Appendices 1. Station summaries 2. Plant species lists (i) Plant species recorded in the survey area (ii) Common plants of the Bunda Plateau in the survey area (iii) Common Nullarbor coastal zone plants in the survey area 3. Land system maps 349 350 Table 30 Categories of pastoral potential for land Appendix 1—Station systems summaries Carrying capacity in good condition Category Station reports are presented alphabetically as (ha/dry sheep equivalent) tables for the 20 stations in the survey area. High 6–9 ha/dse Each station report consists of preliminary Moderately high 10–14 ha/dse information including the land conservation Moderate 15–19 ha/dse district and shire in which the station falls. The Low 20–29 ha/dse area included is that which was legally defined Very low ≥ 30 ha/dse as part of the pastoral lease(s) comprising each station at the time of the survey. The area The potential carrying capacity indicates the does not include reserves, freehold land and total grazing pressure a habitat can maintain on Unallocated Crown Land within the pastoral a sustainable, long-term basis from a com- lease. The station area is calculated from munity of herbivores. The potential carrying digitised mapping and is more accurate than capacities are given in dry sheep equivalents the current stated legal area. (dse). One dry sheep equivalent is the feed Each station report consists of three tables. energy required by a 45 kg liveweight Merino The first table deals with land types, i.e. groups wether, to maintain its liveweight (Newman & of similar land systems. It gives a general Chapman 2001). The impact of other herbi- impression of the types of country and their vores can be converted to different types and extent on each pastoral lease. Land types and classes of stock using dse conversion rates in land systems are shown on the accompanying Table 31. map sheets. The second table provides Table 31 Relative feed requirements expressed as dry sheep more detailed information at a equivalents (dse) (adapted from Cooke-Yarborough 1990; Van Vreeswyk & Godden 1998; Dorges, Heuckle & Dance 2003). land system scale. For each land system (sorted into groups Sheep (Merino) dse according to pastoral potential) 1 Merino wether (~ 45 kg) 1.0 there are details on area, 1 Merino ewe (average for ewes producing 50% lambs) 1.3 number of traverse assess- 1 Merino weaner (to 1 year) 0.7 ments and condition based on the traverse assessments. 1 Merino ram 1.5 Sheep (meat sheep) The third table summarises the second table. Information is 1 meat sheep wether (~ 45 kg) 1.0 presented for land systems 1 meat sheep ewe (average for ewes producing 50% lambs) 1.4 grouped according to pastoral 1 meat sheep weaner (to 1 year) 1.0 potential. 1 meat sheep ram 1.5 Finally, summarised pastoral Cattle resource condition information 1 steer/bullock (~ 270 kg) 7.0 for the station as a whole is 1 year old steer or heifer (~ 140 kg) 6.0 presented. This includes the 1 cow (average for cows producing 50% calves) 9.8 proportion of good, fair and 1 weaner 4.2 poor condition vegetation condition and the potential 1 bull 10.5 carrying capacity. Other grazers 1 camel (450 kg—635 kg) 11.0–14.0 Throughout the station reports the figures have been rounded 1 horse (450 kg—635 kg) 11.0–14.0 to whole numbers. 1 kangaroo 0.7 For the purpose of this report, * 7 dse = 1 cattle unit (cu) the categories of pastoral potential, based on estimated carrying capacity, have been adopted as shown in Table 30. 351 For each land system the calculated potential (Holm 1994), Yerilla (Fletcher 1995), Coodardy carrying capacity (Pcc) was based on the (Yan, Holm & Mitchell 1996) or other literature proportion of its component land units and the (Lay 1975). associated vegetation habitat types in good Productivity data was not solely used to deter- condition. The potential carrying capacity mine carrying capacity estimates; climate, indicates that which each land system can palatability and durability of the vegetation were support on a long-term basis without damage also taken into account. Over recent decades to the rangeland resource. The potential carry- throughout southern Australia the intensity and ing capacity is derived from the land unit area frequency of exceptionally hot years have been on each lease and estimated stocking rates. increasing and this trend is expected to The potential carrying capacity assumes the continue. The projections of reduced annual capacity of the lease to produce forage has not rainfall averages are likely to result in more been reduced and that water point distribution exceptionally dry years and fewer exceptionally is sufficient to ensure that all pastures on the wet years (Hennessy et al. 2008). Therefore lease are able to be grazed throughout the this probability has been factored into the year. Table 32 shows the potential carrying calculated potential carrying capacities for capacity for each of the Western Australian Western Australian Nullarbor land systems. Nullarbor land systems in good vegetative Whilst it is likely that total herbivore grazing condition. Areas of lake bed have been pressure may exceed those stated as the extracted from the land systems in which they potential carrying capacity during exceptionally occur and have been given a carrying capacity wet years the landscape cannot support such of zero. numbers on a long-term basis once average It is the lessees’ statutory obligation to ensure drier seasonal conditions return. Carrying that overgrazing of pastures does not degrade capacity estimates were checked against the the rangeland resource (inferred in Land opinions of experienced rangeland advisors Administration Act 1997 Section 108 Sub- and past lease inspection reports. section (4)). The actual number of stock run at The vegetation condition summaries are based any one time will vary according to factors such on the composition and condition of the as: perennial vegetation. The vegetation condition • current seasonal conditions classes are defined as: • history of seasons prior to current season Good For the land unit-vegetation type, the • grazing pressure from non-domestic composition and cover of shrubs, herbivores perennial herbs and grasses is near • stock distribution optimal; free of obvious reductions in • class and status of stock palatable species or increases in • range condition trend management unpalatable species. Perennials present requirements. include all or most of the palatable species expected; some less palatable Historical information concerning the carrying or unpalatable species may have capacity of Nullarbor pastures is limited. increased, but the total perennial cover Nullarbor potential carrying capacities have is not very different from the optimal. been primarily based on carrying capacity information determined during the 1974 Fair Moderate losses of palatable perennials Western Australian Nullarbor Plain survey and/or increases in unpalatable shrubs (Mitchell, McCarthy & Hacker 1979) in or grasses, but most palatable species conjunction with information provided by past and stability desirables still present; and present Nullarbor pastoralists. Where foliar cover is less than on comparable similarities existed with habitat types from sites rated very good or good unless previous southern rangeland surveys (Curry et unpalatable species have increased. al. 1994; Pringle, Van Vreeswyk & Gilligan Poor Conspicuous losses of palatable peren- 1994; Payne et al. 1998) carrying capacity nials or few, if any palatable perennials information was compared against these remain, foliar cover is either decreased locations. In such cases the potential carrying through general loss of perennials or is capacities had been based on results from increased by the invasion of grazing trials such as those at Boolathana unpalatable species. 352 Rangeland forage availability is heteroge- Table 32 Western Australian Nullarbor land system neous in space and variable over time, pastoral potential and carrying capacity (ha/dse) therefore carrying capacity will vary Good condition Pastoral potential Land system correspondingly. This suggests that it is (ha/dse) inappropriate for the potential carrying Moderately high Moodini 11 capacity figures alone to be used for Moopina 11 commercial or regulatory purposes. Woorlba 11 Individual station reports presented in this Arubiddy 12 Koonjarra 12 report are for the following leases: Lefroy 12 Arubiddy, Balgair, Balladonia, Boonderoo, Mundrabilla 12 Gunnadorah, Kanandah, Kinclaven, Nanambinia 12 Koonjarra, Kybo, Madura, Moonera, Thampanna 12 Mundrabilla, Nanambinia, Noondoonia, Weebubbie 13 Point Culver, Pondana, Rawlinna, Vanesk, Balgair 14 Virginia and Woorlba. Chowilla 14 Gafa 14 Kanandah 14 Kybo 14 Moonera 14 Pondana 14 Reid 14 Seemore 14 Shakehole 14 Vanesk 14 Virginia 14 Moderate Balladonia 15 Bullseye 15 Haig 15 Kinclaven 15 Morris 15 Nightshade 15 Nurina 15 Roe 15 Skink 15 Caiguna 16 Carlisle 16 Kitchener 16 Lowry 16 Naretha 16 Nyanga 16 Oasis 16 Colville 17 Gumbelt 17 Jubilee 17 Kyarra 17 Boonderoo 19 Low Rabbit 20 Ponton 21 Culver 23 Damper 23 Toolinna 24 Wurrengoodyea 25 Very low Baxter 30 Wylie 30 Bilbunya 50 Delisser 50 Zanthus 50 353 References Newman, P & Chapman, G 2001, Grazing benchmarks and management in eastern Cooke-Yarborough, RE 1990, ‘Mensuration, Australia, a report for the Rural Industries Chapter 37’, in The Manual of Australian Research and Development Corporation Agriculture, 5th edn, RL Reid (ed.), (RIRDC) by Resource Consulting Services, Butterworths Pty Ltd.