Records of the Western Australian lvluseum Supplement No. 67: 337-364

Biodiversity patterns and their conservation in wetlands of the Western Australian wheatbelt

l l S.A. Halse , M.N. Lyons!, A.M. Pinder and R.J. ShieF 'Department of Conservation and Land Management, Science Division, P.O. Box 51 Wanneroo, Western Australia 6946, Australia 2Department of Environmental Biology, University of Adelaide, South Australia 5005, Australia

Abstract A total of 197 wetlands were sampled between 1997 and 2000 in a survey designed to record wetland biodiversity across the wheatbelt and south coast of Western Australia, an area of 205000 km2 Altogether, 986 wetland-associated plant, 844 aquatic invertebrate and 57 waterbird species were recorded, with an average of 73 and a range of 10-174 species per wetland. Thirty-four per cent of species were found at only one wetland. Sixteen types of wetland were recognized, based on their biological assemblages. Overall, salinity was the factor most responsible for differentiation between wetlands in terms of biodiversitv but differences between some freshwater wetland types, such as sedge sw~mps and granite rock pools, were largely attributable to other abiotic factors Among saline wetlands, the biota of naturally saline (and usually very salty) seasonal playas was distinct from that of wetlands with longer penods of inundation. It was unclear whether differences related to inundation or salinitv. Usmg cluster analysis, 22 assemblages of co-occur;ing species were identified and the distributions of 18 of them were modelled. Between 33 and 86'/'0 of the species richness of each assemblage at a wetland was explained by two to four abiotic variables. The assemblages that modelled most poorly consisted of species that were widespread and had broad ecological tolerances, with ranges extending beyond the wheatbelt, so that the survey was unlikely to have circumscribed their ecological requirements. Most assemblages consisted of a mix of plant, invertebrate and (fewer) waterbird species. Factors affecting the distribution of plants and animals within a co­ occurring assemblage often appeared to differ, especially for plants growing on the bank of a wetland. Riparian plants are probably exposed to different environmental factors, especially salinity patterns, than those influencing animals using the waterbody itself. The dramatic increase in secondary salinisation that has been observed in the wheatbelt and south coast over the past 100 years, with associated loss of freshwater habitat and changes to naturally saline playas, is likely to lead to significant loss of biodiversity. Most assemblages (and species) were associated with particular salinity ranges and there was an inverse relationship between overall community richness and salimty, especially within the waterbody. Many species typical of naturally saline playas were rarely found at secondarilv saline wetlands. Th'e predictable occurr~nce of some species assemblages, such as those characteristic of sedge swamps and saline playas of the north-eastern wheatbelt, makes it possible to identify wetlands that, if protected from secondary salinisation, will conserve large proportions of them. Some other assemblages occur at many wetlands and their conservation is assured by almost any strategy, even if they are unpredictably distributed. However, protection of rare species and assemblages that occur infrequently and somewhat randomly within the wheatbelt poses a significant challenge to wetland managers.

INTRODUCTION extreme south-west supports wet sclerophyll forest South-west Western Australia is an old, deeply and permanent wetlands while more inland areas weathered landscape with flat topography and contain open woodland or shrublands and large expanses of nutrient deficient soils (Mulcahy, episodically flooded waterbodies (Hopper, 1979; 1967; Wyrwoll, 1988). The steep rainfall gradient Beard, 1990). with distance from the coast (Figure 1) means the This paper reports results of a biological survey 338 S. A. Halse, M. N. lyons, A. M. Pinder, R. J. Shiel

Paynes Find

Kalgoorlie

ESP .~,/~~

Albany o 200 400 j Kilometres

Figure 1 Wheatbelt and south coast of south-west Western Australia showing the wetlands surveyed, rainfall isohyets, IBRA regions (Thackway and Cresswell 1995), and the Meckering line (Mulcahy 1967). 0, site on public land; e, site on private land; GSP, Geraldton Sandplain; SCP, Swan Coastal Plain; AWB, Avon Whealtbelt; ]F, ]arrah Forest; WR, Warren; ESP, Esperance Sandplain; MR, Mallee Region.

(WBS) of wetlands of the wheatbelt and south coast George et aI., 1995). The clearing of perennial native of Western Australia, with small incursions into vegetation and its replacement with annual crops adjacent forested or open woodland areas. Many and pastures caused run-off and recharge to wetlands in the surveyed area were saline. Salt has increase. As a consequence, groundwater levels been accumulating in soil profiles and have risen and salt previously stored in the soil groundwaters of the wheatbelt for hundreds of profile, as well as in groundwater, has been thousands of years (Commander et al., 1994) as the mobilised and percolated to the surface (Clarke et result of a higher rate of deposition of marine al., 2002). It has been estimated that about 6% of aerosol salt on the landscape than salt discharge via land in the surveyed area is currently salinised rivers and groundwater flow (Hingston and (groundwater within 2 m of surface) and that this Gailitis, 1976). Consequently, most playa lakes will eventually increase to 33% (Short and formed by groundwater discharge were naturally McConnell, 2001; George et al., 2002). The saline (e.g. Salama, 1994), as were some river proportion of wetlands affected is much higher systems on the south coast. Even most 'freshwater' because of their low position in the landscape wetlands had relatively high salt levels by global (Halse et al., 1993b, 2000a). standards prior to clearing of native vegetation Salinity is a major environmental gradient (Schofield et aI., 1988). However, nowadays many structuring aquatic communities (Hammer, 1986) of the saline wetlands in the surveyed area are salty and the historical prevalence of salt in wetlands of because of secondary salinisation (Mulcahy, 1978; the surveyed area has resulted in an aquatic fauna Aquatic biodiversity 339 that is relatively salt-tolerant (Williams et a/' 1991; information relevant to the three objectives is Halse et a/, 2000a; Kay et aI, 2001; Pinder et aI, reviewed below. 2002). Likewise, there has been considerable Prior to the survey, there had been little radiation of salt-tolerant plant species in, and investigation of biodiversity patterns in wetlands of adjacent to, wheatbelt wetlands (Short, 1982; the surveyed area other than for waterbirds (Jaensch Wilson, 1984; Lyons et ai, 2004). Nevertheless, et ai, 1988; Halse et a/, 1993b, 1995). Studies of secondary salinisation has the potential to wreak invertebrates were limited to a few wetlands (Halse, devastating changes on the biodiversity of the 1981; Williams et al, 1991; Doupe and Horwitz, wheatbelt because of loss of freshwater wetlands 1995; Halse et a/' 2000a) or focussed on particular and the likely changes to temporal and spatial taxonomic groups (Ceddes et al., 1981; Brock and patterns of salinity in naturally saline wetlands Shiel, 1983). The comprehensive survey of rivers by (Williams, 1999; Cramer and I-Iobbs, 2002; Halse et Kay et al. (2001) identified invertebrates only to ai, 2003). family. Studies of submerged plants were few The impact of salinisation in south-west Western (Brock and Lane, 1983; Brock and Shiel,1983) and, Australia is made more acute by the region's high other than the broadscale survey by Halse et al. conservation values. The extensive radiation of (1993a), studies of emergent and riparian vegetation vascular plant groups, especially the Myrtaceae, were restricted to particular wetlands (Froend et al., Proteaceae, Papilionaceae and Mimosaceae, has 1987; Froend and McComb, 1991; Froend and van long been recognized (Diels, 1906; Beard et a/' 2000) der Moezel, 1994). Substantially more information and the south-west was listed by Myers et al (2000) on plants and invertebrates, as well as diatoms, is as one of 25 global hotspots for biodiversity, based available as a result of the WBS (Pinder et al, 2000, on a combination of terrestrial (mainly plant) 2002, 2004, 2005; Blinn et ai, 2004; Lyons et al., species richness and the extent of land clearing. 2004). Many high-conservation value, endemic plant The general role of salinity in structuring plant species occur in high-rainfall areas (Wardell­ and animal communities within a waterbody is Johnson and Horwitz, 1996) but the number is reasonably well understood. While there is a trend greater in what Hopper (1979) termed the for community richness to be inversely related to 'intermediate rainfall zone' between 300-800 mm salinity, the affinity of different higher-level annual rainfall. This is the area covered by the WBS. taxonomic groups for saline conditions varies Hopper (1979) attributed plant richness in the study (Hammer, 1986). These patterns were confirmed in area to the existence of a mosaic of soil types and the WBS with Pinder et al. (2005) showing a tight the isolation brought about by climatic variability, negative relationship between invertebrate richness mostly since the Quaternary. and salinity at values >4 g L-l across both The importance of south-west Western Australia secondarily and naturally saline wetlands. for aquatic invertebrates is less well documented Waterbird and diatom richness also showed than for plants but it appears to be a region of negative relationships with salinity (Blinn et a!., significant richness and endemism for groups with 2004; Cale et a!', 2004). The role of salinity in drought-resistant eggs, especially crustaceans (Frey, structuring riparian plant communities, especially 1991; Maly and Bayly, 1991; Thomsen, 1999). The those of naturally saline systems, is less clear (see distribution of crustaceans has parallels with plants: Hart et al, 1991). Halse et al. (1993a) found no while many endemic species occur in areas of high relationship between plant species richness and rainfall (Storey et a/' 1993; Wardell-Johnson and natural salinity of wetlands, although secondary !-!orwitz, 1996), much of the crustacean endemism salinisation reduced richness. Lyons et al. (2004) occurs in intermediate and low rainfall zones (Halse reached similar conclusions, after comparing soil and McRae, 2001; Remigio et ai, 2001; Halse, 2002; salinity and plant richness of small quadrats in Timms, 2002). various vegetation associations around wetlands The WBS was a direct response by the during the WBS. Richness of riparian plants was Covernment of Western Australia to the threat of poorly correlated with wetland salinity probably broad-scale loss of biodiversity because of because the salt content of riparian soils reflects secondary salinisation (Anonymous, 1996b). It had microscale topography and leaching rather than the three objectives: (1) to document patterns of salinity value of wetland water (Cramer and Hobbs, biodiversity in wetlands of the wheatbelt and south 2002). coast, (2) to investigate the role of salinity and other The practice of reserving or managing areas to environmental factors in structuring communities, protect the biota within them, and thus the flora and (3) to select a set of Natural Diversity Recovery and fauna of the region, has a significant Catchments as a focus for government and international history (Margules and Pressey, 2000). community actions to ameliorate the impact of The first national park in Western Australia (John salinity on biodiversity and thus conserve Forrest) was gazetted in 1900 but it was another 52 representative wetland communities. Existing years before the first nature reserve was proclaimed 340 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

(Tammin Railway Dam). Between then and 1980, reservation (Biological Survey Committee, 1984; many wetlands within the surveyed area were McKenzie and Robinson, 1987; McKenzie et ai, reserved to provide habitat for waterfO\vl, as well 1991, 2000), with aquatic ecosystems being included as being places where ducks could be shot (Lane, in these surveys since the mid-1990s (Halse et al, 1985). Other wetlands were included in nature 2000b). reserves where the primary purpose was protection Selection of Natural Diversity Recovery of terrestrial flora and fauna. Early reservation was Catchments (BRCs) to ameliorate impact of salinity an ad hoc process but, in recent years, a number of on biodiversitv uses the same information as a relatively sophisticated mathematical methods have reserve selection process. There are currently six been developed in Australia, and elsewhere, to BRCs in south-west Western Australia (Figure 2). maximise the number of species from the regional Each BRC is a sub-catchment of 50 000 - 120 000 ha species pool that are protected by reserving a given with several or many wetlands at low points within area. The focus of these methods has been terrestrial the catchment. All contain a small number of nature ecosystems (e.g. McKenzie et ai, 1989; Nicholls, reserves, and some remnant vegetation on freehold 1989; Justus and Sarkar, 2002; Scotts and Drielsma, land, but much of each catchment is cleared 2003) but many of the principles apply to wetland agricultural land. Public money is being spent reservation. In conjunction with the development of within these catchments on salinity control, analytical methods, there has been a program of revegetation and management of uncleared land regional surveys in Western Australia to provide with the objective of maintaining existing levels of the biological data on which to base decisions about biodiversity. At the Toolibin BRC, groundwater is

Albany

Kilometres

Figure 2 Wheatbelt and south coast of south-west Western Australia showing existing Natural Diversity Recovery Catchments (hatched), major nature reserves and the Potential Recovery Wetlands selected as a result of the survey.• PRW. Aquatic biodiversity 341 being pumped from under Toolibin Lake to lower connected to active rivers and contain mosaics of the water-table and maintain health of the lake flat channels and small playas (Mulcahy. 1967; vegetation (Froend et ai, 1997; Dogramaci, 2003). It Beard. 1999). They contain water only briefly after is intended that an additional 10-20 BRCs will be large rainfall events. Lentic waterbodies include selected and that most of the species assemblages semi-permanent or seasonal basin wetlands, often identified in the WBS will be protected in these with rivers flowing into and out of them that may catchments (see Anonymous, 1996a; Keighery, connect a series of wetlands, such as L.ake Toolibin 2001). on the northern Arthur River (Froend et ai, 1997). Most basin wetlands are in the western and southern parts of the surveyed area. In higher STUDY AREA rainfall zones, the bed is usually covered by sedges The area covered by the WBS is shown in Figure while lower rainfall results in trees growing across 1. Nearly all wetlands were located between the 600 the bed unless the centre of the wetland remains and 300 mm isohvets. The area has a Mediterranean water-logged for prolonged periods (as often climate with hot dry summers and predominantly occurs), when it will be open (Halse et al. 1993a). winter rainfall, although the proportion of summer Shrubs such as Muehlenbaeckia spp. sometimes occur rain increases with distance to the north and east instead of trees in wetlands of low rainfall zones. (Gentilli, 1972). Annual evaporation varies from Other lentic wetland types include seasonally or 1320 to 2750 mm. Rainfall was relatively light, and episodically filled playa lakes. These are more wetland levels low, during 1997 and 1998 (Figure common in the eastern part of the surveyed area 3). Extensive late summer and autumn rains in 1999 and vary in size from a few 100 m 2 to several 100 2 meant that wetlands remained extensively flooded km . Many are naturally saline and support lunettes throughout that year. Rainfall patterns within the on the downwind side (Bowler, 1983) with surveyed area during 2000 were similar to 1997 and vegetation in low-lying areas around the wetland 1998, although there was extensive rain farther east. margin consisting mostly of chenopods. Playa lakes The different landforrns and vegetation are maintained as landscape features by associations of the surveyed area are reflected in groundwater discharge (Salama, 1994; Harper and the IBRA regions it covers. The boundaries of these Gilkes, 2003) but most fill only after surface or sub­ regions largely reflect geology and vegetation surface inflow. formations (Thackway and CresswelL 1995). Most A variety of vernal pools, claypans and pools on of the wetlands surveyed are in the Avon granite outcrops also occur. Vernal pools are Wheatbelt, Esperance Sandplains and Geraldton perched above regional water-tables, usually on Sandplains regions, with a small number in the impervious clay sediments, and seasonally contain Mallee and Jarrah Forest. Lake Cronin (SPS003) is shallow water for a few months. They are fed by in the Coolgardie region. In broad terms, the natural surface run-off from their immediate catchment and vegetation of the Geraldton and Esperance support dense stands of sedges and small shrubs Sandplains consists of shrublands, the Avon across the wetland. They form only in areas of Wheatbelt contains open eucalypt woodlands and moderately high rainfall and occur mostly on the the Mallee contains eucalypt mallee formations western edge of the surveyed area. Claypans are (Gibson et aI., 2004). However, surrounding plant analogous to vernal pools, occurring in low rainfall formations have relatively little influence on plant areas in the eastern part of the surveyed area. When species occurring within the regularly inundated flooded they contain either open water (often very parts of wetlands. It must also be recognized turbid) or emergent plants, such as Tecticornia approximately 90'10 of the Avon-Wheatbelt, 80% of verrucosa, Muehlellbaeckia j70nilenta and Eragrostis the Mallee, 73% of the Geraldton Sandplains and australasica. Granite rock pools have been 55'i{, of the Esperance Sandplains have been cleared comparatively well studied (Hopper et aI., 1997; of their original vegetation during the past 100 Bayly, 1999; Pinder et ai, 2000). They occur in small years (Shepherd et al. 2001), with broad-acre depressions on inselbergs and share many cropping now the main activity. similarities with vernal pools although, because of Physiognomy and patterns of inundation of their rock substrate, they usually do not support wetlands in the surveyed area are highly variable. emergent vegetation. No wetland is permanently filled, although some of The surveyed area extended to both the south and the deeper wetlands in the most south-westerly part west coasts (Figure 1) and, near the coastlines, of the surveyed area, around Lake Muir, rarely dry. saline lakes of marine origin are present. These are West of the Meckering line (Figure 1) and along the either part of old estuary systems or shallow lakes south coast, rivers have defined channels, flow in inter-dunal swales (Hodgkin and Hesp, 1998). seasonally for several months and usually dry They usually support extensive chenopd marshes during summer. Farther inland, drainage lines on their margins and sometimes stands of salt­ consist of broad palaeochannels that are rarely tolerant lvlelalellca cllticularis. 342 S. A. Halse, M. N. lyons, A. M. Pinder, R. J. Shiel

(a) (b) "''''-5P ' .::::: :-"?'" di'"...... ~ \b,lU~

(c)

IIight: si on Record

VerY much above Average Decile 10 ' Above Average Deeile 8 - <) Average Decife 4 - 7 Below Avera"e Decile ~ - 3" Very much below average Decile 1

Figure 3 Rainfall deciles in the surveyed area during 1997-2000, and rainfall over all Western Australia during 1999. (a) 1997, (b) 1998, (c) 1999, (d) 2000, (e) whole State in 1999 (data from Bureau of Meteorology). Aquatic biodiversity 343

Secondary salinisation has already affected many were most similar to those when plant data were wetlands of the surveyed area. The most visible collected. effects are increased inundation, increased salinity, A species list of vascular plants, invertebrates and and death of lake-bed and riparian vegetation waterbirds was compiled for each wetland based (Cramer and Hobbs, 2002; Halse et aI., 2003) on scoring all plant species within a variable number of 100 m 2 quadrats at the wetland (Lyons et ai, 2004), taking two 50 m invertebrate sweeps METHODS (Pinder et al., 2004), and surveying either the whole This paper is based data from 197 wetlands wetland, or a large section of it, for waterbirds. We (Figure 1, Appendix 1), which are a subset of those use the term "species" loosely to refer to the animal surveyed for plants by Lyons et al. (2004) and and plant units used in analysis. Identifications aquatic invertebrates by Pinder et al. (2004). Dams, were usually at species level but existing taxonomic reservoirs and wetlands receiving hypersaline keys enabled some invertebrate groups to be discharge water were excluded from our analysis, distinguished only at high taxonomic levels (e.g. which dealt only with naturally occurring wetlands. Nematoda). Even when keys were adequate, it was Most of these were on Crown land (nature, water or sometimes impossible to identify all animals or recreation reserves or unvested) but 65 were on plants of a genus to species level because specimens freehold land, which had usually been cleared for were immature or sterile and then it was necessary agriculture except for a narrow belt of riparian to lump identifications at genus level for analysis. vegetation, and seven were on pastoral leases. Many wetlands in reserves also had little uncleared Analysis land around them and in some cases the reserved Singleton species were excluded from the data-set area did not encompass the whole wetland (see for all multivariate analyses. Wetlands were Halse et ai, 1993a). classified into types according to the similarity of The WBS examined patterns in composition and their biota using the PATN analysis package distribution of the overall biological communities (Belbin, 1993) and presence/absence species data. in wetlands, as represented by three elements with Czekanowski's coefficient was used as a measure of different life history traits: namely waterbirds, dissimilarity and under-estimated dissimilarities aquatic invertebrates, and vascular plants within (>0.95) were re-calculated using the Shortest Path the wetland and riparian zone. We define the option. The Unweighted Pair-Group Mean Average riparian zone as extending to the high-water mark (UPGMA) fusion method, with ~=-0.1, was used to of major, regular (though not necessarily annual) group wetlands (Sneath and Sokal, 1973). The flood events. Aquatic invertebrates and waterbirds discreteness of wetland types identified by in wetlands of the central third of the study area classification was examined by ordination using were surveyed in spring 1997, the southern third Semi-Strong Hybrid Multidimensional Scaling in spring 1998 and the northern third in spring (SSH) (Bel bin, 1991). 1999 (Pinder et ai, 2004). Four additional wetlands Species were classified into assemblages of were surveyed in 2000. Wetlands of southern and species with similar patterns of occurrence using some central parts of the study area were surveyed the Two-Step coefficient of dissimilarity (Austin for plants in 1998 and those in northern and the and Belbin, 1982) and UPGMA. The degree of remaining central parts were sampled in 1999 with nestedness in each assemblage was calculated using spring and summer visits to each wetland to NESTED (Atmar and Patterson, 1993, 1995). coincide with periods of maximal flowering Nestedness was further examined by checking that activity (Lyons et al., 2004). Five wetlands were richness of each assemblage was unimodally surveyed in 2000. distributed against I-dimensional ordination scores There was temporal disparity between the of community structure, derived by SSH without animal and plant data-sets for many wetlands, masking singletons. Whether richness values of including all those sampled for fauna in 1997. each assemblage fitted a Poisson distribution was Conditions did not change much between animal checked by visual inspection after plotting them. and plant sampling if both occurred in 1997 and For each assemblage that appeared to be 1998, because these years had similar rainfall ecologically meaningful, the relationship between patterns (Figure 2), but differences were species richness of the assemblage and sometimes marked if plants were sampled in 1999 environmental attributes across the 197 wetlands and animals during the preceding two years. We was modelled using a generalised linear model have been unable to compensate for temporal (Poisson regression) in the STATISTICA analysis discrepancies except for seven wetlands in the package (StatSoft, 2001). The environmental data-set of Pinder et al (2004) that were sampled attributes available for modelling related to twice, in different years. For these, faunal data geography, climate, water physico-chemistry and were used from the year when wetland conditions two particular habitats (Table 1). Environmental 344 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

Table 1 Environmental attributes measured at, or derived for, each wetland and used in modelling. Ionic ratios calculated using milliequivalent values.

Code Attribute Code Attribute

Geographic Turb Turbidity (NTU) Lat Latitude (OS) Col Colour (TCU) Long Longitude (OE) Sil Silica (mg LI) Alt Altitude (m) Na' Sodium (% meq) Climatic Ca2' Calcium (% meq) Tann Annual average temperature (QC) M g2' Magnesium (% meq) Pann Annual average precipitation (mm) K' Potassium (% meq) Pdry Driest quarter precipitation (mm) Mn2• Manganese (% meq) Pcv Coefficient of variation precipitation Cl Chloride (% meq) Evap Annual average pan evaporation (mm) HCO, Bicarbonate (% meq) Physico-chemical SO/­ Sulphate (Ya meq) SaP Total dissolved solids (mg L-I) DMC Mgl.+ Cal': Cl 2 pI-P CS Ca ': SO/ l Alk Mg LI calcium carbonate CC Ca ': HC03+CO/- TN Dissolved persulphate nitrogen (mg L I) Habitat TP Dissolved persulphate phosphorus (mg LI) Rock Waterbody on granite outcrop 1 Chi Chlorophyll a,b,c, Phaeophytin (mg L ) Flow Flowing water when sampled

I Used as either a continuous or categorical variable

attributes were screened before constructing each became salinised was calculated to provide notional model and attributes that were not significantly indication of the adequacy of the proposed PRWs. related to richness of the assemblage were excluded The calculation assumed eventual loss of all species from the regression analysis. If several attributes outside the PRWs and BRCs, although we recognize were strongly inter-correlated, only the one with the assumption is unrealistic (see Halse et aI., 2003). most obvious biological meaning was included in analysis. A regression equation was constructed with two to four environmental attributes, using the RESULTS Best Subsets routine. Significance of the equation Altogether, 986 wetland or wetland-associated was assessed using the Wald statistic after checking plant, 844 aquatic invertebrate and 57 waterbird that outliers were not disproportionately species were recorded, with an average of 73 (range influencing coefficients. The amount of variation 10-174) species per wetland (Appendix 2). Fifteen explained was calculated by an Rl-value adjusted per cent of plant species were naturalised aliens for number of cases and environmental variables (weeds). Species occurrence was very patchy with used (Tabachnik and Fiddell, 1983). 34% of species occurring at a single wetland, 15% at In an attempt to define the habitat preferences of two wetlands and only 1.1 % at more than one-third different assemblages, their fidelity to each wetland of sites. No species was present at all wetlands and type was calculated as: five of the 10 more common 'species' were higher

F 4i = PAi • w/wi • (l/LpAi' w/w) level taxa. The more common true species were the 1-n chironomid midge Procladius paludicola (58% of wetlands), introduced herbs Hypochaeris glabra where F4i is the fidelity of assemblage A to wetland type i, p Ai is the proportion of assemblage A in (54%) and Sonchus oleraceus (43%), introduced grass Parapholis incurva (49%) and grey teal Anas wetland type i, wi is the number of wetlands in type i and w· is the average number of wetlands per type gibberifrons (48%). (see Boesch, 1977). The WBS results were used to identify some Species assemblages Potential Recovery Wetlands (PRWs) that could After deleting singleton species from the data-set, form the core of future BRCs. The PRWs represent 22 species assemblages were recognized but three the surveyed wetlands containing the largest of these appeared to be artefacts driven by the proportion(s) of the assemblages that appeared to species array at individual sites (assemblage 15 by need active protection to persist in the surveyed Lake Pleasant View SPM024, 19 by Arro Swamp area in the face of further salinisation. The SPS183, 22 by Goonaping Swamp SPS023) proportion of each assemblage that would be (Appendix 3). Information about assemblages is conserved if the PRWs and existing BRCs were summarized in Table 2. The assemblages were: protected while the remainder of the surveyed area Assemblage 1. A group of 27 species mostly ;;.­ ..0 r:; l:J

Cl Table 2 matrix of ,lS:il'rnbla\,:l'S (rows) to wetland types (columns), N represents the number of wetlands of each type or the number of times an "c;,;prnhh"p c;- member was recorded, and S represent the mean number of species per wetland and the number of species in each assemblage, respectively, Mean TOS (g L C' wetbnds of each and for occurrences of members of each assemblai!e, and mean oH at wetlands of each tvoe arc also shown. Sce text for method of calculatin" 0. re<' ....

,~'" Wetland type

VI I VIII IX II VI IV V III XI X XII XV XVI XIII XIV N 13 13 .'1 12 18 11 12 12 10 4 2.'1 11 22 12 100±Y 6Y±13 108±5 78±3 74±5 8th5 68±7 103±4 54±3 5Y±5 73±4 2~±,S 52±6 50±6 05±O2 1 ±OA 4.0±0.Y 38± ]0 43±lJ6 45±11 58±1.1 16±3 39±6 48±16 5l±8 116±27 128±21 146±35 76±OA 7 lJ±lJ 2 8.lJ±O.2 7.6±0.2 85±0.2 84±0.2 8.2±0.2 7.6±0.3 8.8±lJ.2 8.6±lJ.2 8.Y±0.2 47±lJ7 8.0±0.1 51 S N TDS

21 0006 0.102 0.000 0.036 0.007 0024 0018 0007 OODO 0000 0000 0.003 O.OOD 0.000 0000 53 16Y 20 • • 0.171 W.il;. 0.081 0.066 0.02Y OODY 0020 0050 0.005 0000 0012 0.010 0000 0002 0002 74 516 22±06 0(133 0015 O(m 0.01 4 0025 0042 0021 0.000 0.000 0.0l1 0.000 o 000 27 127 2.6±1 17 •0.054 0058 0082 0016 0.093 0.104 0.078 005Y 0.023 0010 0.012 0.003 0002 0.001 0001 8Y 854 30±OA 8 0.055 0007 0.000 0.003 0013 0028 0008 0019 0048 0000 0.000 0002 0.000 0004 (W05 84 244 3.3±1 16 0088 0183 0.025 0.021 0019 0.030 0.018 0.068 0011 0.037 0004 0.000 0008 0000 51 232 43±1 5 0.081 0.149 0.076 0,069 0.110 0.079 0.095 0.096 0.133 0036 0.044 0.009 0.0l 2 0001 0.004 0006 64 2381 4Y±03 4 -0.051 0051 0024 OOlO 0.146 0035 0006 0.000 0005 0.000 (W05 0008 0005 0007 62 191 7. ry 8 0.103 0.051 0.082 0036 .. 0.128 0.168 0.124 0.135 0.142 0.046 002] 0.002 DOI(] 0007 0008 70 88Y I 0.069 .. 2 0.027 0.088 0025 0002 0.097 0.193 0.132 0.134 0.144 0026 0.061 0013 0.023 001 0021 0005 106 577 3 0011 0007 002Y 0036 0.011 0.082 0.127 0020 0048 0.023 0.199 0000 0.006 0.036 0032 61 183 24±3 6 0.03Y 0.077 0.025 0033 0.069 0.059 0.093 0.073 0.110.. 0.067 0.156 0.059 0.056 0.025 0.033 0.027 35 2124 24t I 7* 0.119 0.142 004Y 0045 0.107 0.032 0.027 0016 0.079 0.061 0.068 0.044 0.061 0017 0.095 0.036 31 452 26±2 9 0008 0.007 0022 0.065 O.OIY 0028 0.152 0022 0.078 l1li 0.060 0.180 0017 0019 0043 0.010 30 43Y 26±2 12 0.126 0043 0.154 0004 ... 0.037 OOOY 0009 0.056 0.000 0.021 0.019 0.179 0.006 0.013 63 270 32±4 13 0.018 0.030 0010 0004 0.056 0.012 0.028 0.031 0.090 0.050 __ 0.087 0.117 0.039 68 2236 44±1 14 0.022 0004 OOlY 0.000 0.109 0.000 0003 0006 0.048 0005 0.085 0036. 0.02Y 37 802 59±2 11 0000 0.000 0.000 0.000 0.052 0.000 0000 0.010 0.023 0000 0038 0.Cll1 ..' 0.015 44 156 64±4 10 0.002 0003 0.012 0.000 0.030 ()(lOO 0007 0005 0.002 0.005 0.120 0.125 0.100 0.085 0.302 0.204 100 603 90±3

..."" (>1 346 S. A. Halse, M. N. Lyons, A. M. Finder, R. J. Shiel

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o' I . •... o

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• Assemblage 5 ....• Assemblage 6 • ',0 • • •• .••,'. o . .., . .~ f··, •.. f .... \• •tt. •• • • • ;., . • o •• ' •• . \ ... -.. ..' .. • ••# • : ••e o • .. I...... • • • . ",...... ,. ... • ~ , .. •..• • • •• • 0 0 ...... • • 0 .r. ...: ". I : 0 ••• • ,.•• '. ~."!. ,··Iliro • I _f • • •• :- 0 A I·:· ,.tl',tII6.· .. ' o 0 -:.. . ~~,,/, lit: ••o· ~.j:•

Figure 4 Distribution of species assemblages at wetlands surveyed in the wheatbelt. Assemblages 1-6. l______Aquatic biodiversity 347

associated with fresh water (mean 2.6±1.0 g LI) assemblage was best represented at Arro that represented 0.9(~, of species occurrences in Swamp (SPSI83, 14 species). the survey. The assemblage contained 11 Assemblage 8. A group of 70 species found invertebrate, 1 waterbird and 15 plant species. mostly in fresh to subsaline or weakly saline Members were absent from most wetlands and water (mean 7.2±0.7 g L I). The assemblage the assemblage tended to occur in the eastern contained 47 invertebrate, 2 waterbird and 21 central and southern wheatbelt (Figure 4). It plant species, representing 6.6% of all species was best represented at Lake Cronin (SPS003, occurrences. It was patchily distributed 15 species). throughout the wheatbelt but with a tendency Assemblage 2. A group of 106 species found mostly for greater frequency of occurrence on the in association with subsaline water (mean south coast (Figure 5). It was best represented 10.6±1.1 g Ll). The assemblage contained 54 at Boyacup Bridge swamp (SPS111, 20 invertebrate, 10 waterbird and 42 plant species species). and represented 4.3% of all species occurrences. Assemblage 9. A group of 30 halobiont species Members of the assemblage were distributed (mean 26.1±2.0 g LI) that occurred most throughout the wheatbelt, with few at anyone frequently along the south coast and south­ site (Figure 4). The assemblage was best western part of the study area (Figure 5). The represented at Murchison River (SPSI98, 29 assemblage contained 11 invertebrate, 1 species). waterbird and 18 plant species, representing Assemblage 3. A group of 61 species found mostly 3.3% of all species occurrences. It was best in or adjacent to saline rivers and wetlands of represented at Oldfield River (SPSI23, 15 the south coast (mean 23.5±1.1 g L I) (Figure 4). species). The assemblage contained 29 invertebrate, 1 Assemblage 10. A group of 100 species associated waterbird and 31 plant species and represented with saline and hypersaline water (mean 90±3 1.4% of all species occurrences. The assemblage g Ll) outside high rainfall and, usually, coastal was best represented at the Oldfield River areas (Figure 5). The assemblage was (SPSI23, 12 species). dominated by plants, containing 22 Assemblage 4. A group of 62 species in or invertebrate, 7 waterbird and 71 plant species, associated with fresh to subsaline, flowing which represented 4.9% of all species water (mean 7.1±2.5 g Ll). The assemblage occurrences. The site with most species of the contained 38 invertebrate and 24 plant species assemblage was Isthmus Lake (SPS058, 24 and represented 1.4% of all species occurrences. species). Members were concentrated at stream sites in Assemblage 11. A group of 44 species associated wandoo woodland east of Perth (Figure 4) and with hypersaline water (mean 64±4 g LI) of the the assemblage was best represented at north-eastern wheatbelt (Figure 5). The ]imperding Brook (SPS004, 20 species). assemblage comprised almost exclusively plants Assemblage 5. A group of 64 species widely with 2 invertebrate, 1 waterbird and 41 plant distributed in the wheatbelt (Figure 4) in species, which represented 1.2% of all species association with fresh to subsaline water (mean occurrences. It was best represented at Lake 4.9±0.3 g Ll). The assemblage contained 56 Moore (SPS148, 19 species). invertebrate, 1 waterbird and 7 plant species, Assemblage 12. A group of 63 species associated representing 17.7(),;, of all species occurrences, with some of the freshest and some of the most and was best represented at Range Road yate hypersaline wetlands (mean 31.8±3.6 g L I) in swamp (SPS033, 39 species). the north-eastern wheatbelt (Figure 5). The Assemblage 6. A group of 35 widespread (Figure assemblage was dominated by 47 plants species 4), salt-tolerant species (mean 23.7±0.9 g LI). which, together with 16 invertebrate species, The assemblage contained 12 invertebrate, 10 represented 2.0% of all species occurrences. waterbird and 13 plant species, representing There was considerable discrepancy between 15.8'Yo of all species occurrences, and was best plants and invertebrates in terms of the represented at Dulbinning Lake (SPS007, 25 salinities with which they were associated species). (Table 3). The assemblage was best represented Assemblage 7. A group of 31 species found over the at Yarra Yarra Lake (SPSI62, 12 species). full range of salinities (mean 26.1±2.3 g LI) Assemblage 13. A group of 68 species most (Table 2). The assemblage, which contained 10 commonly found in or near secondarily saline invertebrate, 1 waterbird and 20 plant species, wetlands (mean 44±1 g Cl). The assemblage was was patchily distributed across the whole Widespread in the wheatbelt (Figure 5) and wheatbelt and represented 3.4°!c, of all species accounted for 16.6% of all species occurrences. occurrences. Plant species were nearly all exotic It comprised 27 invertebrate, 4 waterbird and 37 weeds, without conservation value. The plant species and was best represented at Lakes 348 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

\ ,. r Assemblage 8 Assemblage 9 ~ .. Percentage ot assemblage s;;aX;;E:'s at each sile ~. Percentage of asseI';lblage sp.x'\es at \. • :5:0<30 \ . .5010<75 Getaldtotl ~\ • • 5 to<15 .3010<50 • 0 \0<5 \ • \, . \ .

r." f· :. \. •.. \ ";. Kalgoor!le \ r

Assemblage 11 Percentage of assemblage species at s

Kalgooriie ...... • .. , \ \ .' .... • ,fI' '.' • • • • • .. ., • • • • '. • •

Albany

Assemblage 12 Assemblage 13 Percentage of assemblage species at each site Percentage of assemblage species at eac!", sIte 81510<30 .30 te <50 • 510<15 815to<30 Geraldton .. 010<5 • 510<15 o Cto<$ ,.., o (16) • • • ..~. . .. · e, Ka-lgoofhe • • .. .' • • .. .. •

'. •· .

Figure 5 Distribution of species assemblages at wetlands surveyed in the wheatbelt. Assemblages 8-13, Aquatic biodiversity 349

Assemblage 16 P"'M""" '" '"e~"'..,p speCle-s at e8{:h .50 .30 ".,.. ·• to <30 (4\ .• • 1 .~.., • ,.. .. . ",. . -.-... ~. • ... , • •• • .' . .• • • • • • .. •

Albany

Assemblage 18 • of "",mblage spems

Gen31dton

~.) Kalgoor1:e • ..' .. \ ." • • •.' ,. • . ; ., • • 1 •

Albany

• Assemblage 20 Assemblage 21 Percentage of assemolage spec,t'c'S at eaCh Percentage .30 la <50 .,5· • • • • • • • • ...... • • • • • • . . • • • • ·•

Figure 6 Distribution of as'3ernblai~es at wetlands ~111r\f{"",rl in the wheatbelt. AsseJrntJla);;es 14-21. 350 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

Table 3 Mean (±SE) salinity of occurrence (g LI) of mean salinity of occurrence was 3.3±1.3 g L,I as plant, invertebrate and waterbird species in a result of a few plant records around each assemblage. SE shown only if there were hypersaline wetlands. The assemblage ~5 occurrences in a category contained 35 invertebrate and 49 plant species, Assemblage Plants Invertebrates Birds representing 1.8% of all species occurrences. It was best represented at Poorginup Swamp 21 0.9±O.7 0.4±0.1 (SPS103, 39 species). 20 3.7±1.6 1.3±0.2 Assemblage 20. A group of 74 species patchily 1 3.2±1.6 1.0±O.2 distributed though the wheatbelt (Figure 6) and 17 4.3±O.8 2.3±O.4 1.4±O.5 18 4.1±2.2 2.4±O.9 occurring predominantly in fresh water (mean 16 7.6±2.3 1.8±O.6 2.2±O.6 g L,I). The assemblage contained 41 5 12.2±2.3 4.2±O.2 6.7±2.1 invertebrate, 1 waterbird and 32 plant species, 4 14.6±6.7 2.7±0.5 representing 3.8% of all species occurrences. It 8 11.8±2.0 5.1±0.6 10.7±3.0 was best represented at Punjerwerry Claypan 2 20.3±3.1 5.6±0.5 5.6±0.7 and Weelawadji Lake (SPS197 and 177, 34 3 25.3±4.8 21.6±3.2 22.0 species). 6 32.1±1.9 20.6±1.3 15.8±1.2 Assemblage 21. A group of 53 species typical of 7 30.4±3.1 14.5±2.5 23.8±16.6 9 28.6±2.8 22.6±2.9 12.2±5.1 pools on granite outcrops (mean O.6±O.3 g L,l, 12 38.1±4.3 10.7±5.1 Figure 6). The assemblage contained 27 13 50.3±1.8 34.1±1.4 43.1±4.5 invertebrate and 26 plant species, representing 14 58.4±2.2 68.0±12.6 1.3% of all species occurrences. It was best 11 62.5±4.3 67.0 108.0±24.1 represented at Wannara Rock (SPS168, 21 10 88.7±3.9 91.9±5.7 84.9±9.8 species), Several trends were noticeable among Biddy and Coyrecup (SPS067 and SPM004, 33 assemblages. Firstly, waterbirds rarely formed a species). significant component of the species richness of an Assemblage 14. A group of 37 species typical of assemblage: even in the most bird-dominated naturally hypersaline wetlands (mean 59±2 g L-l) assemblage 6, waterbirds comprised only 29% of in the northern wheatbelt, although more taxa. Plants comprised most of the biota of naturally widely distributed (Figure 6). The assemblage saline assemblages. The ratio of plants: comprised almost exclusively plants (36 species) plants+invertebrates averaged >0.9 in the which, together with 1 waterbird species, assemblages most typical of naturally hypersaline represented 6% of all species occurrences. The sites (10, 11 and 14) compared with <0.5 in other assemblage was best represented at Weelhamby assemblages Lake and Mongers samphire pan (SPS169 and Secondly, many assemblages occurred at all SPS167, 25 species). wetland types, albeit often at very low frequency Assemblage 16. A group of 51 species occurring (Table 2). This was largely attributable to many predominantly around fresh water although plant species that grew on dunes or rises around a mean salinity was 4.3±1.1 g L-I because of wetland not closely reflecting conditions in the isolated plant occurrences around hypersaline waterbody itself and being widely distributed wetlands. The assemblage was more common across wetland types. For most assemblages, the in high rainfall areas and the south coast (Figure average wetland salinity associated with plant 6). It consisted of 30 invertebrate and 21 plant records was higher than for invertebrate records. species, representing 1.7% of all species The discrepancy increased as the assemblage occurrences and was best represented at became more halophilic, except for assemblages Youlabup Swamp (SPS124, 26 species). occurring predominantly at hypersaline wetlands Assemblage 17. A group of 89 species associated (Table 3). with fresh to subsaline water (mean 3.O±OA g L,l) Thirdly, few assemblages were tightly defined predominantly on the western margin of the spatially and the occurrence of assemblages was wheatbelt (Figure 6). The assemblage contained often patchy. For example, wetlands containing 54 invertebrate, 1 waterbird and 34 plant significant numbers of assemblage 4 species were species, representing 6.4% of all species located near Geraldton, Perth and Esperance with occurrences. It was best represented at Nalyerin only scattered, low-frequency occurrence at Lake (SPS031, 49 species). wetlands between (Figure 4). The somewhat Assemblage 18. A group of 84 species almost stochastic occurrence of assemblages was reflected completely restricted to sedge swamps, with in the relatively low number of assemblage species greatest occurrence in swamps of the south­ at individual sites. Even the site best representing western part of the study area (Figure 6). While an assemblage contained, on average, only 45% of the majority of occurrences were in fresh water, assemblage species (range 20-71%). Aquatic biodiversity 351

Table 4 EquatIOns predicting the logarithm of species richness at each site for each species assemblage and the degree of nestedness of assemblages. The adjusted R2 IS a measure of how much variation in assemblage richness is explained by each equation; rand '/0 fill are measures of noise and the frequency of occurrence of species In the assemblage, and P is the probabilitv that an assemblage is not nested (Atmar and Patterson 1995). See Table 1 for abbreviations and footnote for categories of salinity' and pH2.

Assemblage Equation for Log,S Adj R2 T % fill P

1 2.3644 - 0.0457 Pcv + 0.0405 HCO - 0.1034 0.0374 Sal' J sa, - 62 16 11 le'S 2 -124464 0.0176 Sal + 0.0024 Alk + 0.0285 Pcv + 0.0995 Long 33 8 4 4e,22 3 -11.7119 + 1.3273 flow + 0.3931 latitude - 0.0068 elevation - 53 11.3 5 2e' 0.1572 Ca:S04meq 4 -4.8503 + 1.3979 Flow + 0.0050 Pann + 0.0184 Pcv + 0.0495 Mg 47 11 6 3e J 5 7.3355 - 0.0532 Sal - 0.0362 Long 70 33 23 8e"5 6 2.6369 - 0.0040 Sal- 0.7251 pHI - 0.1397 pH2 - 108641 Mn 33 38 31 2e-" 2 8 -.0358 + 1.0679 Sail + 1.5586 Sal2 + 0.6770 Sal3 + 00367 Mg 55 22 9 3e- " 00405 CC 9 -9.6860 + 0.3569 Lat - 0.0062 Alt - 1.9000 Sail 0.0681 Sal2 + 59 22 12 Se_I;' 0.4372 Sal3 10 3.0831 - 0.0180Pcv -3.2756 Sail - 2.8694 Sal2 - 06227 Sal3 57 10 6 3e_ 3S 11 -5.3949 + 0.6050 Tann -0.0235 Pann - 10.6212 SaIl 2.8034 Sal2 - 75 16 8 2e-4 0.6572 Sal3 + 0.3606 pH 12 3.8148 + 0.0108 Alt - 0.0658 Mg - 0.0030 Sal - 0.0026 Pann 51 12 5 2e-4 13 3.6323 0.0020 Pann - 1.2524 Sail - 0.8087 Sal2 + 0.2018 Sal3 - 53 26 18 2e_ 97 0.7926 pHI - 0.2944 pH2 14 - 24369 + 0.0093 Evap - 24704 Sail - 1.4907 Sal2 00581 Mg 65 23 19 2e_ 49 16 -98974 + 04045 Lat 0.0383 Sal 0.3998 pH + 01901 K 43 13 6 5e-~ 17 7 10.2881 + 02703 Lat + 0.0038 Pann + 0.0268 Pcv 00709 Sal 76 9 8 2e- ' 18 -14.5642 + 3.9927 logPann - 0.6591 Tann + 1.3916 pH2 - 0.0005 TN 84 13 8 2e"0 20 3.7039 + 0.6485 Rock 0.0930 Sal 0.0044 Alk - 0.0254 Cl 63 3 12 8 4e_ 36 21 -2.7073 + 2.9708 Rock + 0.1348 S04 - 0.8150 CC 86 15 11 6e-9 ------, Sail < 150 mg L', Sal2 < 8000 mg L', Sal3 < 50 000 mg L', Sal4 ;:: 50 000 mg L' 2 pHI < 6.0, pH2 ;:: 6.0 drop SPS025, SPS177 R2 = 70%

Modelling assemblage occurrence aI., 1997 for a discussion of copepod distributions) Species richness values of all modelled that are stochastic with regard to the environmental assemblages were unimodally distributed across parameters measured in the WBS. ordination scores, suggesting the assemblages were The variables used in models of species richness nested (see also P-values in Table 4). Richness do not necessarily reflect the main environmental values approximated Poisson distributions for all drivers of species distributions or assemblage assemblages other than 5 and 13. Equations richness, even when R'-values are high. However, describing the distribution of species richness were salinity was an explanatory variable for 14 produced for 18 assemblages (no satisfactory model assemblages (Table 4) and for other assemblages could be constructed for assemblage 7 and no there were significant correlations between salinity attempt was made to model the artefactual and one of the variables used in the model. This assemblages 15, 19 and 22). Adjusted R'-values of strongly suggests salinity is a major driver of the equations varied from 33-86% (Table 4). community patterns. Other variables that appeared The low amount of variation (33%) explained by commonly in models were annual rainfall, pH, equations for assemblages 2 and 6 appeared to latitude, alkalinity and magnesium ion reflect biological reality rather than violation of concentration, while the presence of a granite model assumptions. Both assemblages contained outcrop was a strong predictor of the occurrence of freshwater species that were salt-tolerant and found assemblage 21 and flowing water was a predictor of throughout the wheatbelt (Figure 4) and beyond, so assemblages 3 and 4. that the WBS did not circumscribe their ecological limits efficiently. A quarter of the species belonging Types of wetland to assemblage 6 were mobile waterbirds, half the Sixteen types of wetland were recognized in the invertebrates were higher taxa (usually families or surveyed area, based on their plant and animal phyla) and many of the plants were weeds. More assemblages. The major split in the classification than half the invertebrates in assemblage 2 had poor related to the separation of primarily and secondarily dispersal ability and their occurrence may be saline sites from fresh or subsaline ones (Figure 7, determined largely by historical events (see Maly et AppendiX 4). The major wetland types were: 352 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

Type I. Minimally disturbed freshwater swamps. Type Ill. Biodiverse subsaline wetlands. Fresh to 1 Fresh water (mean 0.5±0.1 g Lt) with either subsaline water (mean 5.8±1.1 g L ). Wetlands emergent trees, shrubs or grasses on the lake­ in this group had little in common with each bed. Supported a high number of ubiquitous other. Lake Logue (SPM002) on the coast species. Mean richness was 95±8, with Arro south of Geraldton was in the final stages of Swamp (SPS183, 151 species) and Weelawadji drying and had become saline as it evapo­ Lake (SPS177, 135 species) having the most concentrated, the secondarily saline Lake species-rich communities. Assemblage 1 Dulbinning (SPS007) in the central wheatbelt occurred predominantly in this wetland type filled a month or so prior to sampling and (Table 2) and invertebrates (61% of species) was fresher than usual, Capamouro Swamp dominated the biota. (SPS163) in the northern wheatbelt usually Type II. Disturbed northern swamps. Fresh to contains hypersaline water (if water present) subsaline water (mean 4.0±0.9 g L'l). All but was subsaline when sampled because of a member wetlands were in the northern large flood event, and Peenebup Creek wheatbelt and were disturbed to some extent; (SPSl15) is a subsaline river flowing towards most contained emergent vegetation. Mean the south coast. Mean richness was 100±3, richness was 76±3, with Tardun CBC swamp with Boyacup Bridge swamp (SPS111, 113 (SPS187, 103 species) being the richest. Type II species) the richest site. Most of the wetlands were significant habitat (>20% of assemblages found at wetlands of records, adjusted for group size) for species in intermediate salinities occurred at low assemblage 12 and invertebrates (55% of frequency in type III wetlands; invertebrates species) dominated the biota. formed a greater percentage of the biota (52% of species) than plants (39%). Type IV. Semi-permanent subsaline wetlands. Fresh Type I, undisturbed freshwater to subsaline water (mean 4.3±0.6 g Ll). Mostly swamps (9) on south coast, usually with extensive fringing trees. Mean richness was 84±5, which was Type 11, disturbed northern almost 20% lower than type Ill. The swamps (18) assemblages occurring in the two wetland types Type Ill, biodiverse subsaline wetlands (10) were similar, with type IV wetlands Type IV, semi-permanent differentiated largely by a greater proportion of subsaline wetlands (12) I species in assemblages 3 and 9. Invertebrates dominated the biota (57% of species) but more Type V, disturbed subsaline wetlands (12) I waterbird species were present (13%) than at Type VI, westward flowing any other wetland type except X. The richest rivers (11) site was Meeking Lake (SPS038, 102 species). Type VII, granite rock and Type V. Disturbed subsaline wetlands. Fresh to vernal pools (13) subsaline water (mean 3.6±0.7 g L·l, excluding Type VIII, daypans and I SPS199 where sampling included areas much shallow yate swamps(5) fresher than the recorded salinity). Occurred Type IX, sedge swamps (12) I throughout the wheatbelt, other than the south coast. Mean richness was 67±6, which was more than 30% lower than type III and the number of Type X, secondarily saline assemblages making use of the wetlands was wetlands (25) fewer than for III and IV (Table 2). Invertebrates Type XI, saline sou1h coast rivers (4) were very much the dominant element of the Type XII, coastal saline lakes I biota (71% of species) with the lower species (11) richness in type V wetlands largely the Type XIII, alkaline hypersaline consequence of a depauperate flora. The richest lakes (12) site was Qualeup Lake (SPS032, 126 species), Type XIV, species-rich acidic hypersaline playas (9) which had almost twice as many species as any other wetland in the group. Type VI. Westward flowing rivers. Fresh to Type XV, saline playas (22) subsaline water (mean 3.8±1.0 g L·l). Mean Type XVI, species-poor acidic richness was 70±4, with Skelton Gully (SPS193, hypersaline playas (8) I 97 species) being the most species-rich site. Half Figure 7 UPGMA classification of wetlands into types the records of assemblage 4 occurred in this based on their biota. Number of wetlands in wetland type and several other assemblages of each type shown. intermediate salinities also occurred at Aquatic biodiversity 353

moderate frequency; invertebrates dominated (47.9±165 g Ll). l'he two subsaline wetlands in the biota (70(>;) of species), this group (SPS121, SPS122) were saline but Type VII. eremite rock pools and vernal pools, freshened after rain shortly before sampling With their very small, mostly hard rock, (Pinder et ai, 2004a). The wetlands were located catchments these sites were the least saline of on the coastal plain of the south and west coasts any wetland type (mean OA±0,2 g LI), There and had mean richness 56±4, with Mullet Lake were two obvious sub-groups: pools on granite (SPSI41, 82 species) the richest site, outcrops and three shallow, clay-based vernal Assemblages 3 and 9 occurred in type XII pools plus a shallow creek high in the wetIands in significant proportions; just over landscape, Mean richness was 82±5, with half the biota (53%) comprised plant species. Wanarra Rock (SPS176, 117 species) being the Type XIII. Alkaline hypersaline playas. Hypersaline most species-rich site, Type VII wetlands were (128±21 g LI), alkaline (8.0±0.1) water. Primarily the dominant habitat for assemblage 21, with hypersaline playa lakes, mean richness 50±6, assemblages 20 and 16 also occurring in with Anderson Lake (SPS106, 94 species) being significant proportions, Slightly more the richest site. Assemblage 10 occurred in invertebrate species (55'1'0) were present than significant proportions and other assemblages plants (45°1<»), associated with high salinities were present in Type VIII. Claypans and shallow yate swamps, Two low frequencies. Plants dominated the biota groups of wetlands occurred within this type: (76% of species). turbid claypans and clear-water shallow yate Type XIV. Species-rich acidic hypersaline playas. swamps, Both were fresh (mean 05±0,2 g LI). Hypersaline (146±35 g L'!), acidic water (4.6±0.6, Mean richness was 62±12, with Punjerwerry excluding the alkaline Kondinin samphire Claypan (SPS197, 100 species) being the richest marsh SPS017 which had a salinity of 10 g LI site. Assemblages 20, 1 and 16 occurred in and pH of 9.2). Primarily hypersaline playa significant proportions; the biota was lakes, mean richness 49±6, with Crook's wetland dominated by invertebrates (70'1<) of species), (SPS076, 58 species) being the richest acidic site. Type IX. Sedge swamps. Fresh water (1 ,1±OA g L,I), Assemblage 10 occurred in significant Mean richness was 98±5, with Nalyerin Lake proportions and other assemblages associated (SPS031, 130 species) being the richest site, with hypersaline conditions were present in low These wetlands provided the main habitat for frequencies. Plants dominated the biota (80% of assemblage 18, and significant habitat for species). assemblages 17, 16 and 4, The biota was Type XV. Saline playas. Saline water (51±8 g L I). dominated by invertebrates (63% of species), Primarily saline and alkaline, mean richness Type X. Secondarily saline wetlands. Almost all 71±3, with Mongers samphire pan (SPS167, 114 these wetlands contained fresh or subsaline species) being the richest site. Assemblages 11 water prior to land clearing but are now more and 14 occurred in significant proportions and saline (Bennetts Lake spson may be a naturally most other assemblages typical of saline saline exception), Mean salinity was 38.7±65 g conditions were present. Plants dominated the LI and mean richness 54±3, with Stennetts Lake biota (66% of species). (SPS075, 71 species) the richest site. The Type XVI. Species-poor acidic hypersaline playas. wetlands provided significant habitat for Hypersaline (116±26 g LI), acidic water assemblage 13 and most assemblages typical of (4.7±0.71, including two sites with pH -8). saline water were present at low frequencies. Disturbed primarily hypersaline playa lakes, ,Half the species were plants, with waterbirds usually with increased inundation as a result of comprised 13(;<) of the community to make type secondary salinisation, these wetlands were X (together with IV) the wetland type depauperate with mean richness 21±4. Wetlands supporting most waterbird species. with most species were Masters saline lake Type XL Saline south coast rivers. Three south coast SPS097 and Kondinin salt marsh lake (43 and 34 rivers and an adjacent swamp that appeared to species, respectively) but neither was typical of cluster with rivers on the basis of plant the type. Only assemblage 10 had more than 5(/0 composition, Saline water (16.0±6.5 g LI) and of its occurrences in this wetland type. Plants mean richness 68±6, with Oldfield River dominated the biota (67% of species). (SPSI23, 68 species) the richest of the river sites. The different wetland groups were comparatively The sites appeared to be important habitat for well separated in ordination space (Figure 8), species of assemblages 3 and 9, although small providing evidence that the wetland types group size means this conclusion should be identified in Figure 7 represented distinct treated cautiously, Invertebrates comprised the communities. Sedge swamps and granite rock pools largest proportion of the biota (58% of species). (types IX and VII) were the wetland types in fresh Type XII. Coastal saline lakes. Saline water water with most clearly distinguished communities. 354 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

The ordination of freshwater wetlands supported a division within type VII between the vernal pools (a) (Goonaping SPS023, Youlabup SPS124 and Ngopitchup SPS102) and granite rock pools, although we did not recognize this in the wetland classification. Claypans and shallow yate swamps (type VIII) formed a heterogeneous group with 20

Punjerwerry Claypan (SPS197) and Frank Hahn , 5 o Fresh National Park claypan (SPS087) having different • Saline communities from each other and other type VIII 10 wetlands. Among the saline wetland types, there 05 10 was considerable heterogeneity within species-poor 00 05 acidic hypersaline playas (type XVI), which resulted 00 in some overlap with other hypersaline wetlands '()5 o .()5 (types XIII-XV) (Figure 8). Species-rich acidic ., 0 • hypersaline playas and saline playas (types XIV and -1.0

XV) also showed some overlap with each other. 20 '5 10 05 00 .() 5 ·'0 ., 5 .20 .25 Jurien coastal lake (SPS178) and Hutt Lagoon (SPS189), the only northern wetlands among type XII (predominantly southern coastal saline lakes), (b) were outliers but grouped together.

Singleton species o 0 o <>1 More than one-third of species were recorded at t:. 11 1S o III only one wetland and were excluded from o IV multivariate analyses for mathematical reasons 10 •VA VI (Belbin, 1993). Plants comprised 55% of all • VII O.S • VIII singletons, invertebrates 43% and waterbirds 2%. o IX Within the three elements the percentage singletons 00 was similar for plants and invertebrates (36% and -os 33%, Figure 9a,b) but lower for waterbirds (19%). 10 os Individual wetlands contributed disproportionately 1 S to the list of singletons, with 6% of sites accounting 00 1.0 • for one-quarter of all singletons. Most of these sites os -os were either on the wetter, western side of the 00 ·10 wheatbelt or in the north (Figure 10) and it is likely that many of the singletons in these wetlands were species with core ranges outside the wheatbelt, (c) either in the south-west forest or the northern arid zone.

The number of singleton species was significantly 10 correlated with overall species richness at each site (r = 0.43) and negatively correlated with salinity (r = O.S •X • XI -0.23) but the relationships had little explanatory o XII 00 power. Most wetland types had few singletons, o XIII t:. XIV with sedge swamps (type IX) the most obvious <>xv AXVl exception (Figure 9c). Individual sites with large numbers of singletons occurred in type I (Arro Swamp SPS183, 23 species), type VI (Murchison River SPS198, 13 species), type VII (Goonaping -os Swamp SPS023, 24 species) and type IX (Poorginup 10 ·10 os Swamp SPS103, 22 species). Hypersaline wetlands -1.S 00 supported relatively few singletons (Figure 9c), ·2.0 -1.0 with the greatest number occurring in Kondinin salt marsh lake (SPS016, 7 species). However, the proportion of the flora at individual hypersaline Figure 8 Ordination of wetland groups in the wetlands that were singletons was much higher wheatbelt as defined by UPGMA clustering. than for the invertebrate fauna (Figure 9d). (a) all groups, (b) freshwater groups I-IX, (c) Beaumont Nature Reserve (SPS130, 4 species) stood saline groups X-XVI. Stress = 0.19. Aquatic biodiversity 355 out for its invertebrate singletons. Secondarily particular, knowledge of the naturally saline saline wetlands (type X) and disturbed subsaline systems within inland palaeo-channels has been wetlands (type V) supported few singleton species. greatly improved. Eight new species were discovered, as well as numerous populations of species previously found in few localities and DISCUSSION considered restricted (Lyons et aI., 2004). One of the Waterbird distributions in the wheatbelt and major outcomes of the WBS has been showing that south coast, and the factors controlling them, were wetland communities of the wheatbelt and south well understood prior to the WBS as a result of coast are substantially richer and more complex surveys in the early 1980s (Jaensch et aI., 1988; Halse than previously recognized. In addition, the et aI., 1993b) but the WBS considerably improved surveyed area has a moderately rich diatom fauna knowledge of invertebrates and vascular plants. For (Blinn et aI., 2004). Protection of these biological example, it was estimated by Anonymous (1996a) communities should be a conservation priority. that there were only 200 aquatic invertebrate In terms of localised biodiversity patterns, nearly species in the wheatbelt compared with nearly 1000 all wetlands in the Wheatbelt are significant. now known from the WBS and related monitoring Average instantaneous numbers of plant, programs (Cale et ai, 2004; Pinder et ai, 2004). invertebrate and waterbird species associated with While the vascular flora was better known than wetlands in types I (freshwater), III (biodiverse aquatic invertebrates, the WBS represented the first subsaline) and IX (sedge) were 2:: 100. Only type systematic floristic survey of wheatbelt wetlands. In XVI wetlands (species-poor acidic hypersaline)

(d) 14

';;:: 12 .. 10 ~ <:> 8 <: 6 "6ll ,~ 4 '0 2 "I- O-+--...... ,...... ~...... ,...-L....L.,,...... ,.-...,...... >.... > 3 ­ > Wetland type Figure 9 Frequency of occurrence of singletons in wetlands. (a) invertebrates, (b) plants, (c) percentage of all plant or invertebrate singletons in each wetland type, (d) average percentage singletons in the plant or invertebrate species list at wetlands of each type. Invertebrates, solid bars; plants open bars. 356 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

\ were depauperate (average of 23 species). However, , 1nvertebrates ':- . Of !;mqlf>IOlY& at each some wetland types (e.g. X secondarily saline) were \~ . dominated by widespread species and their \. irreplaceability at a regional scale is low (see Geraldtor. '\, Pressey et al., 1994). Protection of individual • wetlands containing widespread species is usually ., not critical to maintaining the regional species pool but may be very important for maintenance of the '. KargoOfl!€ overall populations of some waterbird species \ (Halse et al., 1995 and references therein). : The most commonly occurring assemblages were .•... 5 (widespread, fresh to subsaline), 8 (fresh to weakly saline, mostly south coast) and 13 • " (secondarily saline), which accounted for about half f , ~,--I . .' the species records (Table 2). The abundance of two \~~ ·• salt-tolerant freshwater assemblages reflects the .,. • ·j'cO~--i). greater richness of the freshwater biota, compared \"~~ ~1 "'-'-"~--'~-,"'~~ with that of highly saline systems, and the Albar:y importance of salt tolerance if species are to occur commonly. It should be emphasized, however, that \ Plants Number of slr'lg'etons at each site the relative frequency of different assemblages, as r .>~O .>5 perceived by survey analysis, was partly a reflection \. of sampling design. An attempt was made to (""",Idlon .\\ , sample the full range of natural wetland types in the surveyed area (see Lyons et al., 2004; Pinder et 1 •. • ~ '01 '. al., 2004) but not necessarily in proportion to their \. .~ .. abundance. For example, assemblage 21 (granite \ specialists) comprised 1% of species records. The \ assemblage was more-or-less restricted to granite \ .... •• outcrop pools, which represented 5% of the Perth~' 1 ••.. wetlands sampled. Its frequency of occurrence ~ • would have increased if more granite pools had been sampled.

Biodiversity patterns and surrogate taxa Many approaches to reservation, based on mapping plant associations or environmental surrogates of biodiversity, implicitly assume that the different taxonomic elements of biological communities respond in the same way to the same environmental parameters and, thus, are similarly distributed (see Margules and Pressey, 2000). Recent work, including the WBS, has shown this is not true at the scale of a wetland or terrestrial site (McKenzie et al., 2000; Davis et al., 2001; Fleishman et al., 2002). In part, this is the result of various organisms being distributed at different scales. Most manageable conservation units (such as a wetland and associated vegetation) are composed of mosaics of microhabitats, with the distribution of the biota being controlled within these microhabitats. For example, the relationship between wetland salinity and invertebrates is different from that between wetland salinity and plants, even for members of the same assemblage (Table 3), because most plants grow on the bank rather than in the water column. Wetland salinity Figure 10 Distribution of singleton species at wetlands values are often poorly correlated with soil salinity surveyed in the wheatbelt. on the bank and, in fact, there is considerable Aquatic biodiversity 357 variation in soil salinity on the b,mk allording to plants found in fresh water at the end of summer, small-slale topographiGll variation (Lvons t't ai, some late-flowering herbs around claypans and 2(04). The ability of waterbirds to move between RlIppia spp. (identification difficulties) were under­ wetlands means their distribution may not be fully represented in the dataset. We undertook further determined by the charalteristils of the wetland at analysis of some of Cale et al.'s (2004) waterbird which they were recorded. Thev mav feed at a and wetland data to show that, although waterbirds productive saline microhabitat, flv to a freshwater are highly mobile, instantaneous composition of seep in another wetland to drink and roost in waterbird communities can be characterised well suitable microhabitat of a third wetland (Norman, enough by single surveys during spring, such as 1983; see also Roshier et al., 2(01). used in the WBS, to distinguish broad categories of The varied responses of different taxa to their wetland (Figure 11; see also Halse et aI., 2000a). environment means that it is rare for one group of Large temporal fluctuations in wetland depth and organisms to be an effilient surrogate for the salinity (both increases and decreases) sometimes Olcurrence of others at a site and, ideallv, reserve cause substantial shifts in wetland communities. For selection should be based on survevs of all the biota example, the waterbird community at Lake Logue (see Gaston, 2(00). This was prevented bv logistical (SPM002) showed substantial differences between constraints in the WBS, as is always likely to Ollur the dry year of 1997 when the lake was 0.36 m deep in broad-scale surveys. Nevertheless, the necessity in spring and the wet years of 1999 and 2000 when of procedures for reserve (or in this case BRC) it was ca 3 m (Figure 11, Table 6). On the other selection being explicitly based on a range of taxa hand, Halse et al (2000b) found the relationship was recognized and we surveyed aquatic between sites based on invertebrate samples invertebrates, waterbirds and plants. These remained constant across annual rainfall events in elements operate at different spatial sca have the southern Carnarvon Basin, and invertebrate and different life histories and represent both the waterbird data collected in south-west Western waterbody and its surroundings. In terms of Australia according to WBS protocols have shown a conservation and public interest, the riparian zone consistent relationship between wetlands across (or immediate surroundings of a vvetland) is as years when wetland conditions have been similar important a habitat as the waterbodv itself. The (Cale et aI., 2004; Figure 11). Similar results are protection of terrestrial fauna species, including likely for plants, with extreme flooding and very frogs, using the riparian zone was addressed in the low water levels affecting communities WBS by McKenzie et al. (2004). substantially, but the communities remaining stable at intermediate water depths, except for minor Reliability of survey patterns rainfall-induced variation in the species One of the most significant issues with respect to composition of annual plants. Even annuals have the WBS is how well single surveys characterised adaptations to recruit at varying elevations wetlands and, therefore, whether the wetland types depending on water depth in a given season, so and species assemblages identified in this paper that overall plant composition is relatively really reflect patterns of the wheatbelt and south independent of the degree of flooding. The WBS coast. Reliability issues fall into two classes: (1) how plant sampling was designed to capture all zones of well sampling reflected instantaneous community recruitment and minimise the effect of year on patterns, and (2) whether temporal variation in survey results (Lyons et al., 2(04). climate is likely to have affected patterns obtained. Given that the northern wetlands were flooded We use the term 'instantaneous' principally to refer beyond their usual boundaries and were less saline to community composition during the season of than usual when sampled in 1999, while wetlands sampling, although our testing of the invertebrate surveyed in 1997 and 1998 in central and southern protocol also examined how well community areas were experiencing dry, saline conditions (see composition at the actual time of sampling was Figure 2), it is possible that some long-term documented. relationships between wetlands of the wheatbelt Halse et al (2002) examined the adequaly of and south coast were obscured by rainfall patterns invertebrate WBS sampling and analytical during the WBS by the kind of responses observed techniques to document patterns of instantaneous at Lake Logue (Figure 11). Extensive rainfall invertebrate communities. Thev were able to throughout the northern parts of Western Australia discriminate between communities of five basin in 1999, at the same time as the northern wheatbelt wetlands along a salinity gradient. Given the static was flooded, also allowed some tropical nature of vaslular plants and the considerable invertebrates to extend their ranges southwards to survey effort used, it is likely that instantaneous the wheatbelt (see Pinder et ai, 2004a). Some community patterns of plants were also sufficiently waterbird species (e.g. Hima/ltoplls hima/ltopus) well documented to characterise a wetland (Lyons made the reciprocal movements and more-or-less et ai, 2(04), although some species of submerged disappeared from the wheatbelt (S.A, Halse and 358 S. A. Halse, M. N. Lyons, A. M. Finder, R. J. Shiel

0.5 * * <>* 0 + Bryde wet 0.0 OA •• + ... • <> Bryde ++ <> Bryde dry Logue wet -0.5 •0 Logue dry A. + Towerinning A Coyrecup OA A Coyrecup dry -1.0 Wheatfield *0 Noobijup Bennett's wet •0 Bennett's dry Coomelberrup dry

Figure 11 Ordination of waterbird communities at a series of wetlands surveyed in spring of different years (see Cale et al. 2004 for survey methods and Table 6 for information on wetland depths and salinities). Stress = 0.18.

G.B. Pearson unpublished data). Nevertheless, In the WBS, species assemblages were adopted as conditions at most northern wetlands in 1999 were the units on which conservation measures would be probably not extreme enough to have had major based but a combination of modelling, fidelity impact on community characterisation and we analysis of species assemblages to wetland types, suggest most of the WBS patterns are reliable. proportion of assemblages at species-rich sites and assemblage mapping have been used to form the Potential Recovery Wetlands basis for recommendations about conservation of One of the major objectives of the WBS was to assemblages and the wheatbelt biota. Summaries for identify wetlands that might form parts of BRCs. each assemblage in terms of types of wetlands and The approach we adopted to identify PRWs is areas where the assemblage is best represented, similar to that used by McKenzie et al. (1989, 2000) need for conservation, and the proportion of the to identify conservation reserve requirements of whole assemblage likely to occur at anyone site, terrestrial systems in the Nullarbor and southern are presented in Table 5. Where there is a need for Carnarvon Basin regions of Western Australia. They conservation, we have suggested 1-3 surveyed modelled the occurrence of each assemblage in the wetlands or complexes that might be protected to region of interest to provide the basis for selecting conserve the assemblage. These PRWs should be conservation areas in parts of the region that had regarded as indicative of the kinds of wetlands in not been surveyed. However, wetland assemblages need of protection; in many cases further survey are often poorly predicted by models (see Table 4) may reveal wetlands supporting a higher and only amenable to mapping as species richness proportion of the relevant assemblage. The notional isoclines when the assemblage is almost ubiquitous percentage of each assemblage that would (see Figures LH'». McKenzie et al. (2000) attempted conserved by protecting the 19 PRWs, in addition to overcome these difficulties by basing to existing BRCs, in an otherwise salinised conservation recommendations in the southern landscape varied between 42 and 100% (Table 5). Carnarvon Basin on a wetland classification rather This represents 72% of the waterbirds recorded than on assemblages. during the WBS, 59% of the aquatic invertebrates ------Aquatic biodiversity 359

Table 5 Suggested focus for conservation of the various wheatbelt and south coast species assemblages. Preferred wetland types, part of the surveyed area where assemblage most common, sensitivity to salinisation, potential recovery wetlands (PRWs) and the maximum proportion of the assemblage present at individual wetlands are listed. The proportion of each assemblage that would be conserved (PC) by protecting the PWRs and existing Natural Diversity Recoverv Catchments from salinisation is also shown.

Assemblage Comments PC

Type I and VIII wetlands, mostly ll1. south-eastern wheatbelt and south coast with restricted 0.67 occurrence, sensitive to salinisation, extends beyond wheatbelt, PRW Lake Cronin, proportion of assemblage at individual sites >0.5 2 Types I, II, III, IV, V, VI wetlands and rivers, Widespread occurrence, some tolerance of 0.42 salinisation, no special conservation requirement, proportion of assemblage at individual sites <0.3 3 Types IV, XI and XII rivers and wetlands, mostly on south coast with restricted occurrence, 0.44 some tolerance of salinlsation, PRW Lake Warden BRC, Oldfield River, proportion of assemblage at individual sites <0.3 4 Type VI rivers, mostly in wandoo woodland east of Perth, sensitive to salinisation, PRW 0.47 Jimperding Brook, proportion of assemblage at individual sites <0.3 5 All fresh or sub-saline wetland and river types, Widespread occurrence, sensitive to 0.97 salinisation, no special habitat requirement, proportion of assemblage at individual sites >0.5 6 All wetland types except some very fresh and some hypersaline ones, widespread occurrence, 1.0 tolerant of salinisation, no special habitat requirement, proportion of assemblage at individual sites >0.5 7 A plant-dominated assemblage, most of which arc weeds, no special habitat requirement 0.87 8 Most fresh or sub-saline wetland and rIver types, mostly on south coast and higher rainfall 0.81 parts of wheatbelt, sensitive to salinisation, no special habitat requirement, proportion of assemblage at individual sites <0.3 9 Types IV, XI and XII rivers and wetlands, mostly on south coast, moderately restricted 0.97 occurrence, some tolerance of salinisation, PRW Lake Warden BRC, Oldfield River, proportion of assemblage at individual sites 0.3-D.5 10 Types XIII and XIV wetlands, mostly in eastern wheatbelt, some tolerance of salinisation, PRW 0.64 Isthmus Lake, Lake Altham, Kondinin Samphire Marsh, proportion of assemblage at individual sites <0.3 11 Type XV wetlands, in north-eastern wheatbelt, sensitive to salinisation, PRW Lake Moore, 0.80 Weelhamby Lake, proportion of assemblage at individual sites 0.3-D.5 12 Stronger affinity to northern and eastern wheatbelt than to wetland type, probably sensitive 0.48 to salinisation, no special conservation requirement other than wetland in north-eastern wheatbelt (PRW Wannara Claypan), proportion of assemblage at individual sites <0.3 13 Type X and other saline/hypersaline wetlands, Widespread occurrence, tolerant of salinisation, 0.91 no special habitat requirement, proportion of assemblage at individual sites 0.3-D.5 14 Type XV wetlands, mostly in north-eastern wheatbelt, sensitive to salinisation, PRW 0.97 Buntine-Marchagee BRC, Weelhamby Lake, proportion of assemblage at individual sites >0.5 16 Types VII and IX wetlands, mostly south-east of wheatbelt, sensitive to salinisation, PRW 0.73 Youlabup Swamp, Ngopitchup Swamp), proportion of assemblage at individual sites <0.3 17 Type IX wetlands, western edge of wheatbelt, sensitive to salinisation, PRW Nalyerin Lake, 0.93 Lake Muir BRC, proportion of assemblage at individual sites <0.3 18 Type IX wetlands, south-western edge of wheatbelt, sensitive to salinisation, PRW Lake 0.95 Muir BRC, Nalyerin Lake, proportion of assemblage at individual sites 0.3-D.5 20 Types VII and VIII wetlands, patchy occurrence throughout wheatbelt, sensitive to salinisation, 0.82 PRW Punjerwerry Claypan, proportion of assemblage at individual sites 0.3-D.5 21 Type VII wetlands, granite rock outcrops in eastern wheatbelt, protected from salinisation, PRW 0.66 Wannara Rock, Dunn Rock, proportion of assemblage at individual sites 0.3-D.5 and 55% of the plants based on single surveys. afforded by PRWs demonstrate that levels of When additional data from some PRWs and BRCS protection estimated in Table 5 need qualification. that had been sampled on multiple occasions were Firstly, on the positive side, some assemblages are included in the analysis, 93% of waterbirds were unlikely to be threatened by salinisation. This is sometimes found in the protected wetlands (see most obviously true for assemblages 6 and 21. The Call.' et aI., 2004). former consists of Widespread salt-tolerant species The above two estimates of waterbird protection that occur everywhere, including salinised 360 S. A. Halse, M. N. Lyons, A. M. Pinder, R. J. Shiel

Table 6 October depth Zind sallnltv (electrical wetland, PRWs may help achieve conservi1tion of conductivitv) 111 different vears at eight more pli1nt i1nd invertebri1te species than the wetlands in the Wheatbelt where waterbird ani1lyses herein suggest. communities were monitored (Call' ct al. 2004). A third, somewhat negative, consideration is the Year Depth Salinity achievability of complete protection in recovery (m) (mS cm'!) catchments. Some PRWs are likely to become degraded despite attempts to control salinity Lake Bryde 1997 1.74 2540 (Clarke et ai, 2002) and assemblage members 1999 0.05 53700 relying on these wetlands may be lost (Haise et ai, 2001 0.48 9510 Bennett's Lake 1998 0.6 1865 2003). However, the figures presented here on 2000 2.43 3810 future protection of the biota relate only to the 2001 2.95 2770 surveyed area and many species deemed to be at Lake Coomelberrup 1998 03 32800 risk i1lso occur in regions without a salinity threat. 2000 N/A 91300 For example, the blue-billed duck OXYllra allstralis 2002 0.05 160900 occurs on the Swan Coastal Plain (as well as in Lake Coyrecup 1997 0.9 56100 eastern Australia), the copepod Calamoecia attCll11ata 1999 1.09 56800 and mayfly Tasmallocoellis tilyardi are widespread 2001 0.35 125000 Lake Logue 1997 0.36 12040 through southern Western Australia, the sedge 1999 3.65 1929 Baumea articulata is widespread in coastal 2000 2.52 3390 freshwater wetlands across southern Australia, and 2002 0.28 35700 the chenopod Tecticornia verrucosa grows wherever Noobijup Swamp 1998 0.7 3800 suitable habitat occurs throughout Western 2000 N/A 3810 Australia. Loss of these species from the wheatbelt 2002 0.8 5700 will not cause extinction. Lake Towerinning 1997 3.19 9060 1999 3.34 9300 2001 2.37 16880 Rare species Lake Wheatfield 1997 2.0 10900 Our analysis of the level of protection afforded to 1999 2.5 9010 the aquatic biota by PRWs ignores singleton species, 2001 1.92 9080 which comprised 34% of the biota. While some singletons have considerable conservation significance, many are not localised, rare species. wetlands, and it was the only assemblage fully The occurrence of many singletons on the edge of protected by the suggested 19 PRWs. Assemblage the surveyed area (Figure 10) suggests their 21 is the least salt-tolerant assemblage but occurs in apparent rarity is a sampling artefact. The steep a habitat (granite rock outcrops) that will not rainfall gradients to the west and south of the study become salinised (Pinder et ai, 2000). area cause considerable turnover in the biota over Secondly, BRCs will nearly always contain a short distances (Hopper, 1979), which can be greater array of wetlands than we have sampled expected to lead to frequent occurrence of and, consequently, will support a greater singletons in surveys. The invertebrate singletons in proportion of some assemblages than the PRWs the northern wheatbelt were mostly tropical species with which they are associated. For example, the that had extended south in a wet year (Pinder et al., Lake Muir BRC contains ca 100 wetlands, of which 2004). we sampled three. Twenty-seven Muir wetlands Even within the main body of the study area, were sampled two or three times each in 1996-97 where the highest proportion of singletons and yielded 488 invertebrate species (A.W. Storey, requiring special conservation focus would be R.J. Shiel and S.A. Halse unpublished data) expected to occur, most singeletons do not warrant compared with 228 from the WBS sampling. protection. Many plant singletons were species that Similarly, the Lake Bryde and Buntine-Marchagee occurred commonly at higher elevations in Recovery Catchments support some freshwater terrestrial habitats around wetlands. Only 5% were wetlands we did not sample, as well as a large Priority Taxa (see Coates and Atkins, 2001) that, number of small salt pans in braided palaeo­ along with the single Specially Protected waterbird channels, and are likely to support more species (Botaurlls poiciloptilllS), will require special than WBS data suggest. In addition to extra conservation focus. Some of the 20% of singleton wetlands providing different habitat and extra invertebrates that were new species or appeared to species, annual variation in wetland conditions be localised (Pinder et al., 2004a) will also require usually causes the long-term species list of a conservation focus, although many are likely to be wetland to be greater than instantaneous lists (e.g. found more widely after further survey. Halse et al, 1993b; Timms, 1998). Provided sources Many of the rare plants, and some rare of colonization exist, or propagules remain at the invertebrates, occurred in naturally saline wetlands. ------Aquatic biodiversity 361

In most G1SeS, whether on private or public land, lkard. 1.5. (1990). /'111111 o!\V,'.;lcrll /\II.;lmllll. Kdngaroo these wetlands were threatened with increased Press, Svdnev. inundation because of salinisation. When Beard, IS (1999). Evolution 01 thc river svstems of tIll' salinisation is the principal threat, rare species south-wcst drainage division, Western Australia usually cannot be protected through small-scale IOllllllllolllic (,;ol/ol 01 \Vc.;lcrll /\II.;lm{lo 82: 1,+7 managenwnt actions aimed at the organisms and 164. their immediate habitat (see Coates and Atkins, BC'lI'd. 1.5. Ch,lpman, I\.R. ,md Cioia, ['. (2()()O). Species 2(01). Catchment-scale solutions (C1arke cl al. 2(02) richness and endemism in thc Western Australian or very expensive localised engineering works flora. 10111'1101 III Bioxcoxmplll/27: 1257-126x. (Froend et aI., 1997) arc required. [klbin. L. (1991). Semi-strong hvbrid scaling: ,1 ncw ordination algorithm. IOllrJlIII 01 S"iclI"c 2: 491-496. Integrating wetland and upland protection Belbin, L. (1993). /'11 IN: pllllcm 1IIIIIIy.;i.; CSl RO, This paper has focussed on protecting Canberra. biodiversity associated with wetlands which, Biological Survcv Committec. (19x4). Thc biological because they arc low in the landscape, arc survcv of the Eastern Coldficlds of Western Austra[ia. disproportionately threatened by salinisation (Halse Part I. Introduction and methods. I';ccol'd.; 01 Illc et 11/., 2(03). However, protection of upland \Vc.;lcrll IIw;11'II1i1l ;\;II1';CIIIII SlIpp{clIICl/l18: 1-19. biodiversity is equally important and BRCs cannot Blinn, D.W" Halse, S,A" Pinder, A,M,. Shic[. R.I, and be selected on wetland values alone. Results from McRae, I,M. (20(H). Diatom and zooplankton terrestrial components of the WBS (McKenzie et a/., communities and environmental determinants in the 2004) should be combined with recommendations Wcslcrn Australian wheatbelt: a rcsponse to about PRWs (Table 5) and species-rich examples of secundarv salinisation. III/dro[lIoloXIII 528: 229· 24x, the identified wetland types (Figure 7) to identify Boesch, D.F, (1977). Application of numcrical catchments of 50,000-]()O,OOO ha with particularly classification in ecologicll investigations of water high biodiversity value. Irreplaceability analysis is pollution, EPA-600/.1-77-0.13, United States Environmental Protection Agencv, Washington D.e. one method of combining datasets of disparate Bowler, I.M, (19x3), Lunettes as ind ices of hyd rologic biodiversity values and Walshe et 11/. (2004) have change: A review of Australian evidence, Proceedillg.; used the survey data to identify potential SRCs that ollhe Royal Sociely ot' Victoria 95: ]47-68. encompass much of the biodiversity of the Brock, M.A, and Lane, I,A,K, (19x.1). The aquatic wheatbelt and south coast and provide the macrophyte flora of saline wetlands in Western framework for landscape-scale conservation efforts. Australia in relation to salinity and permanence, Ilydrohioloxia 105: 6.1-76, Brock, M,A, and Shiel, RJ (19:-:.1), The composition of ACKNOWLEDGEMENTS aquatic communities in saline waters in \Nestern We wish to thank M.R. Williams for statistical Australia, Ifydrohio!ogia 105: 77-:-:4, advice, P. Goia for climatic data from the Cale, DJ, Halse, S.A. and Walker, CD. (20lB), Wetland ANUCUM model, and J.c. Cocking and J.M. Illonitoring in the Wheatbelt of south-west Western McRae for producing the figures. Funding for this Australia: site descriptions. waterbird, aquatic studv was provided as part of the State Salinitv invertebrate and groundwater data. COII.;er('alioll Sciellce Wc.;lcl'II A 11'; I1'111 ia 5: 20-·B5, Strategy. CLuke, CL Ceorge, R,I" Bell, R.W. and J latton, TJ (2002), Drvland salinity in south-western Australia: its origins, remedies, and future' research dil'l'ctions, REFERENCES AII,ll'II/lIlIlII'lIl'IIo! (It'Soill~''.-;eilnh 40: en-I 1.1, Anonvmous. (1996a). 11 .;illlOlullI .,IIIIl'IIII'1I1 Coates, DJ and Atkins, K.A, (2001), Prioritv sl'lting ,1Ild \Vc.;ICrJl /11I.;ll'IIlill. Covernment ot Western Australia, the conSl'l'\'ation of Western Australia's diverse and Perth. highlv endemic flora, C'II-;C['('IIIIOII 97: 251 Anonvmous. (1996b).\Vc.;lcrll 11 11.;1 I'IIlillll ';01111111/ ollillll 263. 1'1011. C;overnment ot \Vestern Australia. Perth. COllllllandl'r, D.l), litil'ld. I.K. Thorpe. PAL. Dalie, R.E., ;\tmeH. Wand Patlerson, BD. (199.1). TIll' medsure of Bird, I.R, and Turner, I,V. (1994) Chlurinl'-.16 and ordl'l' ,md disordl'l' in the distribution ot species III Cclrbon-14 llleasurenwnts on hl'fwrs'llitll' fragmenll'd hdbit,lt. ( 96: .17.1.1:-:2 g 1'0 und w a te I' in [v I·t ia 1'1' p,lleoc h,1 nne I.s Iwa r Atlllar. W. dnd [)dtll'I'son, B.D. (1995). fill' 1I1',lc,{lIl'';, Western Australia. I)wll'ssior\al l\l\,erS 11'IIII'CI'IIIIII'C "0"'111111,'1': II ('1'11111 />il'll pl'l'gl'llIlI, 5.1·60, ot Wl'stern ;\ustralia, Perth, 2lJ.j 1IIIIII'uc,. A[C5 ResceHch [nc, Cra nw r, \ A ,m d 1lob bs, RI. (2002). Lcol og iCill cOllseqlll'nCl's ot ,1Itere'd hvdrologiLal r('glll1t'S in Austin. :vU) dnd [klbill. 1 . (] 9:-:2). A new a[Jprodch to tragmented ecos\'stl'ms in soutlwrn Australia: the species cLlSsiticdtion problcms in floristic ,1I1,)I\SIS and m,magellll'nt ~lI',lfI'" ""- 11.;11'111 11'11'11111111 10111'11011'1 7: 75-:-:9. 27: 5,16- 564. I.I\.E. (1999). 1';1 ,,,A: ologc.;.luart llouse. Perth. 1\1\i.;. I.A" llals.., S.A. ,md hOl'IlL!, I~.II. (2001), l.aLtors 362 S. A. Halse, M. N. Lyons, A. M. Pinder, R J. Shiel

influt'ncing biodiversity in coastal plain wt'tlands of Halse, S.A. (1981). Faunal assemblagt's of some saline southwestern Australia. III B. Gopa!' W.J. Junk and lakes near Marchagee, Western Australia. J.A. Davis (t'dsJ, III (('et/lll1ds: IIssessII/e 11 I. /\uslrallllll Journlll of A11/rllle Illld Fresllil'lller Resellrdl lilllclloll IIl1d collscrullllolI: 89-100. Backhuys, Leiden. 32: 133-142. Diels. L. (1906). Die UOII We';I~Auslrallell lIaIse, S.A. (2002). Diversity of Ostracoda (Crustacea) in ,;udllch de,; Wellderkrel,;es. Engelmann. Leipzig. inland waters of Western Australia. VcrhalldlulIgell Dogramaci, S., George, R., Mauger, G and Ruprecht, J. IlIlerllallollllle VerellllgulIg fur Iheorelische ulld (2003). Waler /Jillallce alld salllllly Irelld. TooJi/JIII allgczl'lllldle Lilllllologle 28: 9 I 4-91 8. calchll/elll. Weslerll Au,;lralla. Department of Halse, S.A., Call', D.J., Jasinska, E.J. and Shie!, R.J. (2002). Conservation and Land Management, Perth. Monitoring change in aquatic invt'rtebrate Doupe, R.G. and Horwitz, 1'. (1995). The value of biodiversity: sample sizt', faunal elements and macroinvertebrate assemblages for determining analytical methods. Aquallc Ecology 36: 395-410. priorities in wetland rehabilitation: a case study from Halse, S.A., McRae, J.M. (2001). Calal1loecla Iri/o/JI/la n sp Lake Toolibin, Western Australia. jourJIlIl of Ihe Royal (Copepoda: Calanoida) from salt lakes in south~ Soclely of WeslerJI Au,;lralia 78: 33-38. westt'rn Australia. Joumlll of Ihe ROl/al Society of Fleishman, E., Betrus, CJ., Blair, RB., MacNally, R. and Weslem Au,;lralia 84: 5-1 I. Murphy, 0.0. (2002). Nestedness analysis and liaIse, S.A., Pearson, C.B., McRae, J.M. and Shiel,R.J. conservation planning: the importance of place, (2000a). Monitoring aquatic invertebrates and environment, and life history across taxonomic waterbirds at Toolibin and Walbyring Lakes in the groups. Oecologlll 133: 78-89. Wt'stern Australian wheatbelt. joumal of Ihe Royal Frey, D.G. (1991). The species of Pleuro.lus and three Soclely of WeslerJI Auslralill 83: 17-28. related genera (Anomopda, Chydoridae) in southern Halse, S.A., Pearson, C.B. and I'atrick, S. (1993a) Australia and New Zealand. Records oflhe Auslrallall Vegetation of dt'pth~gauged wetlands in nature Museul1l 43: 291-372. reserves of south~west Western Australia. Technical Froend, IU-I., Halse, S.A. and Storey, A.W. (1997). Report 30. Department of Conservation and Land Planning for the recovery of Lake Toolibin, Western Management, Perth. Australia. Wellalld,; Ecology alld Mallagel1lelll 5: 73-85. Halse, S.A., Pearson, GB., Vervest, R.M. and Yung, F.H. Froend, R.H., Heddle, E.M., Bell, 0.1'. and McComb, AJ. (1995). Annual waterfowl counts in south~west (1987). Effects of salinity and waterlogging on the Western Australia 1991/92. CALMSclellce 2: 1-24. vegetation of Toolibin Lake, Western Australia. Halse, S.A., l\uprecht, J.K. and I'inder, A.M. (2003). Auslraliall jourJIal of Ecology 12: 281-298. Salinisation and prospects for biodiversity in rivers Froend, RlI. and McComb, AJ. (1991). An account of the and wetlands of south~west Western Australia. decline of Lake Towerrinning, a wheatbelt wetland. Auslralillll jourJIlIl of Holalll/ 51: 673-688. Journal of Ihe Royal Socletl/ of WeslerJI Auslralia 73: 123­ Halse, S.A., Shiel, R.J., Storey, AW., Edward, D.H.D., 8. Lansbury, I., Cale, D.J. and Harvey, MS. (2000b). Froend, R.H. and van del' Moeze!, P.G. (1994) The impact Aquatic invertebrates and waterbirds of wetlands and of prolonged flooding on the vegetation of rivers of the southern Carnarvon Basin, Western Coomalbidgup Swamp, Western Australia. jourJIal of Australia. Records of Ihe Weslem Auslralillll Museul1l Ihe Royal SoclL'ly ofWeslerJI Au,;lralia 77: 15-22. Supplell/elll 61: 217-267. Gaston, K.J. (2000). Global patterns in biodiversity. Nalure Halse, S.A., Williams, M.R., Jaensch, R.I'. and Lane, 405: 220-227. J.A.K. (1993b). Wetland characteristics and waterbird Geddes, M.C, De Deckker, 1'., Williams, W.D., Morton, use of wetlands in south~western Australia. WildliFe D.W. and Topping, M. (198I). On the chemistry and Research 20: 103-126. biota of some saline lakes in Western Australia. Hammer, U.T. (1986). Salille lake ecosl/slell/s of Ihe world. Hydro/Jlologll/ 82: 20I-222. Junk, Dordrecht. Gentilli, J. (1972) Auslrallall clll1Iale pal/erns. Nelson, Harper, RJ. and Cilkes, R.J. (2003). Aeolian influences on Melbourne. the soils and landforms of the southern Yigarn Craton George, R.J., Clarke, CJ. and Hatton, T.J. (2002). of semi~arid, southwestern Australia. Geol1lorphology Computer modelled ground water response to 59: 215-235. recharge management for dryland salinity control in Hart, B.T., Bailey, P., Edwards, R., Hortle, K., James, K., Western Australia. Ad1'allces III Ell1'lrolll1lelllal McMahon, A., Meredith, C and Swadling, K. (1991). MOllllorlllg alld A10delilllg 2: 3-35. A review of the salt sensitivity of the Australian Ceorge. I\.J., McFarlane, DJ and Speed, RJ. (1995). The freshwater biota. Hydro/Jlologla 210: 105-44. consequences of a changing hydrologic environment Hingston, F.J. and Gailitis, V. (1976). The geographic for native vegetation in southwestern Australia. III variation of salt precipitated over Western Australia. D.A Saunders, J.L. Craig and E.M. Mattiske (eds). Au,;lralillll Journal of 5011 Resellrch 14: 319-335. Nalure collscrUllllolI 4: Ihe role of lIelworks: 9-22. Surrey Hopper, S.D. (1979). Biogeographical rates of speciation Beatty & Sons, Sydney. in the southwest Australian flora. All/l/IIII l\e1'lew of Cibson, N., Keighery, GJ., Lyons, M.N. and Webb, A. alld 10: 399--422. (2004). Terrt'strial flora and vegetation of the Western Hopper, S.D., Brown, A.I) and Marchant, N.G (1997). Australian wheatbelt. I\ecor,(s of Ihe Weslem Auslraliall Plants of Western Australian granite outcrops. jourJIal lviuseUlI1 Supplelllelll 67: 139-189. of Ihe Royal of Wes/ern A 1I,;lralill 80: 141-158.

7 _ Aquatic biodiversity 363

1,H'nslh, R 1', Vc'nes!, 1\1\1. ,1nd I kWISh, \:11 (I '!~~) N, \1 Jt ll' rnll' il'r, 1\. A., \:1 itll' rnwin, e.C, d a vV,lterbird surveys ot wt'tL1l1d n,ltun' ITSl'rves In hll1ll'S,l, CA.B. and Kl'I1!.s, I (2000). Biodi\l'rsitv south,western I\ustrali,): 19~1-~'i. Report 30. I\OV,11 ho!.sl'o!.s lor Ul\lSl'rvation I'rioritil's. ,'JIIIIIII' 403: S'i.1­ Austr,llasian Ornithologists Union, \:klbuurne. S~S. lustus, I. ,1nll sarkar, S. (2002). Ihe princq,I,' ot Nicholls, 1\.0. (19S9). Ilow to m,lkJ' """"1-'.'"'' surn'vs go compkmentaritv in the ut reserle nt'twurks tu turtlll'r with ised Illll'ar mudl'!.s. cunSl'r\'t' biudiversitv: ,1 l,relimin,Hv histurv. 1011111111 C'OIl"I'I('IIIIOII 50: 51·· 75. ,11 BI'''II''1I11 27: 421-4.15. Norman, 1.1. (19~3). Cn'\' Tl'a!, Chl'stnut TI',ll, ,1l1d Pacific K,n, W.R, Ilalsl" s.A., scanlun, \:1.1). and Smith, \:11. Black Duck at ,I s,lline habitat in Vittoria. EIIIII 83: (20l1l). Distribution and el1\'irunmenLl1 tulerdnces uf 262270. aquatic ma(Tuinvertebrdte families in tIll' agriniltur,ll I'indl'r, A.M., Halsl', 5.1\., Md\,ll', l.:vl and shil'l, R.J. /une of suuthwl'stern Australia. 1011111111 of Iltl' ['Jorllt (2004). Aquatir invl'rtl'bratl' assemblagl's of wl'tlands 1~2-199. AIIICllmll BOlllloloSlll11 20: ,llld rivers in the wl1l'atlll'lt rl'giun ot Wl'stl'rn Keigl1l'rv, C (2001). Whl',ltbelt wonders under threat. I\UstLllia PI'IIIIt!, 01 lill' WI'''II'I'I/ 1I"lmllllll :\111."'1/111 011/1'11."101'<' 16 .1742. 67: 7-37 1,1111', I.I\.K. (19~5). Important aspl'cts ut duck hunting in l'inder, I\.M., lIaise, 5.1\., Mc!\,1l', I.M. and 5hil'!, RI Australia, with particuldr reterence tu Western (200'i). Influl'nn' ot salinitv on thl' occurrencl' of l\ustrali,l. III 1.1. Bunning (l'd.L of lite whl'atbelt aqualic invertebrates. lIydl'o/Jiologill (in <1/,'"1'0""1/11 Oil /!inl" IIlId IIll11l11Sl'llIelll, 1011l11lIle"'lIlrs 1983: I'rl'ss). 2~ 1-307. Witwatersrdnd Bird Club, luhannesburg. Pindl'r, A.M., lIaise, S.A., Shil'l, R.I., Cale, D.I. and I.vuns, M.N., Cibsun, N., Keiglll'ry, Cl. and Ivons, SD. McRal', I.M. (2002). I Jalophilic invertl'brates uf salinl' (20()4). The \vetland flora and vcgl'tation uf the suuth wl'tlands in thl' whl'atbl'lt of south-wl'stl'rn AustralIa. wcst ,lgricultural /une of VVeskrn !\ustralia Pelord, ,'1'/11/110/111/<.'1'1/ del' 1IIII'I'I/ll1lOIlllle of Ille 1I>llIIlllIiI :\/111,,'11111 SUPI,!L'mcnt Nu 67: 28: 16~71694. ()( 10-000 Pindl'r, ;\\:1, Halsc, 5.A., shil'l, KI. and \:1cRae, I.M. \:blv, E.J. and B'lvlv, I.A.E. (1991). F,lCtors influencing (2000). (;rallitc outcrop puols in south-westl'rn patterns uf Australasi,lll centropagid Australia: foci for divnsification and retugia for cupepods. 1011111111 of 18: 455-61. aqu,ltic invl'rkbratl's. jOlll'l/1I1 of 1111' 1\111/111 of tvlaly, E.I., Halse, S.A. and Maly, M.I) (I Distribution Wl'sll'lII AI/slmlill 83: 117-129. and incidence patterns uf BOl'lkcllll, C1I1111110e1'll1, and l'n'ssl'v, R.L., lohnson, I.R. and Wilson, P.D. (1994). f[ellllZ,ol'ckelll1 (Cupepuda: Calanuida) in Western 5hadl's of irrl'placl'ability: towards a ml'asurl' of thl' Australia. ;\;1111'111e I1l1d Frcs/1Z1'I11C1 [\I'''l'lIr1'1t 48: 615-621. contribution of sites to a rl'sl'rvation goal. /)111,117 ""'-'1,11/ Margules, CR. and Pressey, R.L. (2000). Review article: COlIsel'mlioll 3: 242-262. systematic conservation planning. Nalllre 405: 243- Rl'migio, LA., Hl'bl'rt, PD.N. and savagl', A. (2001). ')r-, ..... :)~) . Phvlogenl'tic relationships and rl'mark,lbll' radiation McKell/ie, N.I., Belbin, L., M'lrgules, CR. and K,'igherv, in I'lImrll'lllill (Crustacl'a: Anostrara), thl' l'ndl'mic C;·I· Selecting representative resel'\'e systems brinl' shrimp of Australia: l'vidl'ncl' from in remote area: a case study in the Nullarbor region, mitochondrial DNA sequl'ncl's. 10111'1/111 of I!II' Western Australia. COlhelTllllll1I 50: 239,261. I.i,lll['i/II 74: 59--71. \:lcKen/ie, N.L., Halsl', S.A. and C;ibson, N. (2000). Some Roshil'r, D.A., Robl'rtson, A.I, Kingsford, R. r. ,1l1d Grl'en, g,lpS in the reserve system of the southern Carnarvon D.G. (200 I). Continl'nt,ll-scale inkrilctions with Basin, Western Australia. I\ecords of Iltl' We"lcrn temporary resourcl'S may l'xplain thl' paradox uf A IISIIllI ill 11 M liSI'll III 511 ppIn11 I'll I 61: 547-567. large pupulatiulls ot dl'sl'rt watl'rbirds in Austral id. McKell/il', N.!., lohnston, R.B. ,lnd Kendrick, I'C;. (Eds) l.lIl1d'lll/1[' 16: 547-556. (1991) AII"lmlll1. surrev Beattv, 5alama, R.B. (199,+). Thl' l'\olution of salinl' lakl's ill till' Svdnev. rl'lilit drain,lgl' ot thl' Yilg,nn Rin'r, Weskrll i'vlcKen/ie, N.I. ,1Ild Robinsun, I\e. (l'ds) (19~7). A Austrdlid. III R. Rl'llaut ,1Ild W. last (l'ds), SIIITel/ ,,/ Ill,' Nllllllr/,or SOIlIIt IIlId IIl1d of 1/I0dl'I'I/ IIl1d 111111"111 ivV,'"I,'rll Irlllll/ III South l\ustr,llian 1'11111111111011 :i(}: IWJI99. Departnll'nt ot Fnvironn1l'nt and I'ldnning, Adelaide. luls,l,Okldhoma. \:kKen/ie, N.L., C;ibson, N., Keighel'\, dnd Rolfe, IK C,rholil'ld, N.I., Ruprl'cht, IK and Loh, Le. (19~~). fhl' (2004) 1',ltterns in the blodiversitv of tnrestridl impatt of agricultural dl'vl'lopml'nt on till' salinitl· 01 environnll'nts in tIll' Western Austr,llian Wlw,ltbelt. SUrfarl' wall'r l'l";'Jurrl'S 01 south,wl'st \Vl'Sll'1'Il /\"«1nl" of Ihe tVe"IClII AII"IIIIIIIIII ;\111'[1'11111 /\ustralia. W5 27. Watl'r 01 Wl'stern 67: 293-335, l\ustra!i,l, Pl'rth.

(1967). lakrites ,1l1d soils 111 5rotts, D. and Drielsm'l, \:1 (201l.1) suuthwestnn Australia. III I.N knllings alld I. \. Irame\\orks tor UJI1sl'l'vation planll1l1g; all Mabbutt ,llIdl'" 1I"lllllllllllld tor tauna spatial distributiuns C;IIIIII'II: 211·2.10. l\ustralIan Natiollal Universitv, et l/ I";,'li',i1/011 Callbl'rra. 82F 254. \1.1. (I 5al1l1isat!on in the southwest ut 5hl'phnd, D.I'., l\cestoll, (;.R. and Ilol'kins, I\.I.M. Westl'rn Austr,llia. SI'i!/(!1 9: 269 72. (21l1l1). Natl\l' \egdatiul1 in Wl'skrn Australia. 364 S. A. HaIse, M. N. Lyons, A. M. Pinder, R. J. ShieI

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