The Charcoal Tank Nature Reserve is a protected nature reserve in the central western region of New South Wales, Australia. The reserve is situated south of West Wyalong and may be accessed via the Newell Highway and The Charcoal Tank Road. The reserve is an important refuge for native flora and fauna in a highly fragmented landscape, one in which the majority of the original vegetation has been removed.
Description
The land surrounding the reserve has been extensively altered through agricultural practice and the development of roads. As a remnant in a highly modified landscape, the reserve's vegetation is significant to the region as it includes critically endangered mallee and mallee–broombush in the absence on Spinifex; in total there are only three protected areas within New South Wales containing this now rare vegetative structure. The International Union for Conservation of Nature’s category for the reserve is Ia, a protected area that is dedicated to conserving biodiversity and minimising disturbances by limiting human access.
The reserve is relatively flat with a dry, red, loamy clay top soil; three man-made dams are situated along a drainage line that runs the length of the reserve.
The traditional landowners of the region are the Wiradjuri people, inhabiting the region for over 40,000 years prior to European settlement in the area. Little is known about the Wiradjuri people's use of the reserve except that it was likely a place for gathering food. After European settlement but prior to its listing as a Nature Reserve the site was used as camp on the traveling stock route and as a public watering place. In 1960 it became NSW Wildlife Refuge No. 2 but was still available for use as a watering ground and camp. The area officially became The Charcoal Tank Nature Reserve in 1966; prior to its change in status a rest stop was cut into a portion of the reserve along the Newell Highway and remains there today.
Climate
The region's climate is considered semi-arid with hot dry summers and cold winters.Australian Government 1, Bureau of Meteorology. 2014. Climate Classifications: http://www.bom.gov.au/jsp/ncc/climate_averages/climate-classifications/index.jsp Elevation is above sea level with the mean minimum temperature and mean maximum , mean relative humidity ranges between 48% in summer to 90% during winter with mean wind speeds ranging from .Australian Government 2, Bureau of Meteorology. 2014. Climate Statistics for Australian Locations: https://www.bom.gov.au/climate/averages/tables/cw_050017.shtml Annual rainfall over the past 13 years has ranged from per annum; the region has experienced severe periods of drought within the last 30 years.Australian Government 3, Bureau of Meteorology. 2014. Monthly Rainfall West Wyalong Airport: http://www.bom.gov.au/jsp/ncc/cdio/weatherData/av?p_nccObsCode=139&p_display_type=dataFile&p_startYear=&p_c=&p_stn_num=050017
Ecology
The reserve has a high level of biodiversity for its size and is an important remnant for a range of flora and fauna, including some nomadic and migratory birds species. Due to its size and isolation the reserve is only able to provide somewhat limited resources to support large numbers of resident animal species. Fire history for the reserve prior to 1966 is not well documented but evidence at the site suggests it is long-unburnt and recent records show fire has not occurred there since it was announced as a reserve in 1966.New South Wales Government: Office of Environment and Heritage: Nature Conservation. 2014. Charcoal Tank Reserve Fire Management Strategy: http://www.environment.nsw.gov.au/firemanagement/TheCharcoalTankNRfms.htm
Flora
Even though the reserve is small there are three distinct communities of vegetation. The dominant community is mallee-broombush made up of broombush, blue mallee, green mallee and bull mallee. Two notable native shrubs sharing the mallee-broombush community are purple kunzea and dagger-leaved wattle. The second largest group of vegetation is a eucalyptus-callitris mix; including inland grey box, mugga ironbark, and black cypress pine. The eucalyptus and callitris community has a well-developed understory that includes native shrubs such as cough bush, quandong and hakea wattle. Understory and groundcover in other areas of the reserve has been lost or badly degraded. The smallest community of vegetation is made up of black cypress pine, Dwyer's red-gum and currawang.
The dominant community of mallee and broombush is listed as critically endangered under the NSW Threatened Species Conservation Act, with only two other Nature Reserves in NSW protecting similar communities.New South Wales Government: Office of Environment and Heritage: Nature Conservation. 2011. Mallee and Mallee-Broombush dominated woodland and shrubland, lacking Triodia, in the NSW South Western Slopes Bioregion - critically endangered ecological community listing. http://www.environment.nsw.gov.au/determinations/malleeandmalleebroombushFD.htm Mallee and broombush have been extensively harvested in the region since European settlement.Priddel, D., Wheeler, R., Copley, P. 2007. Does the integrity or structure of mallee habitat influence the degree of fox predation on Malleefowl (Leiposa ocellata), Emu. 107: 100-101, 104-106.
Fauna
Birds represent the largest number of vertebrate species occurring within the reserve with over 165 species identified; 96 species have been banded and released as part of a long-term monitoring study in the reserve.Clayton, M. 2014. ACT Regional Organiser, Australian Bird and Bat Banding Scheme. Personal Communication. Some of the reserve's breeding residents such as brown treecreeper and varied sittella are listed as Vulnerable under the NSW Threatened Species Conservation (TSC) Act 1995. Data from the long-term bird banding project shows a decrease in the number of brown treecreepers present. There are twenty other birds that utilize the reserve that are also listed as Vulnerable under the NSW TSC Act; some examples are painted honeyeater, superb parrot, regent honeyeater and the swift parrot. Under Australia's national Environment Protection and Biodiversity Conservation Act 1999 the regent honeyeater and the swift parrot are listed as endangered and the superb parrot as vulnerable.Australian Government 4, Department of the Environment. 2014. EPBC Act List of Threatened Fauna: http://www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl?wanted=fauna
Sadly, species such as malleefowl, Gilbert's whistler, southern scrub robin and crested shrike-tit have become extinct from the reserve in the past 30 years; the last crested shrike-tit banded in the reserve was in 1997.Ewin, P. 2007. 4. Malleefowl in New South Wales: Review of Past and Future Actions. Page 3. The disappearance of the malleefowl not only in the reserve but the surrounding region is due to a number of pressures; these include predation by red fox and feral cat, fragmentation and loss of habitat, isolation, competition and degradation of habitat by domestic livestock and introduced vertebrates such as European rabbit and feral goats.Priddel, D., Wheeler, R. 1994. Mortality of Captive-raised Malleefowl, Leipoa ocellata, Released into a Mallee Remnant within the Wheat-belt of New South Wales, Wildlife Research. 21: 543, 551. More recently the reserve's long-term bird monitoring study has recorded a decline in species that were previously abundant or regular visitors to the reserve, this includes species such as the grey-crowned babbler, shy heathwren, diamond firetail, and eastern yellow robin
Other fauna found in the reserve includes mammals such as eastern grey kangaroo, swamp wallaby, short-beaked echidna and sugar glider. Five amphibians are known to occur in the reserve and nine species of reptile such as lace monitor and eastern brown snake. Some invertebrates found in the reserve are common freshwater yabby and at least nine species of butterfly including spotted Jezebel and Australian painted lady.Bond, S. 2014. Personal Communication. The reserve may also be important to the long-term survival of the locally threatened butterfly western dusky-blue, this species is dependent upon Mallee for its survival and has been located in remnant mallee habitat close to West Wyalong.Braby, M. F., Edwards, T.D. 2006. The butterfly fauna of the Griffith district, a fragmented semi-arid landscape in inland New South Wales, Pacific Conservation Biology. 12: 1,7-8.
Vertebrate pest species recorded infrequently in The Charcoal Tank Nature Reserve include cat, red fox, common starling, European rabbit, European hare, house mouse and feral pig.
Environmental threats
Due to its small size and isolation in a fragmented landscape The Charcoal Tank Nature Reserve's structure and biodiversity are at risk from threatening processes such as climate change, edge effects, pest species, pollution, high intensity fire and further clearing of roadside and patch remnants in the region. Any of these threatening processes can have serious impacts on biodiversity but they are rarely encountered in isolation having a compounding effect on individual species and ecosystems as a whole.
Fragmentation has isolated the reserve from other remnant patches making it difficult for species to move through the landscape. This places species at greater risk of local extinction by preventing range expansion and therefore decreasing genetic diversity and trapping species in areas without sufficient resources.Ford, H. A., Barrett, G.W., Saunders, D.A., Recher, H.F. 2001. Why have the birds in the woodlands of Southern Australia declined? Biological Conservation. 97: 71-74, 76-79, 81-82.Driscoll, D. 2007. The conservation challenge of sustaining spatially dependent evolution, Pacific Conservation Biology. 13: 84. Once a species becomes locally extinct re-colonisation through immigration across a fragmented landscape is highly unlikely. If species are forced to move across a fragmented landscape they are at greater risk of predation or collisions with vehicles; this is especially the case for species in the reserve which is bordered by the Newell Highway
Roadside vegetation in NSW is now extremely important to the survival of many species that rely on them as the only corridors to larger remnants; this includes species found in the reserve. Small remnants such as The Charcoal Tank Nature Reserve and roadside strips are under increased pressure from edge effects as they have smaller interior habitats. The reserve's edges are linear and artificial making it more susceptible to degrading processes including severe weather events, erosion, insecticidal drift from neighbouring properties, select species dominance, grazing by neighbouring domestic livestock and invasion of pest species.Briggs, S.V., Seddon, J.A., Doyle, S.J. 2007. Structure of bird communities in woodland remnants in central New South Wales, Australia, Australian Journal of Zoology. 55: 35, 38. Predation of bird nests along artificially created edges in Mallee is higher than naturally occurring Mallee edges. Gully erosion in the west of the reserve is a long-standing problem, caused by runoff from the cleared surrounding paddocks and the artificial drainage line to dams. The reserve becomes a sink for the cleared surrounding landscape with topsoil disturbance and potential pollutants and seeds of pest plants entering the reserve.Munoz-Robles, C., Reid, N., Tughe, M., Briggs, S.V., Wilson, B. 2010. Soil hydrological and erosional responses in patches and inert-patches in vegetation states in semi-arid, Australia, Geoderma. 160: 524.