Eucalyptus Aggregata (Black Gum)

Consultation Document on Listing Eligibility and Conservation Actions

Eucalyptus aggregata (black gum)

You are invited to provide your views about:

1) the eligibility of Eucalyptus aggregata (black gum) for inclusion on the EPBC Act threatened species list; and

2) the necessary conservation actions for the above species.

The views of experts, stakeholders and the general public are welcome. Responses can be provided by any interested person.

Anyone may nominate a native species, ecological community or threatening process for listing under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) or for a transfer of an item already on the list to a new listing category. The Threatened Species Scientific Committee (the Committee) undertakes the assessment of species to determine eligibility for inclusion in the list of threatened species and provides its recommendation to the Australian Government Minister for the Environment.

Draft information for your consideration of the eligibility of this species for listing as endangered starts at page 3 and information associated with potential conservation actions for this species starts at page 11. To assist with the Committee’s assessment, the Committee has identified a series of specific questions on which it seeks your guidance at page 12.

Responses to are to be provided in writing either by email to: [email protected] or by mail to:

The Director Terrestrial Species Conservation Section Wildlife, Heritage and Marine Division Department of the Environment PO Box 787 Canberra ACT 2601

Responses are required to be submitted by 18 November 2014

Contents of this information package Page General background information about listing threatened species 2 Information about this consultation process 2 Draft information about the common name and its eligibility for listing 3 Conservation actions for the species 11 Collective list of questions – your views 12 References cited 14

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General background information about listing threatened species

The Australian Government helps protect species at risk of extinction by listing them as threatened under Part 13 of the EPBC Act. Once listed under the EPBC Act, the species becomes a Matter of National Environmental Significance (MNES) and must be protected from significant impacts through the assessment and approval provisions of the EPBC Act. More information about threatened species is available on the Department’s website at: http://www.environment.gov.au/biodiversity/threatened/index.html.

Public nominations to list threatened species under the EPBC Act are received annually by the Department. In order to determine if a species is eligible for listing as threatened under the EPBC Act, the Threatened Species Scientific Committee (the Committee) undertakes a rigorous scientific assessment of its status to determine if the species is eligible for listing against a set of criteria. These criteria are available on the Department’s website at: http://www.environment.gov.au/biodiversity/threatened/pubs/guidelines-species.pdf.

As part of the assessment process, the Committee consults with the public and stakeholders to obtain specific details about the species, as well as advice on what conservation actions might be appropriate. Information provided through the consultation process is considered by the Committee in its assessment. The Committee provides its advice on the assessment (together with comments received) to the Minister regarding the eligibility of the species for listing under a particular category and what conservation actions might be appropriate. The Minister decides to add, or not to add, the species to the list of threatened species under the EPBC Act. More detailed information about the listing process is at: http://www.environment.gov.au/biodiversity/threatened/nominations.html.

To promote the recovery of listed threatened species and ecological communities, conservation advices and where required, recovery plans are made or adopted in accordance with Part 13 of the EPBC Act. Conservation advices provide guidance at the time of listing on known threats and priority recovery actions that can be undertaken at a local and regional level. Recovery plans describe key threats and identify specific recovery actions that can be undertaken to enable recovery activities to occur within a planned and logical national framework. Information about recovery plans is available on the Department’s website at: http://www.environment.gov.au/biodiversity/threatened/recovery.html.

Information about this consultation process

Responses to this consultation can be provided electronically or in hard copy to the contact addresses provided on Page 1. All responses received will be provided in full to the Committee and then to the Australian Government Minister for the Environment.

In providing comments, please provide references to published data where possible. Should the Committee use the information you provide in formulating its advice, the information will be attributed to you and referenced as a ‘personal communication’ unless you provide references or otherwise attribute this information (please specify if your organisation requires that this information is attributed to your organisation instead of yourself). The final advice by the Committee will be published on the Department’s website following the listing decision by the Minister.

Information provided through consultation may be subject to freedom of information legislation and court processes. It is also important to note that under the EPBC Act, the deliberations and recommendations of the Committee are confidential until the Minister has made a final decision on the nomination, unless otherwise determined by the Minister.

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Eucalyptus aggregata

Black gum

Taxonomy Conventionally accepted as Eucalyptus aggregata Deane & Maiden (Deane & Maiden, 1900).

Description Eucalyptus aggregata, black gum, is a small to medium sized woodland tree that grows 18–20 m tall (Benson and McDougall, 1998; Hill, 2002), although DSE (2004) states that it grows to 25 m. The bark on the trunk and main branches is dark grey to black, deeply fibrous or flaky, which does not shed annually (Hill, 2002). The smaller branches (<8 cm diameter) are covered in smooth white, cream or grey bark which does shed yearly (Brooker et al., 2002; Hill, 2002). The adult leaves are slightly curved and round-ended, approximately 5–12 cm long and 1–2 cm wide. They are a glossy dark green, have the same colour on each surface and contain leaf oils with a distinctive, clove-like odour (Brooker et al., 2002; DSE, 2004; NSW OEH, 2013). Juvenile leaves are narrow or oval-shaped, are arranged opposite each other and are a dull green in colour (Hill, 2002), although they may vary considerably in a single seedlot (Brooker et al., 2002). The buds, flowers and fruits occur in tight clusters of seven on stalks 3–4 mm long. The buds are egg-shaped, 3–5 mm long and 2–3 mm wide (Hill, 2002; NSW OEH, 2013). The flowers are white or cream and are followed by capsules which are cone or cup shaped, 2–4 mm long and 3–5 mm wide (Brooker et al., 2002; Hill, 2002).

Distribution The black gum is endemic to Australia and is found in the ACT, NSW Central and Southern Tablelands and in a small isolated sub-population in Victoria (Brooker et al., 2002; Hill, 2002). It is likely that these sub-populations were connected in a colder palaeoclimate (DSE, 2004). The species occurs mainly in the wetter, cooler and higher parts of the tablelands (NSW OEH, 2013), and is found at altitudes of 800–1200 m and in areas with annual rainfall of 600–900 mm (Benson and McDougall, 1998), although at least one sub-population is known to occur in an area of higher rainfall (~1800 mm per year; NSW Scientific Committee, 2013).

ACT and NSW occurrences:

In the ACT, the species occurs to a very minor extent with the only confirmed extant natural occurrence comprising of two to three trees on the edge of the Kings Highway. These trees make up part of a small stand that extends over the border into NSW (Douglas pers. comm., 2014).

In NSW, the species occurs predominantly in the South Eastern Highlands Bioregion with the most eastern part of the distribution being located just within the Sydney Basin Bioregion (NSW Scientific Committee, 2010). Following Field’s (2008) survey in 2002 / 2003 there were believed to be approximately 110 stands in NSW. Field (2008) considered that around 56 % of these stands consist of scattered trees on grazed privately owned land or linear clusters along road edges. Although a few locations have been recorded since this survey, all are very small and have not expanded the known range or habitat of the species, nor significantly altered the understanding of its abundance or conservation status (Douglas, pers. comm., 2014). The NSW Scientific Committee (2010) considered there to be 130–150 stands when they assessed the species in 2010.

Compilation of available survey data indicates that 6300–8100 mature individuals occur in NSW (NSW Scientific Committee, 2010). Field (2008) estimated in his study that only 9 % of stands Page 3 of 14 Consultation on Eucalyptus aggregata (black gum)

had greater than 200 adult trees and occurred in continuous woodland vegetation habitat likely to represent habitat conditions prior to European land clearing. He also found that 56 % of stands surveyed had fewer than 40 trees. The largest black gum stands in NSW contain around 700–1000 adults, which is small compared to the characteristic largest stands of other Eucalyptus species (Field, 2008). The large stands include Black Springs, Wallerawang, south of Braidwood near the Shoalhaven River, and the Bendoura Travelling Stock Reserve (Field pers. comm., 2014). Some small stands are located in reserve systems, including Tallaganda, Morton, Yanununbeyan, and the Blue Mountains National Parks, and Turallo Nature Reserve (NSW Scientific Committee, 2010). Douglas (2009) states that the occurrences in reserves are ‘poor quality’ and the trees are usually located on the periphery of these reserves.

In 2013 the NSW Scientific Committee determined that the three stands located in the Wingecarribee local government area form a sub-population given their disjunction from other stands of black gum and current estimates of pollen and seed dispersal mean it is unlikely to interact with other black gum stands (NSW Scientific Committee, 2013). This sub-population was determined to be an endangered population in Part 2 of Schedule 1 of the Threatened Species Conservation Act 1995 (NSW Scientific Committee, 2013). The Wingecarribee sub-population was also deemed to be highly fragmented. No research has been conducted to determine whether gene flow is occurring between the remaining stands in NSW. However, given the fragmented nature of the stands across NSW and using the precautionary principle, it is likely that that there are several more sub-populations across NSW.

Victorian occurrences:

The Victorian stands are considered a sub-population given they are located so far from any stands in NSW (DSE, 2004). It has been suggested that this sub-population may not be natural, but instead the result of accidental introduction (Gullan, 2014). However, DSE (2004) do not agree with this view and consider the Victorian sub-population to be natural. All stands are located within four kilometres of the town of Woodend and are considered to be fragmented from one another following extensive clearance (DSE, 2004). Based on surveys in the mid- 1990s, the total number of trees in Victoria was estimated to be 9000–10 000, with approximately 1000 mature trees, 5000 immature trees and 3000 seedlings (DSE, 2004). The distinction between categories is based on tree diameter and height and it is unclear how this relates to the reproductive ability of the plants, as the same document states that the breeding population is considered to be several thousand. A majority of the known stands in Victoria are on private property or public land that is not managed primarily for flora and fauna conservation (Gullan, 2014). One study found that 64 % were on private land, 19 % were on roadsides, 12 % were on council reserves, 2 % were on Western Region Water Authority land and 3 % were managed by the public transport corporation (DSE, 2004). The species is not well represented in the Victorian reserve system (DSE, 2004).

Area of Occurrence and Occupancy: The area of occupancy for black gum is estimated by the Department of the Environment to be 200 km2 in NSW and 20 km2 in Victoria (total 220 km2; Department of the Environment, unpublished data, 2014). In their 2010 assessment of the species the NSW Scientific Committee stated that the extent of occurrence in NSW is 28 000 km2 and that the area of occupancy, based on 2 x 2 km grids, is 520–580 km2 (NSW Scientific Committee, 2010). There are no publically available measures for the Victorian sub-population. Cultural Significance The cultural significance of the black gum is currently unknown.

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Relevant Biology/Ecology Black gum grows on alluvial soils in cold, poorly-drained flats and hollows adjacent to swamps, creeks and small rivers and up adjoining slopes (up to eight metres above waterline) onto Ordovician Sandstones and shales (DSE, 2004; NSW OEH, 2013). It is usually found in open woodland with a grassy understory dominated by river tussock (Poa labillardierei) or kangaroo grass (Themeda triandra) and with few shrubs present (DSE, 2004; NSW OEH, 2013). Black gum is often found with other eucalypts including Snow gum (Eucalyptus. pauciflora), manna or ribbon gum (E. viminalis), candlebark (E. rubida), black sallee (E. stellutata) and swamp gum (E. ovata; Brooker et al., 2002; Field, 2008; NSW OEH, 2013).

Black gum flowers from November through to May (Benson and McDougall, 1998) and DSE (2004) suggest that pollination is likely to occur by a range of insects, birds and mammals. Field et al. (2008) states the pollination system is probably entomophilous (insect mediated) due to floral foraging by a diversity of insect species (including the honeybee Apis mellifera and native bees such as Leioproctus (Colletidae)). Seed is dispersed locally by wind, water and gravity and there is no dormancy phase. Maximum seed fall is thought to be between late summer and early autumn (Benson and McDougall, 1998).

The black gum forms a lignotuber and resprouts from epicormic buds (Benson and McDougall, 1998; Brooker et al., 2002). The effects of fire on the black gum are unknown, but it is not thought to be a significant pressure on the species (DSE, 2004). The species is thought to live for more than 100 years (Benson and McDougall, 1998). The reproductive age and generation length of black gum are not known.

Threats The direct threats facing the black gum include mortality, suppression of gene flow, lack of recruitment and hybridisation. These threats were and are caused by a range of indirect drivers. Climate change is likely to exacerbate some of these threats in the future.

Mortality: The loss of individuals from the population has resulted from land clearing for industry, farming and urban development and is considered to be a past, current and future threat. Much of the black gum habitat in NSW has been cleared or modified for agriculture or the plantation industry (NSW Scientific Committee, 2010). Douglas (2009) states that areas of suitable habitat between remnant populations in NSW no longer support black gum and many show evidence of tree removal and thinning. In Victoria, habitat has been subjected to extensive clearing for development and grazing (DSE, 2004). Although there is a paucity of historical records, the extent of landscape-scale clearing of known and likely habitat for the species would suggest that individual mortality has had an impact on the species. The demand for farming properties to be subdivided for rural-residential use is driving small scale clearing which may pose a considerable threat across much of the black gum’s range (Douglas, 2009; NSW OEH, 2013). Habitat and individuals can also be lost through road maintenance and widening activities, especially as many stands are restricted to road verges. The loss of individuals from the population is likely to remain a significant threat in the future as urbanisation increases, especially considering that 56% of stands occur on privately owned land or along road edges.

Suppression of gene flow:

The clearing of land for industry, farming and urban development has led to the fragmentation of the black gum across its range in both NSW (NSW Scientific Committee, 2010) and in Victoria (DSE, 2004). The Victorian sub-population is considered fragmented (DSE 2004) and the Wingecarribee sub-population is considered both disjunct and severely fragmented

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(NSW Scientific Committee 2013). The NSW Scientific Committee used in its assessment of the Wingecarribee sub-population figures that suggest pollen movement is less than one kilometre and seed dispersal is approximately 300 m (NSW Scientific Committee 2013). Given this information it is considered that the black gum is severely fragmented. This fragmentation may have led to the suppression of gene flow between individuals. In their study of Eucalyptus benthamii, Butcher et al. (2005) found fragmentation and the isolation of trees appears to have resulted in higher levels of selfing and bi-parental inbreeding. Genetic studies however have not been carried out on the black gum to determine the level of gene flow and assess the level of risk that the lack of gene flow as a result of fragmentation poses. Lack of Recruitment: Lack of recruitment is a serious threat particularly as older trees are still being removed from the population by natural events such as wind storms, fire and disease, as well as the result of habitat loss (NSW OEH, 2013). Lack of recruitment is driven by competition from weeds, livestock grazing and inappropriate management activities (NSW Scientific Committee, 2010). Competition from weeds often results from elevated soil fertility as a result of fertilisation of pastures, either from fertilisers or livestock. The moderately fertile and seasonally moist habitat of the black gum is particularly prone to weed invasion and establishment (Douglas, 2009). Almost all understorey vegetation in Victoria in black gum habitat is introduced (DSE, 2004). Weeds that suppress recruitment through competition include blackberry (Rubus spp.), harding grass (Phalaris aquatica), canary grass (Phalaris canariensis), cocksfoot (Dactylis glomerata), willows (Salix spp.) and scotch broom (Cytisus scoparius); (Field, 2008; Douglas, 2009). Grazing by livestock can also decrease levels of recruitment (NSW OEH, 2013). In Victoria, grazed farms have no regeneration below existing black gum (DSE, 2004) and large areas of black gum habitat in NSW are used for agriculture, including grazing (NSW Scientific Committee, 2010). The species regenerates poorly in semi-urban areas due to intensive management activities such as slashing, mowing and herbicide use (DSE, 2004; NSW OEH, 2013). Seedlings on roadsides are at risk from roadside maintenance work. Approximately 90 % of black gum habitat in NSW and 83 % in Victoria occur on private land or roadsides, which are not managed primarily for conservation, and therefore lack of recruitment as a result of land management is a threat (Field, 2008). Genetic hybridisation can also lead to a lack of recruitment.

Hybridisation: Genetic hybridisation is a natural process for Eucalypts, and Black gum is known to naturally hybridise with manna gum and candlebark, which co-occur across much of its range (Griffin et al., 1988). As many as 35 % of seed crops in small remnant of black gum stands in NSW have been found to be hybrids (Field, 2008). However, hybridisation may lead to the extinction of populations, particularly if one taxon is rare. Genetic hybridisation contributes to species decline in two general ways, via demographic swamping and/or introgression, which often work in synergy (Wolf et al., 2001). In some taxa the decline in numbers of genetically pure individuals due to hybridisation has been shown to act very fast (extinction within five generations for some species) and this decline can accelerate due to the feedback effect (Wolf et al., 2001). Field (2008) demonstrated that small, fragmented populations of black gum are at particular risk from hybridisation, particularly where it is out-numbered by the hybridising species. In these areas in NSW he found a particular risk from increased hybrid production and reduced seed production, germination and survivorship of seed cohort (Field, 2008). Based on analyses in 1985 and 1997 DSE (2004) reports a limited amount of hybridisation with swamp gum has occurred in Victoria and that these hybrids were considered rare. The historical significance of hybridisation in black gum is unknown. The current and future level of threat is dependent on the size of the black gum stand, level of fragmentation and presence of hybridising Eucalyptus species. Hybridisation

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is likely to be a threat in small, isolated stands of black gum that are outnumbered by hybridising species, but not in larger stands. Given that the distribution of the black gum is severely fragmented and the majority of black gum stands are small (56% are less than 40 individuals), hybridisation is a particular concern.

Climate change: Climate change is likely to influence many of these threats. As the black gum’s range includes frost hollows and areas with annual rainfall of 600–900 mm, under conditions of increased average temperatures and lower effective rainfall, the viability of populations could be reduced (Hennessy et al., 2004; NSW Scientific Committee, 2010). Climate change is also likely to lead to more frequent, severe and protracted droughts and more frequent and intense fires, which will lead to an increase in mortality. It is also likely to influence the lack of recruitment by intensifying the threat from weeds (Douglas, 2009).

Assessment of available information 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 There is insufficient evidence to estimate the population trend or rate of population change over the past three generations. As there is insufficient evidence to assess against this criterion, it appears the black gum is ineligible for listing under this criterion.

However, the purpose of this consultation draft advice is to elicit additional information to better understand the species’ status. This conclusion should therefore be considered to be tentative at this stage, as it may be changed as a result of responses to this consultation process.

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Criterion 2: Geographic distribution (based on either of B1 or B2) B1. Extent of occurrence estimated to be very restricted <100 km2, restricted <5000 km2 or limited < 20 000 km2 B2. Area of occupancy estimated to be very restricted <10 km2, restricted <500 km2 or limited <2000 km2 AND Geographic distribution is precarious for the survival of the species, (based on at least two of a–c) a. Severely fragmented or known to exist at a limited location. b. Continuing decline, observed, inferred or projected, in any of the following: (i) extent of occurrence (ii) area of occupancy (iii) area, extent and/or quality of habitat (iv) number of locations or subpopulations (v) number of mature individuals. c. Extreme fluctuations in any of the following: (i) extent of occurrence (ii) area of occupancy (iii) number of locations or subpopulations (iv) number of mature individuals

Evidence According to the Department of the Environment the area of occupancy, based on 2 x 2 km grids, is 220 km2 for the species. Therefore the area of occupancy of black gum across its national range is considered restricted (<500 km2).

In Victoria all black gum trees are considered fragmented (DSE, 2004). The NSW Scientific Committee (2013) considers that the Wingecarribee population is disjunct from the rest of the NSW stands and is severely fragmented. Approximately 56 % of the NSW locations consist of scattered trees on heavily grazed privately owned land or as linear clusters on road edges. Therefore the entire distribution of black gum is considered to be severely fragmented.

Given the threats that affect black gum there is a projected continuing decline in the area, extent and quality of its habitat and the number of locations. Given the lack of recruitment into the population at many sites, there is also a projected decline in the number of mature individuals as mature individuals are lost and are not replaced.

Therefore this species fulfils B2 (restricted), (a) and (b) (iii), (iv) and (v).

The data presented above appear to demonstrate that the species is eligible for listing as endangered under this criterion. However, the purpose of this consultation draft advice is to elicit additional information to better understand the species status. This conclusion should therefore be considered to be tentative at this stage, as it may be changed as a result of responses to this consultation process.

Criterion 3: The estimated total number of mature individuals is very low <250, low <2500 or limited<10 000; and either of (A) or (B) is true (A) evidence suggests that the number will continue to decline at a very high (25 % in 3 years or 1 generation (up to 100 years), whichever is longer), high (20 % in 5 years or 2 generations(up to 100 years), whichever is longer) or substantial (10 % in 10 years or 3 generations years), whichever is longer(up to 100) rate; or (B) the number is likely to continue to decline and its geographic distribution is precarious for its survival (based on at least two of a – c): a. Severely fragmented or known to exist at a limited location. b. Continuing decline, observed, inferred or projected, in any of the following:

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(i) extent of occurrence (ii) area of occupancy (iii) area, extent and/or quality of habitat (iv) number of locations or subpopulations (v) number of mature individuals. c. Extreme fluctuations in any of the following: (i) extent of occurrence (ii) area of occupancy (iii) number of locations or subpopulations (iv) number of mature individuals

Evidence Although the number of mature individuals is known to be roughly 6300–8100 in NSW, this information is not clear for the Victorian sub-population. Therefore the total number of mature individuals cannot be determined. As there is insufficient evidence to assess against this criterion, it appears the black gum is ineligible for listing under this criterion.

Criterion 4: Estimated total number of mature individuals: (a) Extremely low < 50 (b) Very low < 250 (c) Low < 1000

Evidence The number of mature individuals is known to be roughly 6300–8100 in NSW. Therefore the total number of mature individuals exceeds the number to make it eligible for the low category (<1000) and it appears the black gum is ineligible for listing under this criterion.

Criterion 5: Probability of extinction in the wild based on quantitative analysis is at least: (a) 50 % in the immediate future, 10 years or three generations (whichever is longer); or (b) 20 % in the near future, 20 year or five generations (whichever is longer); or (c) 10 % in the medium-term future, within 100 years.

Evidence To the best of our knowledge, quantitative analyses on the probability of extinction have not been carried out on any population across its distribution. As there is insufficient evidence to assess against this criterion, it appears the black gum is ineligible for listing under this criterion.

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Recovery Plan A decision about whether there should be a recovery plan for this species has not yet been determined. The purpose of this consultation draft is to elicit additional information to help inform this decision.

Recovery and Impact avoidance guidance

Primary Conservation Objectives 1. Maintain and increase the number and size of wild populations. 2. Maintain and enhance quality existing and potential habitat. 3. Abate identified threats where possible. 4. Investigate options for linking, enhancing or establishing additional populations. 5. Raise awareness of the black gum within the local community. 6. Effectively administer the recovery effort.

Important populations Given its separate location in Victoria, the Woodend population is considered to be an important population. The Wingecarribee local government area population is also considered an important population and has been listed as an endangered population by the NSW Scientific Committee. The larger and more viable stands of black gum in NSW include locations at Black Springs, Wallerawang, south of Braidwood near the Shoalhaven River, and the Bendoura Travelling Stock Reserve (Field pers. comm., 2014).

Important habitat for the survival of the species Black gum grows on alluvial soils in cold, poorly-drained flats and hollows adjacent to swamps, creeks and small rivers and up adjoining slopes (up to eight metres above waterline) onto Ordovician Sandstones and shales. It is usually found in open woodland with a grassy understory dominated by river tussock (Poa labillardierei) or kangaroo grass (Themeda triandra) and with few shrubs present (DSE, 2004; NSW OEH, 2013). Black gum is often found with other eucalypts including Snow gum (E. pauciflora), manna or ribbon gum (E. viminalis), candlebark (E. rubida), black sallee (E. stellutata) and swamp gum (E. ovata; Brooker et al., 2002; Field, 2008; NSW OEH, 2013).

The NSW Office of Environment and Heritage have designated the black gum as a site- managed species under its new Saving our Species program (NSW OEH, 2014). Under this program they have identified four management sites where conservation activities need to take place to ensure the conservation of this species; Coxs River area, Back Creek Travelling Stock Reserve, Bendoura area and one translocation site.

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Information required, research and monitoring priorities 1. Design and implement a monitoring program. 2. More precisely assess population size, distribution, ecological requirements and the relative impacts of threatening processes. 3. Undertake seed germination and/or vegetative propagation trials to determine the requirements for successful establishment. 5. Undertake genetic analyses to: o assess current gene flow (using markers and analyses capable of distinguishing population divergence on an evolutionary timescale, from that which might be due to more recent impacts); and o identify populations with low genetic diversity that might benefit from artificial introduction of genetic material from other populations from which they have relatively recently diverged. 6. Identify optimal fire regimes for regeneration (vegetative regrowth and/or seed germination), and response to other prevailing fire regimes.

Management actions required 1. Avoid the use of fertilisers in or around stands of black gum. 2. Advise landholders of presence, and encourage and support appropriate conservation practices. 3. Manage sites to identify, control and reduce the spread of invasive species. 4. Control access routes to suitably constrain public access to known sites on public land and manage access on private land and other land tenure. 5. If maintenance activities occurs in the area (e.g. roadside maintenance, mowing, spraying,, slashing etc.), ensure land owners/managers use an appropriate management regime that does not detrimentally affect this species and will allow regeneration from seedlings. 6. Manage the populations to maintain genetic diversity. 7. Implement an appropriate fire management regime for protecting key habitat 8. If livestock grazing occurs in the area, ensure land owners/managers use an appropriate management regime and density that does not detrimentally affect this species, will allow regeneration from seedlings outside the growing season and manage total grazing pressure at important sites through exclusion fencing or other barriers. 9. Monitor the progress of recovery, including the effectiveness of management actions and the need to adapt them if necessary. 10. Establish an ex-situ seed collection as an insurance policy and to aid in establishing additional populations if required.

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Collective list of questions – your views

Biological information 1. Can you provide any additional or alternative references, information or estimates on longevity, average life span, reproductive age and generation length? Population size 2. Can you provide a figure or an estimate of the current population size of mature adults of this species (at a locality or at the national extent)? Please provide details of the basis of any figure or estimate, any supporting justification, or other relevant information. If, because of uncertainty, you are unable to provide a single number, you may wish to provide a range. If so, please choose one of the ranges suggested in the table below of possible species numbers, and also choose the level of confidence you have in this estimate: Number of mature individuals is estimated to be in the range of: □ 1 – 250 □ 251 – 2500□ 2501 – 5000 □ 5001 - 10000□ >10 000 Level of your confidence in this estimated decline: □ 0–30% - low level of certainty/ a bit of a guess/ not much information to go on □ 31–50% - more than a guess, some level of supporting evidence □ 51–95% - reasonably certain, information suggests this range □ 95–100% -high level of certainty, information indicates quantity within this range □ 99–100% - very high level of certainty, data are accurate within this range Evidence of population size change 3. Please provide (if known) any additional evidence which shows the population for which you have provided a figure or estimate is stable, increasing or declining. Current Distribution/range/extent of occurrence, area of occupancy 4. Can you provide estimates (or if you disagree with the estimates provided, alternative estimates) of the extent of occurrence and/or area of occupancy for either NSW or Victoria. If, because of uncertainty, you are unable to provide an estimate of extent of occurrence, you may wish to provide an estimated range. If so, please choose one of the ranges suggested in the table below of ranges of extent of occurrence, and also choose the level of confidence you have in this estimated range. Extent of occurrence is estimated to be in the range of: □ <100 km2 □ 100 – 5 000 km2 □ 5 001 – 20 000 km2 □ >20 000 km2 Level of your confidence in this estimated extent of occurrence □ 0–30% - low level of certainty/ a bit of a guess/ not much data to go on □ 31–50% - more than a guess, some level of supporting evidence □ 51–95% - reasonably certain, data suggests this range of decline □ 95–100% -high level of certainty, data indicates a decline within this range □ 99–100% - very high level of certainty, data is accurate within this range

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If, because of uncertainty, you are unable to provide an estimate of area of occupancy, you may wish to provide an estimated range. If so, please choose one of the ranges suggested in the table below of ranges of area of occupancy, and also choose the level of confidence you have in this estimated range. Area of occupancy is estimated to be in the range of: □ <10 km2 □ 11 – 500 km2 □ 501 – 2000 km2 □ >2000 km2 Level of your confidence in this estimated extent of occurrence: □ 0–30% - low level of certainty/ a bit of a guess/ not much data to go on □ 31–50% - more than a guess, some level of supporting evidence □ 51–95% - reasonably certain, data suggests this range of decline □ 95–100% -high level of certainty, data indicates a decline within this range □ 99–100% - very high level of certainty, data is accurate within this range Change in status/rate of change 5. Is the information used to identify the nationally threatened status of the species robust? Have all the underlying assumptions been made explicit? Please provide justification for your response. 6. Can you provide any additional data or information regarding the extent and/or the rate of change at either a locality or the national extent? General 7. Can you provide additional data or information relevant to this assessment? 8. Have you been involved in developing this nomination? Threats 9. Can you provide additional or alternative information on threats, past, current or potential that may adversely affect this species at any stage of its life cycle? 10. Can you provide additional or alternative information on the threat and impact of hybridisation? Are you aware of any potential measures to avoid or mitigate this threat? Management 11. What threats are affecting different sub-populations, how variable are the threats and what is the relative importance of the different sub-populations? Please provide evidence and background information. Cultural significance 12. Can you provide any information regarding the cultural significance of Eucalyptus aggregata (black gum)?

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References cited in the advice • Butcher PA, Skinner AK, Gardiner CA (2005) Increased inbreeding and inter-species gene flow in remnant populations of the rare Eucalyptus benthamii. Conservation genetics 6:213– 226. • Deane H and Maiden JH (1900). Proceedings of the Linnean Society of New South Wales 24: 614. • Department of the Environment (2014). Unpublished data on the area of occupancy for Eucalyptus aggregata, black gum using post 1990s data. Department of the Environment, Canberra, Australia. • Douglas S (2009). Black gum, a nationally threatened tree of upland New South Wales and Victoria. Australian Plant Conservation 17: 18-19. • Douglas S (2014). Personal communication by email 24 July 2014. Ecological Surveys & Planning, Bundanoon, NSW. • DSE (2004). Action Statement - Black Gum Eucalyptus aggregata. Department of Sustainability and Environment, Melbourne, Australia. Available on the web at: http://www.dse.vic.gov.au/__data/assets/pdf_file/0011/103250/084_Black_Gum_1997.pdf • Field DL (2008). The importance of ecological factors in determining the pattern of interspecific hybridisation in fragmented landscapes of Eucalyptus aggregata. PhD thesis, University of Wollongong, NSW. Available on the internet at: http://ro.uow.edu.au/theses/17 • Field DL, Ayre DJ, Whelan RJ, Young AG (2008). Relative frequency of sympatric species influences rates of interspecific hybridization, seed production and seedling performance in the uncommon Eucalyptus aggregata. Journal of Ecology 96: 1198-1210. • Field DL (2014). Personal communication by email 28 July 2014. Institute of Science and Technology, Klosterneuburg, Austria. • Griffin AR, Burgess IP, Wolf L (1988). Patterns of natural and manipulated hybridization in the genus Eucalyptus. Australian Journal of Botany 36: 41-66. • Gullan P (2014). Rare plants of Victoria. Viridians, Melbourne, Australia. Available on the internet at: http://www.viridans.com/RAREPL/longway.htm • Hennessy K, Page C, McInnes K, Jones R, Bathols J, Collins D, Jones R (2004). Climate change in New South Wales. Part 1: Past climate variability and projected changes in average climate. CSIRO Marine and Atmospheric Research, Aspendale, Victoria. • Hill KD (2002). Eucalyptus. In Harden GJ 'Flora of New South Wales Revised Edition Volume 2'. University of NSW Press, Sydney, Australia. • NSW OEH (2013). Black Gum - profile. Office of Environment and Heritage, Sydney. Available on the internet at: http://www.environment.nsw.gov.au/threatenedSpeciesApp/profile.aspx?id=20128 • NSW OEH (2014). Saving Our Species - Black Gum (Eucalyptus aggregata). Office of Environment and Heritage, Sydney, Australia. Available on the internet at: http://www.environment.nsw.gov.au/savingourspeciesapp/project.aspx?ProfileID=20128 • NSW Scientific Committee (2010). Eucalyptus aggregata Deane & Maiden (Black Gum) - vulnerable species. Office of Environment and Heritage, Sydney, Australia. Available on the internet at: http://www.environment.nsw.gov.au/determinations/eucalyptusaggregateFD.htm • NSW Scientific Committee (2013). Eucalyptus aggregata Deane & Maiden (Black Gum) - Endangered population. Office of Environment and Heritage, Sydney, Australia. Available on the internet at: http://www.environment.nsw.gov.au/resources/threatenedspecies/EucaggFDEP.pdf • Wolf DE, Takebayashi N, Rieseberg LH (2001). Predicting the risk of extinction through hybridization. Conservation Biology 15: 1039-1053.

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