Conservation Advice Eucalyptus Recurva Mongarlowe Mallee

Conservation Advice Eucalyptus Recurva Mongarlowe Mallee

The Minister approved this conservation advice on 26/3/2015 and transferred this species from the endangered to the critically endangered category, effective from 9/4/2015. Conservation Advice Eucalyptus recurva Mongarlowe mallee Taxonomy Conventionally accepted as Eucalyptus recurva Crisp (Crisp, 1988). Conservation status Critically endangered: Criterion 2 B1, (a),(b)(i)(ii)(iii)(iv)(v); Criterion 3 B,(a),(b)(i)(ii)(iii)(iv)(v); Criterion 4 (a). Species can be listed as threatened under state and territory legislation. For information on the listing status of this species under relevant state or territory legislation, see http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl Reason for conservation assessment by the Threatened Species Scientific Committee Eucalyptus recurva was listed as endangered under the predecessor to the Environmental Protection and Biodiversity Conservation Act (1999) (EPBC Act), the Environment Protection Act, and transferred to the EPBC Act in June 2000. This advice follows assessment of information gathered through the Commonwealth’s Species Information Partnership with NSW, which is aimed at systematically reviewing species that are inconsistently listed under the EPBC Act and the relevant State list. Description The Mongarlowe mallee is a multi-stemmed mallee eucalypt. Individuals grow between 1.5 m and 4.2 m in height. The stems have smooth, orange-brown to grey bark and arise from a substantial lignotuberous root system, which can be up to 7.5 m x 12 m in diameter. Adult leaves, 2.8 cm long and 0.7 cm broad, are opposite (i.e. two leaves arise at the same node, on opposite sides of the stem) and have many oil glands. The adult leaves are narrow-elliptic in shape, tapering at both ends, with the tips conspicuously curved downwards. Seedling leaves, 1.3 – 3.0 cm long and 0.7 – 1.6 cm wide, are opposite, broad elliptic to obovate in shape with a blunt leaf tip. The Mongarlowe mallee has white flowers, approximately 5.5 mm long, which are arranged in clusters of three on a common stalk. The fruits of the Mongarlowe mallee are depressed-hemispherical woody capsules (gum-nuts). Flowering occurs for a period of approximately two weeks, usually commencing in the second week of January (DECC, 2010). Distribution The Mongarlowe mallee is known from four sites within the Southern Tablelands of NSW. Three of these sites are located near Mongarlowe and one is near Windellama (approximately 30 km from the Mongarlowe sites). There are six known plants, one at each of the three sites near Mongarlowe and three individuals at the site near Windellama (DECC, 2010; NSW OEH, 2012a). The three sites near Mongarlowe each support a single plant (each plant is approximately 2 km apart) and the site near Windellama supports three individuals, two are 10 m apart and one is approximately 40 m from the other two. It is possible that two plants located near Windellama, located 10 m apart, are identical genotypes that originated from a common rootstock and spread in different directions. The first botanical specimen of this species was collected from one of the Mongarlowe plants in 1985 and the species was described in 1988. The other two Mongarlowe plants were discovered in 1990 and 2001 respectively, and the three plants at Windellama were discovered in 1994, 2001 and 2010 respectively (DECC, 2010). Eucalyptus recura (Mongarlow mallee) Conservation Advice Page 1 of 8 The species’ extent of occurrence is no more than 30 km² and its area of occupancy is 16 km² (NSW OEH, 2012b). All occurrences of the species are within largely uncleared land that is unsuitable for agriculture, therefore it is not likely that it has been been reduced in numbers through human activities such as land clearance (DECC, 2010). The species appears to be relictual. Eucalyptus recurva is not known to occur in any conservation reserves in New South Wales (NSW OEH, 2012b). Cultural Significance Not known. Relevant Biology/Ecology The Mongarlowe mallee is found in low heathland and in some cases at the margins of heathland and adjacent low woodland. All sites are on gentle slopes, with shallow soil consisting of pale-grey sandy loam overlying white or grey clay (DECC, 2010). The size and spread of the lignotubers (woody underground structures) suggests that the existing plants are of considerable age, probably several hundred years (hence the species is also commonly known as the “Ice Age Gum”). It is considered possible that all six plants may continue to live several hundreds of years in the absence of threats. Of the six mature individuals, four are known to have flowered in at least some years and two have not yet been observed to flower or bear fruit capsules. No seedling establishment has been observed at any of the known sites (DECC, 2010). Persistence of the species appears to depend on the possibly limited reproductive capacity of the six remaining adult plants. The Mongarlowe mallee is almost certainly insect pollinated, with visitation of the flowers by several species of beetles, moths, flies, hover flies and native bees being observed during the flowering period. Rates of natural seed set are extremely low. Only a small number of fruit capsules have been found on the various plants at the time of their discoveries. The most recently discovered plant near Mongarlowe had relatively more capsules per branchlet than the other plants. These naturally pollinated capsules contained an average of only 0.6 viable seeds per capsule (Briggs, pers. comm., cited in DECC, 2010). The species has proven to be extremely sensitive to the effects of bagging branchlets as a technique to exclude insect pollinators and hybridisation from cross fertilisation when attempting hand pollination (Briggs, pers. comm., 2014). Hand pollination work without bagging has produced mature fruit and seedlings which appear to be a mix of pure Mongarlowe mallee and hybrids. This progeny awaits results of genetic analysis to determine that pure Mongarlowe mallee plants have been produced, which can then be used to assist recovery (Briggs, pers. comm., 2014). Attempts to date of propagation from tissue culture have failed (Briggs, pers. comm., 2014). The results of the 2001-2 hand pollination trials suggest that for some of the Mongarlowe mallee plants, physical separation and lack of pollen from unrelated individuals of this species may be the major cause of low natural seed production (DECC, 2010). Threats A major threat to the plant that was first found near Mongarlowe is visitation pressures, including the collection of plant material, soil compaction, and other associated habitat damage. Vehicle damage is also a threat to this plant, since a track and recreational vehicles have previously damaged shoots sprouting from the lignotuber. Such visitation and vehicular traffic poses the risk of introduction of soil-borne fungal pathogens such as Phytopthera cinnamomi. Although the exact locations of most of the Mongarlowe mallee plants are currently not widely known, threats associated with increased visitation pressures are likely to occur if visitation is not controlled (DECC, 2010). Eucalyptus recurva (Mongarlowe mallee) Conservation Advice Page 2 of 8 At the Windellama site, the main threat to the two plants has been past habitat loss and degradation associated with clay mining and associated activities that have operated since 1995. Impacts included altered drainage, silt deposition near and around the base of the plants and dust deposition on the foliage (DECC, 2010). The very small number of individuals makes this species highly susceptible to random events (e.g., disease). All individuals occur on private land. Most current owners are supportive of protecting this species; however future owners of the properties may not be as supportive of the protection of the species (NSW OEH, 2012a). How judged by the Committee in relation to the EPBC Act Criteria and Regulations Criterion 1: Reduction in numbers (based on any of A1 – A4) A1. An observed, estimated, inferred or suspected population very severe 90%, severe 70% substantial 50% size reduction over the last 10 years or three generations, whichever is the longer, where the causes of the reduction are clearly reversible AND understood AND ceased, based on (and specifying) any of the following: (a) direct observation (b) an index of abundance appropriate to the taxon (c) a decline in area of occupancy, extent of occurrence and/or quality of habitat (d) actual or potential levels of exploitation (e) the effects of introduced taxa, hybridization, pathogens, pollutants, competitors or parasites. A2. An observed, estimated, inferred or suspected population very severe 80%, severe 50% substantial 30%size reduction over the last 10 years or three generations, whichever is the longer, where the reduction or its causes may not have ceased OR may not be understood OR may not be reversible, based on (and specifying) any of (a) to (e) under A1. A3. A population size reduction very severe 80%, severe 50% substantial 30%, projected or suspected to be met within the next 10 years or three generations, whichever is the longer (up to a maximum of 100 years), based on (and specifying) any of (b) to (e) under A1. A4. An observed, estimated, inferred, projected or suspected population size reduction very severe 80%, severe 50% substantial 30%over any 10 year or three generation period, whichever is longer (up to a maximum of 100 years in the future), where the time period must include both the past and the future, and where the reduction or its causes may not have ceased OR may not be understood OR may not be reversible, based on (and specifying) any of (a) to (e) under A1. Evidence The six mature individuals occurring within four known sites on the Southern Tablelands of NSW were discovered between 1985 and 2010.

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