin 0885#[ Thus\ rehabilitation which back of rehabilitation performance but also\ where enhances the ant succession may well also favour the resources permit\ to initiate long!term studies in order to verify the initial _ndings and also to provide clear evidence that a given rehabilitation procedure will encourage adequate ecosystem recovery[ Table 4[ Numbers of ant species recorded in unmined jarrah forest and minesites at Jarrahdale "J# and Huntly "H#[ The minesites had been rehabilitated using procedures which are REHABILITATION TECHNIQUES currently in use[ Rehabilitation took place in 0889 and sites were surveyed in 0881 and 0884 when pits were 1 and 4 years Since the plots studied in this paper were established old\ respectively in 0865\ rehabilitation methods have advanced con! siderably "see Ward\ Slessar + Glenister 0882#[ These Rehabilitation Unmined forest Þ 0887 British newer techniques result in a vegetation community Year J0 J1 H0 H1 J0 J1 H0 H1 Ecological Society\ Journal of Applied which increases in richness much more rapidly than 0881 3 8 3 2 03 03 02 08 Ecology\ 24\ those described in this paper[ For example\ Koch + 0884 01 8 6 7 06 6 01 00 050Ð071 Ward "0883# surveyed a number of pits rehabilitated 070 return of invertebrates which play an important role strengthening the conclusions reached from a study J[D[ Majer + in a range of ecosystem functions such as] improving of vegetation alone\ the data provide some indication O[G[ Nichols soil structure "e[g[ termites\ worms#^ nutrient cycling of the degree of re!establishment of ecosystem func! "e[g[ springtails\ mites\ millipedes#^ stimulation of tioning[ Should completion criteria become widely mycorrhizal activity "e[g[ soil microarthropods#^ adopted in the mining industry\ information such as maintenance of plant community composition "e[g[ this would prove invaluable in the development of beetles and moth larvae#^ pollination "e[g[ wasps and such criteria[ When the processes of invertebrate reco! ~ies#^ seed dispersal "e[g[ ants#^ and maintenance of lonization are su.ciently well understood\ they will the densities of other animals "e[g[ spiders\ predatory provide a valuable addition to the more widely beetles and parasitic wasps and ~ies# "Majer 0878#[ accepted physical and biological measures which are The implications of the patterns observed in the pre! currently being discussed "Tacey + Treloar 0883#[ In sent study should therefore be viewed in a broader addition\ the di}erences between the conclusions context than the ant fauna alone[ reached on the basis of 1 years of rehabilitation and Although many operators have adopted reveg! the 03 years reported on here support Fox|s "0885# etation prescriptions which produce vegetation of conclusion that more valid and in!depth _ndings can high ~oristic and structural diversity\ and are there! be reached if long!term data such as these are gath! fore likely to encourage the return of a diverse invert! ered[ The fact that substantial di}erences between ebrate fauna\ other companies still revegetate with rehabilitated and forest plots are still discernible sug! simple mixes of plants[ It follows from the present gests that even longer periods of monitoring are desir! study that such rehabilitation prescriptions will retard able if we are con_dently to answer the question {Can the development of the invertebrate fauna and\ with the original ecosystem be recreated after mining<|[ this\ the re!establishment of ecosystem functions and processes[ Several factors will determine the rate of ecological development at a site and whether it will Acknowledgements eventually converge towards that attained in sites This work was initiated with a grant from the Reserve given more advanced treatments[ Bank Rural Credits Development Fund and was con! The present study has demonstrated that the sim! tinued with the aid of funds from Alcoa of Australia pler the rehabilitation procedure used\ the longer it Ltd[ The late Fred Miller serviced the traps in the _eld will take before the ant fauna approaches that of the and John Wallace\ John Penniket and Tony Postle unmined control[ Whilst the results apply to the jarrah assisted with the sorting of ant material[ We are also forest where annual rainfall is around 0199 mm\ the grateful to Bill Freeman and John Koch for resur! results of Majer "0878# have shown that rates of ant veying the vegetation in 0884 and to Norm McKenzie recolonization in drier areas may be much slower[ for assistance with the multivariate analyses[ Alan Although data are not currently available\ it is poss! Andersen\ Barry Fox\ John Fox\ John Koch and Sam ible that the time taken for sites rehabilitated using Ward kindly commented on an earlier draft of this simpler techniques to converge towards more paper[ advanced sites and unmined controls might increase correspondingly[ Further research is needed on this topic[ Finally\ the rates at which ants recolonize References di}erent types of rehabilitation in any environment are likely to di}er from those of other fauna groups Abensperg!Traun\ M[ + Steven\ D[E[ "0884# The e}ects of pitfall trap diameter on ant species richness "Hymen! such as higher order predators "e[g[ spiders#\ litter optera] Formicidae# and species composition of the catch decomposers "e[g[ Collembola# and vertebrates[ in a semi!arid eucalypt woodland[ Australian Journal of At this stage it is not possible to determine whether Ecology\ 19\ 171Ð176[ establishing simpler rehabilitation merely delays the Andersen\ A[N[ "0889# The use of ant communities to evalu! time an ant fauna takes to reach the values recorded ate change in Australian terrestrial ecosystems] a review and a recipe[ Proceedings of the Ecological Society of Aus! in better rehabilitated sites[ For ants in the jarrah tralia\ 05\ 236Ð246[ forest\ this may be the case[ However\ in other Andersen\ A[N[ "0884# A classi_cation of Australian ant rehabilitation scenarios\ the magnitude of the delay communities\ based on functional groups\ which parallel would be determined by the type of rehabilitation\ the plant life forms in relation to stress and disturbance[ Jour! ~ora or fauna group concerned and environmental nal of Biogeography\ 11\ 04Ð18[ Andersen\ A[N[\ Morrison\ S[ + Belbin\ L[ "0885# The role factors such as the type of ecosystem\ climate and of ants in minesite restoration in the Kakadu region of Aus! natural disturbances such as _re[ tralia|s Northern Territory\ with particular reference to their use as bio!indicators[ CSIRO Division of Wildlife and Ecol! ogy Report[ CSIRO\ Canberra[ Þ 0887 British CRITERIA FOR MONITORING REHABILITATION Andersen\ A[N[ + Patel\ A[D[ "0883# Meat ants as dominant Ecological Society\ members of Australian ant communities] an experimental Journal of Applied The data provided by this study of ants have con! test of their in~uence on the foraging success and forager Ecology\ 24\ tributed to\ and augmented\ the data on plant com! abundance of other species[ Oecologia\ 87\ 04Ð13[ 050Ð071 munities in these rehabilitated areas[ As well as Andersen\ A[N[ + Yen\ A[L[ "0874# Immediate e}ects of _re 071 on ants in the semi!arid mallee region of north!western tation\ land!use and land conservation[ Environmental Ant recolonization Victoria[ Australian Journal of Ecology\ 09\ 14Ð29[ Management\ 6\ 264Ð272[ Belbin\ L[ "0879# TWOSTEP] a program incorporating Majer\ J[D[ "0874# Recolonization by ants of rehabilitated of bauxite mines asymmetric comparisons that uses two steps to produce a mineral sand mines on North Stradbroke Island\ Queens! dissimilarity matrix[ CSIRO Division of Land Use Research land\ with particular reference to seed removal[ Australian Technical Memorandum\ 79\ CSIRO\ Canberra[ Journal of Ecology\ 09\ 20Ð37[ Belbin\ L[ "0878# PATN USER|S GUIDE[ CSIRO\ Can! Majer\ J[D[ "0878# Fauna studies and land reclamation tech! berra[ nology Ð a review of the history and need for such studies[ Belbin\ L[ "0880# SSH] Semi!strong Hybrid Scaling[ Journal Animals in Primary Succession] the Role of Fauna in Reclai! of Vegetation Science\ 1\ 380Ð385[ med Lands "ed[ J[ D[ Majer#\ pp[ 4Ð22[ Cambridge Uni! Bell\ D[T[ + Koch\ J[M[ "0879# Post!_re succession in the versity Press\ Cambridge[ northern jarrah forest of Western Australia[ Australian Majer\ J[D[ "0886# The use of pitfall traps for sampling Journal of Ecology\ 4\ 8Ð03[ ants and other invertebrates Ð a critique[ Memoirs of the Erwin\ T[L[ "0880# How many species are there<] revisited[ Museum of Victoria\ 45\ 52Ð58[ Conservation Biology\ 4\ 229Ð112[ Majer\ J[D[\ Day\ J[E[\ Kabay\ E[D[ + Perriman\ W[S[ "0873# Faith\ D[P[\ Minchin\ P[R[ + Belbin\ L[ "0876# Com! Recolonization by ants in bauxite mines rehabilitated by positional dissimilarity as a robust measure of ecological a number of di}erent methods[ Journal of Applied Ecology\ distance] A theoretical model and computer simulations[ 10\ 244Ð264[ Vegetatio\ 58\ 46Ð57[ McKenzie\ N[L[\ Robinson\ A[C[ + Belbin\ L[ "0880# Biog! Fox\ B[J[ "0885# Long!term studies of small!mammal com! eographic survey of the Nullarbor district\ Australia[ Nat! munities from disturbed habitats in eastern Australia[ ure Conservation] Cost Effective Biological Surveys and Long!term Studies of Vertebrate Communities "eds M[ L[ Data Analysis "eds C[ R[ Margules + M[ P[ Austin#\ pp[ Cody + J[ A[ Smallwood#\ pp[ 356Ð490[ Academic Press\ 098Ð015[ CSIRO\ Canberra[ San Diego[ Mills\ C[\ Chandler\ R[ + Caporn\ N[ "0881# Completion Green\ J[W[ "0874# Census of the vascular plants of Western Criteria[ Proceedings of Conference on Management and Australia[ Western Australia Herbarium\ Department of Rehabilitation of Mined Lands "unpaginated#[ Curtin Uni! Agriculture\ Perth[ versity of Technology\ Perth[ Greenslade\ P[J[M[ "0862# Sampling ants with pitfall traps] Simmonds\ S[J[\ Majer\ J[D[ + Nichols\ O[G[ "0883# A com! digging!in e}ects[ Insectes Sociaux\ 19\ 232Ð242[ parative study of spider "Araneae# communities of Greenslade\ P[J[M[ "0863# Distribution of two forms of the rehabilitated bauxite mines and surrounding forest in the meat ant\ Iridomyrmex purpureus "Hymenoptera] For! south!west of Western Australia[ Restoration Ecology\ 1\ micidae# in parts of South Australia[ Australian Journal of 136Ð159[ Zoology\ 11\ 378Ð493[ Sneath\ P[H[A[ + Sokal\ R[R[ "0862# Numerical Taxonomy[ Greenslade\ P[J[M[ "0865# The meat ant Iridomyrmex pur! the Principals and Practice of Numerical Classi_cation[ pureus "Hymenoptera] Formicidae# as a dominant member W[H[ Freeman\ San Franciso[ of ant communities[ Journal of the Australian Ento! Tacey\ W[ + Treloar\ J[ "0883# What do we want completion mological Society\ 04\ 126Ð139[ criteria to achieve< Proceedings of the 08th Australian Min! Greenslade\ P[ + Majer\ J[D[ "0882# Recolonization by Col! ing Industry Council Environmental Workshop\ pp[ 135Ð lembola of rehabilitated bauxite mines in Western 145[ AMIC\ Canberra[ Australia[ Australian Journal of Ecology\ 07\ 274Ð283[ Taylor\ R[W[\ Brown\ D[R[ + Cardale\ J[C[ "0874# A zoologi! Havel\ J[J[ "0864# Site!vegetation mapping in the northern cal catalogue of Australia[ Volume 1[ Hymenoptera] For! jarrah forest[ 0[ De_nition of site!vegetation types[ Forests miciodea\ Vespoidea and Sphecoidea[ Bureau of Flora and Department of Western Australia Bulletin\ 75\ 0Ð004[ Fauna\ Canberra[ Koch\ J[M[ + Ward\ S[C[ "0883# Establishment of under! Twigg\ L[E[\ Fox\ B[J[ + Luo\ J[ "0878# The modi_ed primary storey vegetation for rehabilitation of bauxite!mined areas succession following sand mining] a validation of the use in the jarrah forest of Western Australia[ Journal of of chronosequence analysis[ Australian Journal of Ecology\ Environmental Management\ 30\ 0Ð04[ 03\ 330Ð336[ Levy\ E[B[ + Madden\ E[A[ "0822# The point method of Ward\ S[C[\ Slessar\ G[C[ + Glenister\ D[J[ "0882# Environ! pasture analysis[ New Zealand Journal of Agriculture\ 35\ mental resource management practices of Alcoa of Aus! Australasian Mining and Metallurgy 156Ð168[ tralia Limited[ "eds J[ T[ Woodstock + J[ K[ Hamilton#\ pp[ 093Ð097[ Aus! Majer\ J[D[ "0867# An improved pitfall trap for sampling ants tralasian Institute of Mining and Metallurgy\ Parkville[ and other epigaeic invertebrates[ Journal of the Australian Wilson\ E[O[ "0876# The little things that run the world "the Entomological Society\ 08\ 150Ð151[ importance and conservation of invertebrates#[ Con! Majer\ J[D[ "0879# The in~uence of ants on broadcast and servation Biology\ 0\ 233Ð235[ naturally spread seeds in rehabilitated bauxite mines[ Rec! York\ A[ "0883# The long!term e}ects of _re on forest ant lamation Review\ 2\ 2Ð8[ communities] Management implications for the con! Majer\ J[D[ "0870# The role of invertebrates in bauxite mine servation of Biodiversity[ Memoirs of the Queensland rehabilitation[ Forests Department of Western Australia Museum\ 25\ 120Ð128[ Bulletin No[ 82\ 0Ð18[ Majer\ J[D[ "0872# Ants] bio!indicators of minesite rehabili! Received 15 October 0885^ revision received 10 November 0886

Þ 0887 British Ecological Society\ Journal of Applied Ecology\ 24\ 050Ð071