Consultation on Species Listing Eligibility and Conservation Actions

Litoria watsoni (Watson’s Tree Frog)

You are invited to provide your views and supporting reasons related to:

1) the eligibility of Litoria watsoni (Watson’s Tree Frog) for inclusion on the EPBC Act threatened species list in the Endangered category; and

2) the necessary conservation actions for the above species.

The purpose of this consultation document is to elicit additional information to better understand the status of the species and help inform on conservation actions and further planning. As such, the below draft assessment should be considered to be tentative as it may change following responses to this consultation process.

Evidence provided by 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.

Responses are to be provided in writing by email to: [email protected]. Please include species scientific name in Subject field. or by mail to:

The Director Marine and Freshwater Species Department of Agriculture, Water and the Environment John Gorton Building, King Edward Terrace GPO Box 858 Canberra ACT 2601

Responses are required to be submitted by 7 May 2021. Contents of this information package Page General background information about listing threatened species 2 Information about this consultation process 3 Consultation questions specific to the assessment 3 Information about the species and its eligibility for listing 5 Conservation actions for the species 13 Listing assessment 26 References cited 18

Department of Agriculture, Water and the Environment 1 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

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/system/files/pages/d72dfd1a-f0d8-4699-8d43- 5d95bbb02428/files/tssc-guidelines-assessing-species-2018.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.

Privacy notice The Department will collect, use, store and disclose the personal information you provide in a manner consistent with the Department’s obligations under the Privacy Act 1988 (Cth) and the Department’s Privacy Policy.

Any personal information that you provide within, or in addition to, your comments in the threatened species assessment process may be used by the Department for the purposes of its functions relating to threatened species assessments, including contacting you if we have any questions about your comments in the future.

Further, the Commonwealth, State and Territory governments have agreed to share threatened species assessment documentation (including comments) to ensure that all States and Territories have access to the same documentation when making a decision on the status of a potentially threatened species. This is also known as the ‘Common Assessment Method’ (CAM). As a result, any personal information that you have provided in connection with your comments may be shared between Commonwealth, State or Territory government entities to assist with their assessment processes.

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The Department’s Privacy Policy contains details about how respondents may access and make corrections to personal information that the Department holds about the respondent, how respondents may make a complaint about a breach of an Australian Privacy Principle, and how the Department will deal with that complaint. A copy of the Department’s Privacy Policy is available at: https://www.awe.gov.au/about/commitment/privacy .

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.

Consultation questions 1. Do you agree with the current taxonomic position of the Australian Faunal Directory for this taxon (as identified in the draft conservation advice)?

2. Can you provide any additional references, information or estimates on longevity, age of maturity, average life span and generation length?

3. Has the survey effort for this taxon been adequate to determine its national distribution and adult population size? Can you provide further details on surveys conducted that are not presented in the document?

4. Do you accept the estimate provided in the nomination for the current population size of the taxon?

5. For any population with which you are familiar, do you agree with the population estimate provided? If not, are you able to provide a plausible estimate based on your own knowledge? If so, please provide in the form: Lower bound (estimated minimum): Upper bound (estimated maximum): Best Estimate: Estimated level of Confidence: %

6. Can you provide any additional data, not contained in the current draft conservation advice, on declines in population numbers over the past or next 10 years or 3 generations, whichever is the longer?

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7. Is the distribution as described in the nomination valid? Can you provide an estimate of the current geographic distribution (extent of occurrence or area of occupancy in km2) of this taxon?

8. Has this geographic distribution declined and if so by how much and over what period of time?

9. Do you agree that the taxon is eligible for inclusion on the threatened species list, in the category listed in the draft conservation advice?

10. Do you agree that the threats listed are correct and that their effects on the taxon are significant?

11. To what degree are the identified threats likely to impact on the taxon in the future?

12. Can you provide additional or alternative information on threats, past, current or potential that may adversely affect this taxon at any stage of its life cycle?

13. In seeking to facilitate the recovery of this taxon, can you provide management advice for the following:

What individuals or organisations are currently, or need to be, involved in planning to abate threats and any other relevant planning issues? What threats are impacting on different populations, how variable are the threats and what is the relative importance of the different populations? Would the development and implementation of a translocation strategy be of benefit? What recovery actions are currently in place, and can you suggest other actions that would help recover the taxon (e.g. Recovery Plan)? Please provide evidence and background information.

14. Can you provide additional data or information relevant to this assessment?

15. Can you advise as to whether this species is of cultural significance to Indigenous Australians?

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Conservation Advice for Litoria watsoni (Watson’s Tree Frog)

This document combines the approved conservation advice and listing assessment for the species. It provides a foundation for conservation action and further planning.

Litoria watsoni © Copyright, Professor Michael Mahony (from University of Newcastle) Conservation status Litoria watsoni (Watson’s Tree Frog) is currently not listed in any category of the threatened species list under the Environment Protection and Biodiversity Conservation Act 1999 (Cwth) (EPBC Act).

Watson’s Tree Frog is being assessed by the Threatened Species Scientific Committee (the Committee). The Committee’s assessment (at Attachment A) finds the species likely to be eligible for listing as Endangered under the EPBC Act.

Watson’s Tree Frog is a recently described species, having been split from L. littlejohni (Littlejohn’s Tree Frog) following a taxonomic revision (Mahony et al. 2020). The two species have a similar appearance, have a comparable biology and ecology, and occupy similar habitat. Almost all available literature pre-dates the taxonomic review, and so has the two species synomysed. Mostly, no differences are noted in the biology or ecology between the northern (Littlejohn’s Tree Frog) species and the southern (Watson’s Tree Frog) species. Therefore, it is assumed the two species are alike in these details, unless otherwise stated.

The main factors that make Watson’s Tree Frog eligible for Endangered listing are its restricted area of occupancy (AOO), suspected ongoing population decline, and the extent of the overlap of its distribution range with burnt areas from the 2019-20 bushfires.

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Species can also be listed as threatened under state and territory legislation. For information on the current listing status of this species under relevant state or territory legislation, see the Species Profile and Threat Database. Species information Taxonomy Conventionally accepted as Litoria watsoni Mahony, Moses, Mahony, Lemckert & Donnellan (2020).

Description Watson’s Tree Frog is a medium-sized frog from the Family Hylidae (“tree frogs”). Females are larger than males, having a snout-to-vent length (SVL) to 64 mm, while males reach 59 mm SVL. The dorsal surface is weakly granular, becoming more granular laterally and on the venter and thighs. Dorsal surfaces of the body and limbs are a light brown, mottled with dark and light flecking of brown and yellow. The sides of the face are lighter still. The ventral surface is granular and white. Distinctive bright orange-red markings are present on the back of the legs and onto the foot, groin, and posterior flanks, and on the upper axial of the forelimbs. The head is longer than it is wide with a rounded snout. The eyes are large and yellowish-gold. The tympanum is circular and visible. A dark stripe extends from the tip of the snout to the eye, continues less intensely behind the eye and over the tympanum, and then onto the flank where it gradually dissipates. The legs are moderate to long. The fingers and toes are long with prominent terminal discs. The fingers are not webbed, while the toes have basal webbing (Mahony et al. 2020).

Watson’s Tree Frog is similar in appearance to Littlejohn’s Tree Frog, with the species physically distinguishable from each other only by small differences in morphometric measurements. The species can more easily be separated by the male’s breeding call, with Watson’s Tree Frog having a lower number of pulses in each note (mean 22.8 compared to 27.8). The call of Watson’s Tree Frog is composed of a series of rapidly repeated notes, lasting for 3–12 seconds, which make a ‘wriiik…wriiik…wriik…wriik’ sound (Mahony et al. 2020).

The tadpole of Watson’s Tree Frog is taken to be the same as described for Littlejohn’s Tree Frog (see conservation status section, above). Tadpoles grows to 88 mm in total length. The body is cylindrical with the abdomen as wide (or slightly wider) as it is deep. The dorsal surface is a dense black or very dark grey and gradually turns dark brown at later stages. The sides of the body and ventral surface are dusky dark grey with a blue sheen and slight copper tints. The snout is rounded. The eyes are copper-gold, laterally positioned, and have a prominent cornea. The dorsal and ventral fins are well arched, reaching a peak at the midpoint of the tail and then tapering to a fine flagellum. Both fins are translucent dusky-grey, and the tail muscle is moderate and dusky-grey (Anstis 2017).

Egg clusters are considered to be the same as described for Littlejohn’s Tree Frog. Clusters consist of up to 70 moderately large eggs. The ovum has a diameter of up 2.4 mm, and the capsule up to 9.2 mm (Anstis 2017).

Distribution Watson’s Tree Frog is distributed from the Budderoo National Park (NP) in south-eastern New South Wales (NSW) to the eastern side of the Snowy River NP in the East Gippsland region of

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Victoria. The species is found at elevations from near sea-level to 1100 m (Mahony et al. 2020). The topography at the northern end of the distribution is recognised as a biogeographic barrier for several taxa, being characterised by steep escarpments and v-shaped valleys (Bryant & Krosch 2016; Mahony et al. 2020) and marks the geographic delineation between Littlejohn’s Tree Frog and Watson’s Tree Frog.

The distribution is patchy throughout the species’ range, and there are very few records. Most records are from the Shoalhaven River catchment at the northern extent of the distribution (Barren Grounds Nature Reserve on the Budderoo Plateau and Parma Creek Nature Reserve) (Mahony et al. 2020). South of this region, Watson’s Tree Frog has been infrequently recorded (ALA 2020; DPIE 2020a), and a notable range disjunction occurs between the latitude of the Australian Capital Territory (ACT) and the NSW-Victorian border, from where the species has never been recorded. In Victoria, there are very few recent species records. Watson’s Tree Frog was rediscovered in the state in 2015, having been absent from the biological record since 1996 (WU 2017; DELWP 2020a). Subsequently, extensive searches (2015-20) have located the species at 31 sites (waterbodies separated by at least 100 m), all within the East Gippsland region (Gillespie et al. 2016; WU 2017, 2020; DELWP 2020). The specific details of the localities in Victoria are not disclosed in this document to minimise the risk of disturbance.

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Map 1 Modelled distribution of Watson’s Tree Frog

Source: Base map Geoscience Australia; species distribution data Species of National Environmental Significance database.

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Relevant biology and ecology The biology and ecology of Littlejohn’s Tree Frog and (by extension) Watson’s Tree Frog are not fully understood (Gillespie 2016; Hunter et al. 2018). The monitoring effort for these species is ranked amongst the lowest of all Australian frog species (Scheele & Gillespie 2018), and further studies are required to provide information on aspects of the species’ population demographics and dynamics and the species’ habitat requirements.

Habitat Watson’s Tree Frog is a forest-dependent species, being recorded from a range of natural forest vegetation types at low to high elevations. The species is found in wet and dry forest, woodland, bushland, and heathland (Lemckert et al. 2005; DEWHA 2008; Lemckert 2009, 2010; Lemckert & Mahony 2018; Mahony et al. 2020). However, the species prefers moister areas, with most records from wet forest, followed by damp forest, and warm temperate rainforest (Lemckert 2010; Gillespie et al. 2016). In Victoria, tall moist forest habitats are usually nearby breeding sites, suggesting that these may be important refuges during drought or fire. The species has never been recorded from areas of cleared native forest, such as farmland or forest plantations (Gillespie et al. 2016).

The most important variable determining the presence of Watson’s Tree Frog is long lasting pools that allow tadpoles to reach metamorphosis (Lemckert 2009, 2010). Surrounding habitat consists of leaf litter and low native vegetation on mostly sandy soils (Lemckert et al. 2005; Lemckert 2009; 2010; OEH 2017a; Mahony et al. 2020). Within this habitat, Watson’s Tree Frog is mostly found in moist, sunny, and relatively flat areas (Lemckert 2009, 2010; Lemckert & Mahony 2018) but has also been found sheltering under rocks on high exposed ridges during summer (DPIE 2000). Non-breeding habitat is unknown (Gillespie et al. 2016).

Breeding Watson’s Tree Frog is a generalist pond-breeder, similar to other species in the L. ewingii species complex (a group of phylogenetically related frog species that includes Littlejohn’s Tree Frog). Most breeding sites are along lentic water bodies, including ephemeral and permanent ponds, both natural and man-made (Lemckert 2009; DEPI 2014; Gillespie et al. 2016; Mahony et al. 2020). When breeding along streams, they are characterised by being potholed or with lateral rocks bars creating pools that are either completely isolated from surrounding water bodies or larger connected pools (Mahony et al. 2020). Other species in the L. ewingii complex spend the majority of their time dispersed in the surrounding habitat, visiting ponds only during suitable breeding conditions. However, it is unknown how far from breeding sites Watson’s Tree Frog disperses or the wider range of habitats that it uses.

Males call from the branches up to 1.5 m above breeding sites or from deep within large clumps of ferns at most times of the year (Lemckert 2009; Gillespie et al. 2016; Mahony et al. 2020). Peak calling periods for Littlejohn’s Tree Frog and (by extension) Watson’s Tree Frog has been identified as September and February (White et al. 1994; Daly & Craven 2007; Anstis 2017). However, no peak calling period is noted in the Victorian distribution. Calling is triggered by heavy rain, or whenever sufficient run-off water is available (White et al. 1994; Lemckert 2010; OEH 2017a). Choruses are small with most sites containing no more than four males (Lemckert 2004 cited in Daly & Craven 2007; DEWHA 2008).

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Watson’s Tree Frog has a relatively low fecundity compared to other similar-sized frogs (Gould et al. 2020). Females lays up to 70 eggs in a clutch, which are attached to submerged twigs, stems, or overhanging branches at the banks of pond or stream that receive extended exposure to sunlight. A female may lay a clutch in several batches (White et al. 1994; DPIE 2000; Daly & Craven 2007; DEPI 2014; Anstis 2017; OEH 2017a).

After hatching, tadpoles often congregate near the surface of still ponds or pools and are capable of very agile swimming if disturbed. Large aggregations have been observed schooling. Tadpoles feed on vegetation, sediment, and surface matter but also feed on the egg jelly capsules of other frog species as well as their own (Daly & Craven 2007; Anstis 2017). Metamorphosis has been recorded in captivity after 109 days of development, but under natural conditions this period is likely to be shorter (Anstis 2017).

Behaviour Generally, male pond-breeding frogs have been recorded to stay within 10 m of the perimeter of ponds during the breeding season, and radio-tracking of female Littlejohn’s Tree Frogs and (by extension) Watson’s Tree Frogs showed they mostly remain within 20 m of breeding sites during reproductive activity (Lemckert et al. 2011). However, the distance Watson’s Tree Frog will move to reach breeding habitat is unknown. The species has rarely been found when not breeding, or away from breeding locations. This suggests that it resides only temporarily in the vicinity of breeding sites and otherwise disperses into the surrounding forest (Gillespie et al. 2016).

Habitat critical to the survival There is insufficient data to define habitat critical to the survival of Watson’s Tree Frog. The species has poorly defined habitat preferences, being identified as a generalist pond-breeder with non-breeding habitat unknown, and is reliably found at just a few locations. Given this lack of known site affiliation, it is not possible to identify the bounds of habitat critical to the survival with the necessary specificity to provide additional protection under the EPBC Act.

No Critical Habitat as defined under section 207A of the EPBC Act has been identified or included in the Register of Critical Habitat.

Threats Watson’s Tree Frog is a forest dependent species and is likely to be adversely affected by disturbance and loss of habitat (Gardner et al. 2007; Gillespie et al. 2016). Across the distribution range, this has occurred through climate change (including increased severity and frequency of bushfires and drought), introduced species (including livestock and feral deer), and visitors to National Parks. Additionally, habitat outside of protected areas (roughly 50 percent of the distribution) has been impacted by activities conducted by primary industries (agriculture, forestry, and mining) and urban development. Also, the amphibian chytrid fungus (Batrachochytrium dendrobatidis (Bd)) is widespread along the east-coast of Australia (CoA 2016) and is implicated in the mass die-off and extinction of frog species (Berger et al. 2016; Skerratt et al. 2016; DoEE 2016). Both loss of habitat and disease can result in the fragmentation of the population, with small, isolated subpopulations being more vulnerable to stochastic events such as drought.

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Table 1 Threats impacting Watson’s Tree Frog

Threat Status and severity Evidence

Habitat loss and fragmentation

Vegetation Status: current Disturbance to forest habitat can result in the mortality of clearance/habitat individual frogs and the loss of suitable habitat for shelter, Confidence: known fragmentation foraging, and dispersal. Consequence: severe Approximately half of the Watson’s Tree Frog distribution is Trend: increasing outside of reserves (National Parks and Wildlife Service estates) (OEH 2017a; Mahony et al. 2020) and may be subject Extent: across part of the to disturbance from primary industries and urban range development.

Much of the known habitat in Victoria has been subject to logging (Gillespie et al. 2016). Management measures, such as pre-development surveys to designate buffer zones, offer limited protection as Watson’s Tree Frog is difficult to detect, especially outside of the breeding season (Gillespie et al. 2016; Hunter et al. 2018).

Alteration to Status: current Primary industries can impact breeding habitat by altering groundwater hydrological regimes within catchments. Longwall coal Confidence: known hydrology mining can alter local topography (through subsidence), Consequence: severe which may reduce surface runoff following rainfall events. This physical change to the landscape, together with water Trend: unknown capture by dams and ground water extraction for agriculture Extent: across part of the and forestry, can reduce the area and duration of ponding range and thereby reduce the availability of breeding sites. In addition, water pollution and increased sediment loads from run-off from primary industries (as well as urban development) can impact egg and tadpole development (deMaynadier & Hunter 1995; Welsh & Ollivier 1998).

Climate change

Increased severity Status: current Climate change is expected to cause a pronounced increase in and frequency of extinction risk for frog species over the coming century Confidence: known heatwaves and (Hagger et al. 2013; Pearson et al. 2014). Climate projections change to Consequence: severe for south-eastern Australia include reduced rainfall, precipitation increased average temperatures, and more frequent Trend: increasing patterns droughts. These conditions will increase the scale, frequency, Extent: across the entire and intensity of bushfires (CSIRO 2007; Hobday & Lough range 2011; CSIRO & Bureau of Meteorology 2015). Climate change is expected to impact frog recruitment by reducing the area and duration of ponding and altering the seasonality of breeding sites (Lemckert and Penman 2012; DEPI 2014; Lowe et al. 2015).

Increased Status: current Localised extinction of frogs has been observed through intensity/frequency bushfire events. Frogs have little defence against fire. They Confidence: known of bushfire are unable to flee and have a low tolerance of extreme Consequence: severe temperatures and desiccation (Gillespie et al. 2016). As a non-burrowing species, Watson’s Tree Frog faces a greater Trend: increasing threat from fire, through both direct contact as well as a Extent: across the entire reduction in leaf-litter for foraging and shelter. range

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Threat Status and severity Evidence Bushfires can adversely affect pond breeding habitat, increasing water temperature, altering water chemistry (Lyon & O’Connor 2008), and creating sediment/ash runoff ‘slugs’ that can form in waterways following rainfall (Lyon & O’Connor 2008; Alexandra & Finlayson 2020). These slugs can fill in crevices in pond substrates, reducing the availability of refugia for tadpoles (Welsh & Ollivier 1998), and promote toxic algal blooms (Alexandra & Finlayson 2020) that can deoxygenate the water and cause egg and tadpole death. Sediment slugs can persist for a significant period of time and reach aquatic ecosystems up to 80 km downstream of burnt areas, greatly increasing the impact on pond dependent species outside of the immediate burnt area (Lyon & O’Connor 2008; Alexandra & Finlayson 2020).

Recent significant fire events have extensively overlapped with the Watson’s Tree Frog distribution range. In 2006-07, fires burnt over 1 million ha in the northeast of Victoria, including the Gippsland region (FFM 2020), in 2012-13, bushfires again burnt large areas of the species’ Victorian distribution (Gillespie et al. 2016), and in 2019-20, catastrophic bushfire conditions culminated in fires that overlapped with roughly 85 % of the species distribution range. This sort of event is increasingly likely to reoccur as a result of climate change.

Disease

Chytridiomycosis Status: current Chytridiomycosis is an infectious disease caused by the caused by chytrid amphibian chytrid fungal pathogen Batrachochytrium Confidence: inferred fungus dendrobatidis (Bd). Infected subpopulations exhibit diverse Consequence: moderate susceptibility to Bd. Some species do not show any apparent symptoms while others are extremely vulnerable, resulting in Trend: unknown mass die-off and extinction (DOEE 2016). Mortality Extent: across the entire associated with Bd erodes the capacity of the population to range sustain loss of recruitment associated with drought and reduces resilience to climate change (Scheele et al. 2016).

Skerratt et al. (2016) identified Littlejohn’s Tree Frog and (by extension) Watson’s Tree Frog as being at a moderate risk of extinction from chytridiomycosis, with the species highly likely to have already been exposed to Bd (Gillespie et al. 2016). Mahony et al. (2020) identified Bd as the likely cause of the observed population decline during the 1990s.

Bd has not been eradicated in wild frog populations, and there is no evidence that Bd has disappeared from any known location in eastern Australia (Voyles et al. 2009). Some amphibian species are reasonably tolerant, acting as a natural reservoir, spreading the pathogen, which persists even at low host densities (Brannelly et al. 2018).

Invasive species

Introduced fauna Status: current Livestock and feral deer occur in the distribution range of Watson’s Tree Frog. By grazing on native vegetation, these Confidence: known introduced species may alter the floristics of the habitat and

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Threat Status and severity Evidence Consequence: moderate encourage weeds to establish. Also, trampling at the edges of ponds and streams contributes to erosion, thereby degrading Trend: unknown water quality and increasing sediment load (DSEWPC 2011). Extent: across the entire range The extent of predation by the feral cat (Felis catus) and the European red fox (Vulpes vulpes) on Watson’s Tree Frog is unknown. However, a study by Woinarski et al. (2020) indicated that nearly 100 million frogs are killed annually in Australia by the feral cat. Also, recent bushfires may have led to increased predation of Watson’s Tree Frog. In the aftermath of a fire, survivors are far easier to catch by predators (Leahy et al. 2015; McGregor et al. 2015), and the number of predators attracted to the area (Hradsky et al. 2017) and predator activity (Leahy et al. 2015) increase where habitat has been modified through frequent or intense burning.

Predation of eggs and tadpoles by introduced fish species (such as the Plague Minnow (Gambusia holbrooki)) and Cherax destructor (Freshwater Yabby) may also impact on Watson’s Tree Frog recruitment (Daly & Craven 2007). Recreational activity

Visitors to National Status: current With increased tourism to National Parks and State Forests, Parks there is a greater number of vehicles travelling through the Confidence: suspected distribution range of Watson’s Tree Frog. This increases the Consequence: moderate chance of frog road-kill.

Trend: unknown Increased use of waterways by National Parks visitors can impact on frog recruitment. Walking tracks that cross Extent: across part of its streams or are adjacent to ponds where frogs lay eggs are at range risk of trampling, increased erosion and direct mortality of eggs and tadpoles.

Impacts from visitors will vary between National Parks. Some National Parks (Dharawal and parts of Budderoo) are now closed for vehicle access, while others are very large (Morton) and have large areas unlikely to be disturbed.

Status—identify the temporal nature of the threat; Confidence—identify the extent to which we have confidence about the impact of the threat on the species; Consequence—identify the severity of the threat; Trend—identify the extent to which it will continue to operate on the species; Extent—identify its spatial content in terms of the range of the species.

Conservation and recovery actions Primary conservation outcome

2019-20 bushfire response • Conduct on-ground surveys to establish extent of population response to the 2019-20 bushfires and to provide a baseline for ongoing monitoring. The design of these surveys should reflect considerations in Southwell (2020).

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• In the aftermath of the bushfires, manage unburnt areas within or adjacent to recently burnt areas from further fire, in order to provide refuge sites, as well as unburnt areas that are not adjacent to burnt areas.

• Control introduced predators to support the recovery of populations affected by fires or populations near areas that have been affected by fire.

• Control introduced herbivores to support the regeneration of forest habitat at some localised sites.

• Remove weeds and conduct habitat restoration works to support the regeneration of forest habitat at some localised sites. Note: this should be undertaken by cutting and pasting/painting methods as herbicide formulations can be toxic to frogs and tadpoles, particularly if they contain glyphosate and surfactants (Mann et al. 2003).

• Establish the impact of fire retardants used to fight bushfires on frog populations. Conservation and management priorities Habitat loss disturbance and modifications • Undertake surveys to determine the current distribution and spatial, temporal, and demographic characteristics of the suspected decline in population size.

• Identify the species’ breeding and non-breeding habitat requirements, and evaluate factors influencing the quality and availability of suitable habitat across its distribution.

• Identify key sites and protect and maintain a sufficient amount of high quality habitat to ensure the species viability.

• Identify and conserve landscape characteristics that facilitate movement between subpopulations.

• Minimise human disturbance to Watson’s Tree Frog and its habitat. Designate protection zones around all known site locations to ensure habitat is not fragmented by roads, timber harvesting, or clearing of freehold land. Activities permitted in protection zones should be dictated by further monitoring and research into the effects of disturbance on Watson’s Tree Frog.

• Assess the effectiveness of current forestry management practices in ameliorating disturbance to the habitat of Watson’s Tree Frog, and revise management practices if necessary. Given the suspected impacts of logging on the species, stringent protection measures should be adopted.

• Investigate options for enhancing the resilience of the species’ current habitat to climate change and options for providing new habitat that would be suitable for the species under climate change scenarios.

• Encourage landholders to enter land management agreements, particularly in-perpetuity covenants, that promote the protection and maintenance of key distribution areas. Invasive species (including threats from grazing, trampling, predation) • In areas burnt by the 2019-20 bushfires, control introduced species (including predators, herbivores, and weeds) to support population recovery.

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• Prevent the introduction and reduce populations of non-native fish and the Freshwater Yabby in streams where these species occur. Disease • Investigate measures for minimising the impact of Bd on Watson’s Tree Frog subpopulations. In particular:

o Establish the susceptibility of Watson’s Tree Frog to Bd and whether the species has developed an immune response, or the strain is reduced in virulence.

o Conduct research into mechanisms of frogs’ resistance to Bd, with any identified mechanisms considered to be used in selective breeding methods to produce resistant frogs for release.

o Investigate the availability of Bd refuge sites, either within or outside of the natural known range of the species.

• Minimise the spread of Bd.

o implement suitable hygiene protocols (Murray et al. 2011) to protect priority populations as described in the threat abatement plan for infection of amphibians with chytrid fungus resulting in chytridiomycosis (DoEE 2016).

o Provide disease identification and prevention protocols (methods of handling, diagnostic keys, etc.) to researchers and land managers for use in the field. Breeding and other ex situ recovery action • Investigate options for reintroductions if subpopulations continue to become fragmented and isolated, especially if declines continue within isolated subpopulations. Any translocation program should be done via captive reared animals where possible. Where not deemed a threat to survival, monitor the movement of individuals via mark-recapture methods, radio tracking, or genetic methods.

• Assist wild breeding by creating suitable habitat. Watson’s Tree Frog will readily breed at artificial sites. Monitor the effectiveness and adapt as necessary. Stakeholder engagement/community engagement • Educate landowners and managers of the importance of maintaining riparian and lentic habitat and the integration of habitat protection into land management regulations.

• Provide input into the various impact assessment and planning processes on measures to protect Watson’s Tree Frog and its habitat. These include water resource plans, park management plans, and environmental impact assessments.

• Engage interested nature conservation, land management, and land holder groups in conservation management activities and citizen science projects, such as non-invasive monitoring through the FrogID project. Activities need to be carefully managed to prevent disturbance to frogs and participants should be made aware of the need to follow correct field practices and hygiene protocols to mitigate the risks of trampling and disease transmission. If necessary, use workshops to aid stakeholders in developing the skills and knowledge required to manage threats to this species while undertaking these activities.

Threatened Species Scientific Committee 15 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

• Provide advice to private land holders and community groups on how to protect and restore habitat and to ameliorate the impacts of introduced species.

• Liaise with mining companies in habitat areas to avoid impacts of mining on streams and swamps. Avoid diversion of surface water to the sub-surface so that hydrological regimes are maintained and water flows and water quality around the upper reaches of streams and swamps are protected.

• Work closely with trail bike riding associations to raise awareness about the potential damage to habitat from bikes in particularly sensitive locations. Survey and monitoring priorities • Monitor the species to detect any change in population and to understand how different subpopulations are responding in different environmental and management settings and in response to various threats or ecological loads. Ensure that surveys are conducted when detection is most likely (peak calling period between September and February, following rainfall). In addition, searches for tadpoles can be conducted outside this period, as tadpoles can be found during a large proportion of the year, or eDNA could be used to search for presence or absence of individuals.

• Assess the population size, distribution and ecological requirements (breeding and non-breeding habitat requirements) of Watson’s Tree Frog using modelling and analytical methods.

• Survey sites within the known distribution range of the species where the environment is considered likely to be suitable for the species to identify whether populations exist that are previously unknown. Information and research priorities

• Conduct research at the southern border of the Sydney Basin Bioregion and the northern border of the South East Corner Bioregion to better understand the distribution of Watson’s Tree Frog and Littlejohn’s Tree Frog to determine whether they are sympatric in the zone where these two bioregions meet.

• Identify all potential threatening processes that may have affected the species distribution and abundance, then evaluate their relative contribution to the decline and impediment to recovery. In particular:

o Assess the effects of fire on survival and reproduction, including: . The impact of altered environmental attributes, such as sediment loads, stream hydrological regimes, and riparian vegetation structure and composition. . The species’ long-term response to major fire events or altered fire regimes, through identifying those parts of its range that are most vulnerable, or conversely, where there are opportunities to enhance refuges from fire.

o Improve understanding of the extent and impact of infection by Bd on Watson’s Tree Frog to better inform how to apply existing or new management actions relevant to the recovery.

Threatened Species Scientific Committee 16 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

o Understand the influence of climate change on the long-term survival prospects of the species, due to altered temperatures, rainfall patterns, bushfires, environmental stressors and diseases, through maintaining robust population and environmental monitoring. Links to relevant implementation documents DAWE (Department of Agriculture, Water and the Environment) (2020). Wildlife and threatened species bushfire recovery research and resources. Viewed: 28 February 2020 Available at: https://www.environment.gov.au/biodiversity/bushfire-recovery/research-and-resources

DEPI (Victorian Department of Environment and Primary Industries) (2014). Action statement large brown tree frog Litoria littlejohni Flora and Fauna Guarantee Act 1988. Viewed: 19 February 2020 Available: https://www.environment.vic.gov.au/conserving-threatened- species/flora-and-fauna-guarantee-act-1988/action-statements

DEWHA (Department of the Environment, Water, Heritage and Arts) (2008). Approved Conservation Advice for Litoria littlejohni (Littlejohn’s Tree Frog). Viewed: 18 February 2020 Available at: http://www.environment.gov.au/biodiversity/threatened/species/pubs/64733- conservation-advice.pdf

DoEE (Commonwealth Department of the Environment & Energy) (2016). Threat abatement plan for infection of amphibians with chytrid fungus resulting in chytridiomycosis, Commonwealth of Australia 2016. Viewed: 25 October 2020 Available at: http://www.environment.gov.au/biodiversity/threatened/publications/tap/infection- amphibians-chytrid-fungus-resulting-chytridiomycosis-2016

DoEE (Commonwealth Department of the Environment & Energy) (2017). Threat abatement plan for predation, habitat degradation, competition and disease transmission by feral pigs (Sus scrofa). Commonwealth of Australia. Viewed 25 October 2020. Available from: http://www.environment.gov.au/system/files/resources/b022ba00-ceb9-4d0b-9b9a- 54f9700e7ec9/files/tap-feral-pigs-2017.pdf

OEH (NSW Office of Environment and Heritage) (2017a). Littlejohn’s Tree Frog – profile. Viewed: 18 February 2020 Available at: https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10488

Threatened Species Scientific Committee 17 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Conservation Advice and Listing Assessment references References cited in the advice

Alexandra J & Finlayson CM (2020). Floods after bushfires: rapid responses for reducing impacts of sediment, ash, and nutrient slugs. Australasian Journal of Water Resources 19(1), 1-3.

Anstis M (2017). Litoria littlejohni in Tadpoles and frogs of Australia, 2nd edition. New Holland Publishers, Australia. pp 237-239.

Barker J, Grigg GC, & Tyler MJ (1995). A Field Guide to Australian Frogs. Chipping Norton, NSW: Surrey Beatty & Sons.

Berger L, Roberts AA, Voyles J, Longcore JE, Murray KA & Skerratt LF (2016). History and recent progress on chytridiomycosis in amphibians. Fungal Ecology 19(2016), 89-99.

Brannelly LA, Webb RJ, Hunter DA, Clemann N, Howard K, Skerratt LF, Berger L, & Scheele BC (2018). Non‐declining amphibians can be important reservoir hosts for amphibian chytrid fungus. Animal Conservation 21(2), 91-101.

Bryant LM & Krosch MN (2016). Lines in the land: a review of evidence for eastern Australia’s major biogeographical barriers to closed forest taxa. Biological Journal of the Linnean Society 119, 238–264.

Cashins SD, Grogan LF, McFadden M, Harlow PS, Berger L & Skerratt LF (2013). Prior Infection does not improve survival against the amphibian disease chytridiomycosis. Public Library of Science 8(2), 1-7.

Clemann N, Hunter D, Scroggie M, Pietsch R, & Hollis G (2009). Vanishing frogs: prevalence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) in populations of key frog species in the Australian Alps. Department of Sustainability and Environment, Heidelberg, Victoria. pp 1-41.

Daly G & Craven P (2007). Monitoring populations of Heath Frog Litoria littlejohni in the Shoalhaven region on the south coast of NSW. Australian Zoologist 34(2), 165-172. deMaynadier PG & Hunter MLJ (1995). The relationship between forest management and amphibian ecology: a review of the North American literature. Environmental Review 3, 230- 261.

Gardner TA, Barlow J & Peres CA (2007) Paradox, presumption and pitfalls in conservation biology: The importance of habitat change for amphibians and reptiles. Biological Conservation 138, 166-179.

Threatened Species Scientific Committee 18 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Gillespie GR (2010). Population age structure of the spotted tree frog Litoria spenceri: insights into population declines. Wildlife Research 37, 19-26.

Gillespie GR (2011). Life history variation in the spotted tree frog Litoria spenceri (Anura: Hylidae) from South Eastern Australia. Herpetologica 67,10-22.

Gillespie GR & Hines H (1999). Status of temperate riverine frogs in southeastern Australia in A Campbell (ed) Declines and disappearance of Australian frogs. Environment Australia, Canberra. pp 109-130

Gillespie GR, Hunter D, Berger L & Marantelli G (2015). Rapid decline and extinction of a montane frog population in southern Australia follows detection of the amphibian pathogen Batrachochytrium dendrobatidis. Animal Conservation 18, 295-302.

Gillespie GR, Hunter D, Hollis G, Scheele BC & West M (2018). A tale of threatened frogs: demonstrating the value of long-term monitoring in S Legge, N Robinson, B Scheele, D Lindenmayer, D Southwell & B Wintle (eds) Monitoring threatened species and ecological communities. CSIRO Publishing, Clayton South Victoria. pp 165-177.

Gillespie GR, McNabb E, Gaborov R (2016). The biology and status of the large brown tree frog Litoria littlejohni in Victoria. Victorian Naturalist 133, 128-138.

Gould J, Beranek C, Valdez J, & Mahony M (2020). Quality versus quantity: The balance between egg and clutch size among Australian amphibians is related to life history and environmental conditions. BioRxiv, 1-35. Available at: https://www.biorxiv.org/content/10.1101/2020.03.15.992495v1.abstract

Hagger V, Fisher D, Schmidt S & Blomberg S (2013). Assessing the vulnerability of an assemblage of subtropical rainforest vertebrate species to climate change in south-east Queensland. Austral Ecology 38, 464-475. Hradsky BA, Mildwaters C, Ritchie EG, Christie F & Di Stefano J (2017) Responses of invasive predators and native prey to a prescribed forest fire. Journal of Mammalogy 98, 835-847.

Hero JM, Richards S, Alford R, Allison A, Bishop P, Gunther R, Iskandar D, Kraus F, Lemckert F, Menzies J, Roberts D & Tyler M (2008). Amphibians of the Australasian realm in S Stuart, M Hoffmann, J Chanson, N Cox, R Berridge, P Ramani & B Young (eds) Threatened amphibians of the World. Lynx Edicions, Barcelona, Spain. pp. 65-70

Hobday AJ & Lough JM (2011). Projected climate change in Australian marine and freshwater environments. Marine and Freshwater Research 62, 1000-1014.

Threatened Species Scientific Committee 19 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Hollis G (2004). Ecology and conservation biology of the Baw Baw Frog Philoria frosti (Anura: Myobatrachidae): distribution, abundance, autoecology and demography. Department of Zoology, University of Melbourne.

Hunter D, Clemann N, Coote D, Gillespie G, Hollis G, Scheele B, Philips A & West M (2018). Frog declines and associated management response in south-eastern mainland Australia and Tasmania in H Heatwole & JJL Rowley (eds). Status of conservation and decline of amphibians Australia, New Zealand, and Pacific Islands. CSIRO Publishing, Clayton South, Victoria. p 44.

Leahy L, Legge SM, Tuft K, McGregor HW, Barmuta LA, Jones ME, & Johnson CN (2015). Amplified predation after fire suppresses rodent populations in Australia’s tropical savannas. Wildlife Research 42, 705-716.

Lemckert F (2009). Habitat requirements and management of the threatened heath frog, Litoria littlejohni in Managing pond breeding frogs in the forests of eastern NSW. PhD thesis, School of Environmental and Life Sciences, University of Newcastle, Australia. pp. 162-185.

Lemckert F (2010). Habitat relationships and presence of the threatened heath frog Litoria littlejohni (Anura: Hylidae) in central New South Wales, Australia. Endangered Species Research 11, 271-278.

Lemckert F (2011). Managing pond-breeding anurans in the selectively harvested forests of coastal New South Wales, Australia. Forest Ecology and Management 262, 1199-1204.

Lemckert F, Haywood A, Brassil T, & Mahony M (2005). Correlations between frogs and pond attributes in central New South Wales, Australia: What makes a good pond? Applied Herpetology 3, 67-81.

Lemckert F & Mahony M (2018). The status of decline and conservation of frogs in temperate coastal south-eastern Australia in H Heatwole & JJL Rowley (eds). Status of conservation and decline of amphibians Australia, New Zealand, and Pacific Islands. CSIRO Publishing, Clayton South, Victoria. p 63-64.

Lowe K, Castley JG, Hero J-M (2015). Resilience to climate change: complex relationships among wetland hydroperiod, larval amphibians and aquatic predators in temporary wetlands. Marine and Freshwater Research 66, 886-899.

Lyon JP & O’Connor JP (2008). Smoke-related on sediment the water: slug? Can Australriverine Ecology fish populations 33, 794–806. recover Mahonyfollowing M, Moses a catastrophic B, Mahony fire SV, Lemckert FL, & Donnellan S (2020). A new species of frog in the Litoria ewingii species group (Anura: Pelodryadidae) from south-eastern Australia. Zootaxa 4858(2), 201-230.

Threatened Species Scientific Committee 20 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Mann RM, Bidwell JR & Tyler MJ (2003). Toxicity of herbicide formulations to frogs and the implications for product registration: a case study from Western Australia. Applied Herpetology 1, 13–22.

McCall C, Gaborov R, Fyfe G, Reside J, & Brightman H (2018). Large Brown Tree Frog – Litoria littlejohni surveys 2017. Wildlife Unlimited Ltd, Bairnsdale, Victoria. McGregor H, Legge S, Jones ME, & Johnson CN (2015) feral cats are better killers in open habitats, revealed by animal-borne video. PLoS ONE 10, e0133915.

Morrison C, Hero JM, & Browning J (2004). Altitudinal variation in the age at maturity, longevity, and reproductive lifespan of anurans in subtropical Queensland. Herpetologica 60(1), 34-44.

Osborne W, Hunter D, & Hollis G (1999). Population declines and range contraction in Australian alpine frogs. In: A. Campbell (ed.) Declines and Disappearances of Australian Frogs. Environment Australia, Canberra. pp 145-157.

Payne A (2014). Observations on the calling behaviour of the Jervis Bay Tree Frog Litoria jervisiensis. Zoologist 37(2), 263-266.

Pearson RG, Stanton JC, Shoemaker KT, Aiello-Lammens ME, Ersts PJ, Horning N, Fordham DA, Raxworthy CJ, Ryu HY, McNees J & Akçakaya HR (2014). Life history and spatial traits predict extinction risk due to climate change. Nature Climate Change 4. pp 217–221.

Penman TD, Lemckert FL & Mahony MJ (2006). A preliminary investigation into the potential impacts of fire on a forest dependent burrowing frog species. Pacific Conservation Biology 12, 78-83.

Scheele BC & Gillespie GR (2018). The extent and adequacy of monitoring for Australian threatened frog species in S Legge, N Robinson, B Scheele, D Lindenmayer, D Southwell & B Wintle (eds) Monitoring threatened species and ecological communities. CSIRO Publishing, Clayton South Victoria. pp 57-68.

Scheele BC, Hunter DA, Banks SC, Pierson JC, Skerratt LF, Webb R, & Driscoll DA (2016). High adult mortality in disease-challenged frog populations increases vulnerability to drought. Journal of Animal Ecology 85, 1453–1460. Scheele BC, Skerratt LF, Hunter DA, Banks SC, Pierson JC, Driscoll DA, Byrne PG, & Berger L (2017). Disease-associated change in an amphibian life-history trait. Oecologia 184, 825– 833.

Skerratt LF, Berger L, Clemann N, Hunter DA, Marantelli G, Newell DA, Philips A, McFadden M, Hines H, Scheele BC, Brannelly LA, Speare R, Versteegen S, Cahsins SD, & West M (2016).

Threatened Species Scientific Committee 21 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Priorities for management of chytridiomycosis in Australia: saving frogs from extinction. Wildlife Research 43, 105-120.

Voyles J, Young S, Berger L, Campbell C, Voyles WF, Dinudom A, Cook D, Webb R, Alford RA, Skerratt LF & Speare R (2009) Pathogenesis of Chytridiomycosis a cause of catastrophic amphibian declines. Science 326(5952), 582–585.

Welsh HHJ & Ollivier LM (1998). Stream amphibians as indicators of ecosystem stress: a case study from California’s redwoods. Ecological Applications 8, 1118-1132.

White AM, Whitford RW & Mahoney MJ (1994). A new species of Litoria (Anura: Hylidae) from eastern Australia. Proceedings of the Linnean Society of New South Wales 114(1), 3-10.

Woinarski JCZ, Legge SM, Woolley LA, Palmer R, Dickman CR, Augusteyn J, Doherty TS, Edwards G, Geyle H, McGregor H, Riley J, Turpin J, Murphy BP (2020). Predation by introduced cats Felis catus on Australian frogs: compilation of species records and estimation of numbers killed. Wildlife Research. Other sources cited in the advice

ALA (Atlas of Living Australia) (2020). Litoria littlejohni. Accessed: 28 February 2020 Available at: https://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:afd.taxon:7ccd824b-542e- 4867-b20f-6c4efaf6288d

CoA (Commonwealth of Australia) (2016). Pathogens and fungi in State of the Environment. Accessed: 12 November 2020 Available at: https://soe.environment.gov.au/theme/land/topic/2016/regional-and-landscape-scale- pressures-invasive-species#figure-lan10occurrences-of-chytrid-fungus-batrachochytrium- dendrobatidis-across-australia-2013--122326

CSIRO and Bureau of Meteorology (2015). Climate Change in Australia Information for Australia’s Natural Resource Management Regions: Technical Report, CSIRO and Bureau of Meteorology, Australia

CSIRO (2007). Climate Change in Australia. Viewed: 26 February 2020 Available at: http://www. climatechangeinaustralia.gov.au/

DELWP (Victorian Department of Environment, Land, Water and Planning) (2020). Victorian Biodiversity Atlas - Litoria littlejohni. Accessed: 24 November 2020 Available at: https://vba.dse.vic.gov.au/vba/index.jsp

DoE (Department of the Environment) (2015). Monitoring and management of subsidence induced by longwall coal mining activity. Accessed: 27 February 2020 Available at:

Threatened Species Scientific Committee 22 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

https://www.environment.gov.au/system/files/resources/8a22c56a-3c83-4812-aa2f- 9d0bc40ac718/files/monitoring-management-subsidence-induced-longwall-coal-mining- activity.pdf

DPIE (NSW Department of Planning, Industry and Environment) (2000). Littlejohn’s tree frog (Litoria littlejohni) – vulnerable species listing. Viewed: 18 February 2020 Available at: https://www.environment.nsw.gov.au/Topics/Animals-and-plants/Threatened- species/NSW-Threatened-Species-Scientific-Committee/Determinations/Final- determinations/2000-2003/Littlejohns-Tree-Frog-Litoria-littlejohni-vulnerable-species- listing

DPIE (NSW Department of Planning, Industry and Environment) (2016). Sydney Basin Bioregion. Viewed: 2 July 2020 Available at https://www.environment.nsw.gov.au/bioregions/SydneyBasinBioregion.htm

DPIE (NSW Department of Planning, Industry and Environment) (2020a). Biodiversity Atlas - Litoria littlejohni. Accessed: 24 November 2020 Available at: https://www.environment.nsw.gov.au/atlaspublicapp/UI_Modules/ATLAS_/AtlasSearch.as px

DPIE (NSW Department of Planning, Industry and Environment) (2020b). Burnt Area Map. Viewed: 03 April 2020 Available: https://www.environment.nsw.gov.au/topics/parks- reserves-and-protected-areas/fire/park-recovery-and-rehabilitation/recovering-from- 2019-20-fires/understanding-the-impact-of-the-2019-20-fires

DSEWPC (Department of Sustainability, Environment, Water, Population and Communities) (2011). Feral Deer. Viewed: 03 March 2020 Available at: https://www.environment.gov.au/system/files/resources/c6679b32-5f03-4839-aa57- 9c5723153b0f/files/fs-feral-deer.pdf

FFM (Forest Fire Management Victoria) (2020). Past bushfires. Viewed: 09 December 2020 Available at: https://www.ffm.vic.gov.au/history-and-incidents/past-bushfires

Hero JM, Gillespie G, Lemckert F, Robertson P & Littlejohn M (2002). Litoria littlejohni Heath Frog, AmphibiaWeb: Information on amphibian biology and conservation. Viewed 20 February 2020 Available at: http://amphibiaweb.org/cgi- bin/amphib_query?query_src=aw_lists_genera_&table=amphib&where- genus=Litoria&where-species=littlejohni

Hunter D (2020). Personal communication by email, 10 August 2020, Senior Threatened Species Officer, NSW Office of Environment and Heritage.

Threatened Species Scientific Committee 23 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

IUCN Standards and Petitions Committee (2019). Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee. Available from http://www.iucnredlist.org/documents/RedListGuidelines.pdf.

Legge S, Woinarski J, Garnett S, Nimmo D, Scheele B, Lintermans M, Mitchell N, Whiterod N and Ferris J (2020). Revised provisional list of animals requiring urgent management intervention. Australian Government Department of Agriculture, Water and the Environment, Canberra. Viewed 25 November 2020 Available at: http://www.environment.gov.au/biodiversity/bushfire-recovery/priority-animals

Mahony M (2020). Personal communication by email, 10 August 2020, Professor, University of Newcastle.

Murray KA, Skerratt L, Marantelli G, Berger L, Hunter D, Mahony M & Hines H (2011). Hygiene protocols for the control of diseases in Australian frogs. Viewed: 18 October 2019 Available at: http://www.environment.gov.au/biodiversity/invasive-species/publications/hygiene- protocols-control-diseases-australian-frogs

OEH (NSW Office of Environment and Heritage) (2017b). Alpine Tree Frog – profile. Viewed: 12 June 2020 Available at: https://www.environment.nsw.gov.au/threatenedSpeciesApp/profile.aspx?id=10494

Scroggie M, Clemann N, & Lumsden L (2011). Survey standards: Large Brown Tree Frog, Litoria littlejohni. The Department of Sustainability and Environment. Viewed: 12 June 2020 Available at: https://www.forestsandreserves.vic.gov.au/__data/assets/pdf_file/0027/29277/2-Large- Brown-Tree-Frog-Survey-Standards-FINALv1.0_2MAY11.pdf

Southwell D (2020). Design considerations for post natural disaster (fire) on-ground assessment of status of species, ecological communities, habitats and threats. Threatened Species Recovery Hub. Viewed: 28 May 2020 Available at: http://www.environment.gov.au/system/files/pages/a8d10ce5-6a49-4fc2-b94d- 575d6d11c547/files/draft-post-fire-rapid-assessment-guide.pdf

Water NSW (2020). Regional Drought Report (June 2020). Viewed: 6 August 2020 Available at: https://www.waternsw.com.au/__data/assets/pdf_file/0019/159400/Regional-Drought- Report-June-2020.pdf

WU (Wildlife Unlimited) (2017). Large Brown Tree Frog – Litoria littlejohni surveys 2017. Unpublished report. Wildlife Unlimited Pty Ltd.

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WU (Wildlife Unlimited) (2020). Summary of key messages from the 2019-2020 landscape scale surveys for Large Brown Tree Frog – Litoria littlejohni. Unpublished report. Wildlife Unlimited Pty Ltd.

Threatened Species Scientific Committee 25 THREATENED SPECIES SCIENTIFIC COMMITTEE

Established under the Environment Protection and Biodiversity Conservation Act 1999 Attachment A: Listing Assessment for Litoria Watsoni Reason for assessment Watson’s Tree Frog is a recently described species. Following genetic analysis, it was revealed that the Littlejohn’s Tree Frog population consists of two highly divergent genetic groups (northern population and southern population), which also show differences in morphology and male advertisement calls (Mahony et al. 2020). Subsequently, the species was split, with the northern population retaining the classification L. littlejohni, while the southern population was named L. watsoni.

Given Littlejohn’s Tree Frog is being assessed for listing as Endangered under the EPBC Act, this assessment follows provision of this new information provided to the Committee to also list Watson’s Tree Frog.

Assessment of eligibility for listing This assessment uses the criteria set out in the EPBC Regulations. The thresholds used correspond with those in the IUCN Red List criteria except where noted in criterion 4, sub- criterion D2. The IUCN criteria are used by Australian jurisdictions to achieve consistent listing assessments through the Common Assessment Method (CAM).

Key assessment parameters Table 3 includes the key assessment parameters used in the assessment of eligibility for listing against the criteria.

Table 2 Key assessment parameters

Metric Estimate used Minimum Maximum Justification in the plausible plausible assessment value value Number of mature No estimate - - There are insufficient data available individuals used to determine the number of mature individuals. However, the population size is thought to be fairly small, with few records from a small number of scattered locations and the species absent from many apparently suitable sites (Lemckert 2010; Gillespie et al. 2016; McCall et al. 2018; ALA 2020; Mahony et al. 2020). Trend contracting The population is suspected to be declining due to ongoing threats (see threats table, above), including the impact from the 2019-20 bushfires and recent severe droughts (2003-09 and 2017-20). Generation time 6 - - The generation length of Watson’s (years) Tree Frog is unknown. However, based on mark-recapture surveys on L. spenceri (Spotted Tree Frog) (conducted by Gillespie 2010, 2011), a similar sized hylid frog from a similar climatic zone, it is estimated to be approximately 6 years.

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Metric Estimate used Minimum Maximum Justification in the plausible plausible assessment value value Extent of 29 062 - - The extent of occurrence (EOO) has occurrence (km2) been calculated using records from the past 20 years (2000-20). Despite limited targeted surveys for the species, genetic analysis by Mahony et al. (2020) provides a good understanding of the extent of the distribution range. Trend contracting Throughout the distribution, the Watson’s Tree Frog population is suspected to be declining (Gillespie et al. 2016; McCall et al. 2018; Mahony et al. 2020). Bd is implicated in a suspected population decline, beginning in the 1990s (Mahony et al. 2020), and more recent declines are suspected following severe droughts (2003-09 and 2017-20) and the 2019-20 bushfires. Area of <500 224 332 The minimum plausible value has Occupancy (km2) been calculated using records from the past 20 years (2000-20). Due to the limited number of targeted surveys conducted (Gillespie et al. 2016; Mahony et al. 2020), this may not capture the full extent of the occupied sites. The maximum plausible value uses records from the past 40 years (1980-2020), before the Bd-associated decline in the 1990s. However, only some of this habitat may now be occupied.

Given the minimum and maximum figures are close together, the limits of the distribution are well defined (post taxonomic revision) (Mahony et al. 2020), and the likely ongoing population reduction from Bd, recent drought, and the 2019-20 bushfires, it is assessed that the AOO is under 500 km2, which meets the threshold for Endangered listing under Criterion 2 (see below). Trend contracting See section on EOO, above.

Number of There are insufficient data available subpopulations to determine the number of subpopulations.

Threatened Species Scientific Committee 27 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Metric Estimate used Minimum Maximum Justification in the plausible plausible assessment value value Trend contracting See section on EOO, above. Basis of Insufficient data assessment of subpopulation number

No. locations 3 3 5 Watson’s Tree Frog is known to occur in three locations. These are: the south-eastern margin of the Sydney Basin Bioregion, the NSW south-coast (south of Nowra) to the latitude of the Australian Capital Territory, and the border region of south-east NSW and East Gippsland, Victoria (see Map 1). However, it is possible that other locations are present in between. The EOO is relatively large in comparison to the AOO (Mahony et al. 2020) and contains large areas of seemingly suitable habitat that is not subject to regular targeted surveying (Gillespie et al. 2016). This gives a range of 3–5 plausible locations. This meets the sub-criterion threshold for Endangered listing under Criterion 2 (see below). Trend Contracting The species has been infrequently recorded on the NSW south-coast, and surveys in the southern part of the distribution range indicate that the population has declined (Gillespie 2016; McCall et al. 2018; ALA 2020; DELWP 2020; DPIE 2020a).

Threatened Species Scientific Committee 28 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Metric Estimate used Minimum Maximum Justification in the plausible plausible assessment value value Basis of A location is defined by the IUCN Standards and Petitions Committee (2019) as a assessment of “geographically or ecologically distinct area in which a single threatening event can rapidly location number affect [in one generation or 3 years] all individuals of the taxon present [to the point that the population cannot recover in that location]”. Under this definition, the proximity of sites is an important consideration. Sites that are close to each other experience more similar (more correlated) conditions over time than sites that are far away from each other. This is demonstrated by the patchy nature of bushfires across the landscape and the varying Bd-induced mortality rate along altitudinal gradients for many frog species. However, the extent and severity of the 2019-20 bushfires has recalibrated the size of an area that can potentially be considered one location, particularly for species that face a greater direct mortality threat from fire and smoke (cannot flee or take refuge) and are vulnerable in the post-fire landscape, having late-successional forest habitat requirements (breeding, shelter, and foraging), such as Watson’s Tree Frog. Analysis of the impact of the 2019-20 bushfires by a team from the National Environmental Science Program (NESP) Threatened Species Recovery Hub shows that 85 % of the range of Watson’s Tree Frog was burnt, and nearly half was covered by a high to very high severity fire (44 %). Through an expert elicitation process, it is estimated that one year after the fires, the species has experienced an overall decline from pre-fire levels of 41 % and that the population loss could be as large as 62 % (bound of 80 % confidence limits).

Despite these estimated declines, the potential impact from any threat, including bushfires, is tempered by the relatively large dispersal of the Watson’s Tree Frog population across the landscape, with AOO found in patches that are geographically separated from each other by wide expanses of either unoccupied or unsuitable habitat. Therefore, the entire population is unlikely to be impacted by the same threat, at the same level of severity, at the same time, such that it would decline to a level that recovery is unlikely.

Subsequently, the number of locations is assessed to be 3, in line with the roughly grouped areas (detailed above) where records of Watson’s Tree Frog sites are found to be relatively contiguous, are of a size that could realistically be entirely burnt by high severity fire, and have little chance of recolonisation given their isolation from each other. Fragmentation Watson’s Tree Frog has a patchy but widespread distribution (Lemckert 2010; Gillespie et al. 2016; Mahony et al. 2020), being only been recorded at low numbers at known sites (Lemckert 2004 cited in Daly & Craven 2007; DEWHA 2008; DELWP 2020; DPIE 2020a). However, given the lack of long-term monitoring at many sites across the distribution, it is unclear how vulnerable individual subpopulations are to extirpation. In particular, whether the population is severely fragmented, requiring 50% of the AOO to be in patches that are too small to support a viable population (IUCN Standards and Petitions Committee 2019). Fluctuations Not known to be subject to extreme fluctuations in EOO, AOO, number of subpopulations, locations or mature individuals. No parameter has been shown to have changed by an order of magnitude by the 2019/20 bushfire.

Threatened Species Scientific Committee 29 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Criterion 1 Population size reduction

Reduction in total numbers (measured over the longer of 10 years or 3 generations) based on any of A1 to A4

– Critically Endangered Endangered Vulnerable Very severe reduction Severe reduction Substantial reduction

A1

A2, A3, A4 ≥ 90% ≥ 70% ≥ 50%

A1 Population reduction observed, estimated,≥ 80% inferred or suspected in ≥the 50% (a) direct≥ 30% observation [except past and the causes of the reduction are clearly reversible AND A3] understood AND ceased. (b) an index of abundance appropriate to the taxon A2 Population reduction observed, estimated, inferred or suspected in the (c) a decline in area of past where the causes of the reduction may not have ceased OR may not occupancy, extent of be understood OR may not be reversible. occurrence and/or quality of habitat A3 Population reduction, projected or suspected to be met in the future (up Based on (d) actual or potential levels of any of the to a maximum of 100 years) [(a) cannot be used for A3] exploitation following (e) the effects of introduced A4 An observed, estimated, inferred, projected or suspected population taxa, hybridization, reduction where the time period must include both the past and the pathogens, pollutants, future (up to a max. of 100 years in future), and where the causes of competitors or parasites reduction may not have ceased OR may not be understood OR may not be reversible.

Criterion 1 evidence Eligible under Criterion 1 A4ce for listing as Endangered

The generation length of Watson’s Tree Frog is unknown. However, based on the population demographics of the Spotted Tree Frog (a similar sized hylid frog in a similar climatic zone) it is estimated to be approximately six years (see Table 3). This gives a timeframe of 18 years for this criterion, but this should be adjusted as species-specific ecological knowledge improves.

A population decline of Littlejohn’s Tree Frog and (by extension) Watson’s Tree Frog is suspected to have occurred, beginning in the 1990s (Gillespie & Hines 1999; Gillespie et al. 2018; Mahony et al. 2020). Monitoring at a small number of sites indicating that this decline may have occurred across a significant portion of the distribution range (Gillespie et al. 2018), with both species now reliably found at only a few isolated sites, and mostly in low abundance. Extensive surveys (carried out during 2017) of 700 potential breeding sites across the distribution range found these species at only 27 sites (McCall et al. 2018). In NSW, Watson’s Tree Frog has infrequently been recorded south of Nowra (ALA 2020; DPIE 2020a), and in Victoria, surveys (2009-19) have failed to detect Watson’s Tree Frog at most historical sites (finding it at 31 sites) (Gillespie et al. 2016; WU 2017, 2020; DELWP 2020).

This suspected decline began outside of the three generation timeframe for evaluating a change in population size. However, the fragmented and sparse nature of the population, in combination with the species low dispersal ability and associated poor recolonisation potential (DPIE 2000), reduces the likelihood of subpopulation recovery from stochastic events and lowers the species

Threatened Species Scientific Committee 30 Litoria watsoni (Watson’s Tree Frog) Conservation Advice resilience to threatening processes, including habitat disturbance and loss, climate change (increased frequency and severity of drought and bushfires), and disease (Bd).

Watson’s Tree Frog is a forest dependent species. Therefore, it is likely that disturbance to forest habitat, including clear-felling and conversion to softwood plantations, has an adverse effect on the population (Gardner et al. 2007; Gillespie et al. 2016). Most of the known distribution range is outside of reserves (National Parks and Wildlife Service estate) and subject to disturbance from primary industries (Hunter et al. 2018; Mahony et al. 2020). In particular, much of the known habitat in Victoria has been logged (Gillespie et al. 2016).

Adding to a loss of forest habitat, the availability of breeding sites, particularly ephemeral ponds, is likely to have been reduced following recent extreme drought events. Both the Millennium drought (2003-09) and the most recent drought (2017-20), which was the worst on record in many regions across NSW (Water NSW 2020), are likely to have reduced Watson’s Tree Frog recruitment over the last three generations. A reduction in the number of suitable breeding sites was likely compounded by a reduced level of breeding activity, with male calling closely associated with heavy rainfall (White et al. 1994; Lemckert 2010; OEH 2017a). Targeted surveys in Victoria in 2017 and 2019-20 revealed a reduction in frogs detected over the course of the most recent drought. In 2017, Watson’s Tree Frog was detected at 3.2 percent of surveyed sites (21 of 660 sites), when surveys were repeated two years into the drought (at the same sites where water was still present and additional sites identified as potential habitat), frogs were recorded at less than half of the previous sites, at only 1.4 percent of sites (nine of 658 sites) (WU 2017, 2019).

Compounding population declines from the recent drought, the Watson’s Tree Frog population is likely greatly reduced following the 2019-20 bushfires that burnt across southern and eastern Australia. The fires may have accelerated any population decline, through direct mortality, and the unfavourable post-fire conditions (loss of shelter, increased susceptibility to predators, and loss of prey), as well as a reduction in future recruitment (egg and tadpole death and breeding site degradation). An analysis by a team from the NESP Threatened Species Recovery Hub shows that a large proportion of the range of Watson’s Tree Frog was affected by these fires: 44 percent was burnt in high to very high severity fire, and a further 41 percent was burnt in low to moderate severity fire. A structured expert elicitation process was used to estimate the proportional population change for this species from pre-fire levels to immediately after the fire and then out to three generations after the fire, when exposed to fires of varying severity. These results, combined with the spatial analyses of fire overlap, suggest that one year after the fire, the species has experienced an overall decline of 41 percent from pre-fire levels, but that the decline could be as large as 62 percent (bound of 80 percent confidence limits). After three generations, the estimate for the overall population decline relative to the pre-fire population is predicted to be 43 percent, but potentially as much as 67 percent (bound of 80 percent confidence limit). For comparison, experts also estimated the population change over time in the absence of fire; by three generations, the overall population of Watson’s Tree Frogs after the fire was estimated to be 26 percent lower than it would have been had the 2019-20 fire not occurred.

Despite the uncertainty over the extent of the impact of the bushfires, a precautionary approach on the severity of the population reduction as a result of the recent droughts and bushfires has been taken. The population was already diminished and fragmented, likely through disease (Bd)

Threatened Species Scientific Committee 31 Litoria watsoni (Watson’s Tree Frog) Conservation Advice and habitat disturbance, and vulnerable to stochastic events. Therefore, the frequency, severity, and extent of recent droughts and bushfires is expected to have severely reduced the population. Subsequently, a reduction of greater than 50 percent is suspected, with the impact from the fires to continue to have a detrimental impact for future generations. This meets the Endangered threshold under subcriterion A4(c).

Although not confirmed, it is highly likely that Watson’s Tree Frog has been exposed to Bd (Gillespie et al. 2016) and the suspected declines in population during the 1990s has been broadly linked with its emergence (Gillespie et al. 2016; Gillespie et al. 2018; Mahony 2020). The impact of Bd on Watson’s Tree Frog has not been assessed, but given the persistence of the disease in eastern Australia (Voyles et al. 2009; Newell et al. 2013), and that frog populations have been reinfected even after multiple exposures (Cashins et al. 2013; Berger et al. 2016), Bd is viewed as an ongoing potential threat to Watson’s Tree Frog recovery, thereby meeting subcriterion (e).

The data presented above appear to demonstrate that the species is eligible for listing as Endangered (A4(c)(e)) under this criterion. However, the purpose of this consultation document 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 2 Geographic distribution as indicators for either extent of occurrence AND/OR area of occupancy

– Critically Endangered Vulnerable Endangered Restricted Limited Very restricted

B1. Extent of occurrence (EOO) < 100 km2 < 5,000 km2 < 20,000 km2

B2. Area of occupancy (AOO) < 10 km2 < 500 km2 < 2,000 km2

AND at least 2 of the following 3 conditions:

(a) Severely fragmented OR Number = 1 ≤ 5 ≤ 10 of locations

(b) Continuing decline observed, estimated, inferred or projected in any of: (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: (i) extent of occurrence; (ii) area of occupancy; (iii) number of locations or subpopulations; (iv) number of mature individuals

Criterion 2 evidence Eligible under Criterion 2 B2ab(i,ii,iii,iv,v) for listing as Endangered.

The area of occupancy (AOO) for Watson’s Tree Frog has been calculated as a range between 224 km2 and 332 km2 and the extent of occurrence (EOO) calculated at 29 062 km2 (see Table 3, above). The minimum plausible AOO value and the EOO value were calculated using the

Threatened Species Scientific Committee 32 Litoria watsoni (Watson’s Tree Frog) Conservation Advice methods outlined in the IUCN guidelines using record data over a 20-year period (2000–20) obtained from state governments, museums, and CSIRO. The maximum plausible AOO value was calculated using all distribution records from the last 40 years (1980–2020).

The minimum plausible AOO value is calculated over a relatively short period to reflect suspected recent declines in the population. However, as long-term monitoring for Watson’s Tree Frog is limited, with portions of the distribution range having not been surveyed for the species (Gillespie et al. 2016, 2018; Mahony et al. 2020), additional subpopulations may be present. Subsequently this value may under-estimate the number of occupied sites. The maximum plausible AOO value is calculated over a longer timeframe to allows additional point records to be included, particularly records from before the Bd-implicated decline in the 1990s. However, recent surveys (Gillespie et al. 2016; WU 2017, 2020; McCall et al. 2018; Moses & Mahony unpublished data cited in Mahony et al. 2020; DELWP 2020) indicate that the species has declined, with many historical sites no longer occupied. Subsequently, this value may over-estimate the number of occupied sites.

Given the minimum and maximum AOO values are close together, and both meet the threshold for listing as Endangered, and that catastrophic events have occurred across the distribution range over the last 40 years (Bd, drought, and bushfires), the AOO is considered to be under 500km2. Therefore, the AOO meets the threshold for listing as Endangered under subcriterion B2.

The number of locations identified is three, meeting the threshold for listing as Endangered under subcriterion (a) (see Table 3). The three locations are:

1. the northern reach of the distribution range, constituting the south-eastern margin of the Sydney Basin Bioregion; 2. the NSW south-coast (south of Nowra) to the latitude of the ACT; 3. the southern reach of the distribution range, including sites in far south-east NSW and across the border into East Gippsland, Victoria.

Given the extent of the 2019-20 bushfires, which are believed to have overlapped with 85 percent of the Watson’s Tree Frog distribution, with 44 percent covered by a high to very high severity fire (see Criterion 1), these locations could individually be rapidly affected by a single bushfire event. In addition, all three locations are restricted, with the species only being consistently found on the Woronora Plateau on the south-eastern margin of the Sydney Basin Bioregion (Mahony et al. 2020). The species has infrequently been recorded on the NSW south-coast south (ALA 2020; DPIE 2020a) and in Victoria, records have been restricted to East Gippsland since rediscovery (Gillespie et. al. 2016; WU 2017, 2020; DELWP 2020). The small, localised nature of some sites at these locations increases the species vulnerability to bushfire, as areas of high intensity burn could affect a larger proportion of the population than if the population was more widely distributed.

A continuing decline in EOO, AOO, extent and/or quality of habitat (and therefore number of locations or subpopulations), and number of mature individuals may be inferred based on the

Threatened Species Scientific Committee 33 Litoria watsoni (Watson’s Tree Frog) Conservation Advice ongoing threats to Watson’s Tree Frog, in particular habitat loss, climate change, and disease (Bd) (see Criterion 1), thereby meeting subcriterion (b)(i,ii,iii,iv,v).

The data presented above appear to demonstrate that the species is eligible for listing as Endangered (B2(a)(b)(i,ii,iii,iv,v)) under this criterion. However, the purpose of this consultation document is to elicit additional information to better understand the species’ status. This conclusion should therefore be considered tentative at this stage, as it may be changed as a result of responses to this consultation process.

Criterion 3 Population size and decline

– Critically Endangered Vulnerable Endangered Low Limited Very low

Estimated number of mature individuals < 250 < 2,500 < 10,000

AND either (C1) or (C2) is true

C1. An observed, estimated or projected Very high rate High rate Substantial rate continuing decline of at least (up to a 25% in 3 years or 1 20% in 5 years or 2 10% in 10 years or max. of 100 years in future) generation generation 3 generations (whichever is (whichever is (whichever is longer) longer) longer)

C2. An observed, estimated, projected or inferred continuing decline AND its geographic distribution is precarious for its survival based on at least 1 of the following 3 conditions:

(i) Number of mature individuals in each subpopulation ≤ 50 ≤ 250 ≤ 1,000 (a) (ii) % of mature individuals in one 90 – 100% 95 – 100% 100% subpopulation =

(b) Extreme fluctuations in the number of mature individuals

Criterion 3 evidence Insufficient data to determine eligibility

There is no estimate for the number of adult Watson’s Tree Frogs (Gillespie et al. 2016, 2018). No specific ecological studies have been undertaken, and available data indicate only where and when the species was previously found, rather than providing an accurate picture of the distribution (DEPI 2014; Gillespie et al. 2016). Nevertheless, the population size is thought to be small. Despite its relatively large geographical range, there are very few records of Watson’s Tree Frog (ALA 2020; DELWP 2020; DPIE 2020a; Mahony et al. 2020). The number of sites where this species has been recorded is low (Gillespie 2016; WU 2017, 2020; McCall et al. 2018; Mahony et al. 2020), with most sightings no more than four frogs at any site (Lemckert 2004 cited in Daly & Craven 2007; DEWHA 2008; WU 2017, 2020; ALA 2020).

Threatened Species Scientific Committee 34 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

The data presented suggest that there are insufficient data to demonstrate if the species is eligible for listing under this criterion. However, the purpose of this conservation 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 4 Number of mature individuals

– Critically Endangered Endangered Vulnerable Extremely low Very Low Low

D. Number of mature individuals < 50 < 250 < 1,000

D2.1 Only applies to the Vulnerable category D2. Typically: area of Restricted area of occupancy or number occupancy < 20 km2 or - - of locations with a plausible future threat number of locations that could drive the species to critically 5 endangered or Extinct in a very short time ≤

1 The IUCN Red List Criterion D allows for species to be listed as Vulnerable under Criterion D2. The corresponding Criterion 4 in the EPBC Regulations does not currently include the provision for listing a species under D2. As such, a species cannot currently be listed under the EPBC Act under Criterion D2 only. However, assessments may include information relevant to D2. This information will not be considered by the Committee in making its recommendation of the species’ eligibility for listing under the EPBC Act, but may assist other jurisdictions to adopt the assessment outcome under the common assessment method.

Criterion 4 evidence Insufficient data to determine eligibility

There is no estimate for the number of adult Watson’s Tree Frogs (see Criterion 3).

The data presented suggest there are insufficient data to demonstrate if the species is eligible for listing under this criterion. However, the purpose of this conservation 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.

In addition, although the number of locations is less than five (see Criterion 2), there are insufficient data to demonstrate if the species is eligible for listing under subcriterion D2. Population demographics are poorly understood and how the species has been impacted and responds to significant threats (Bd and bushfires) has not been ascertained. Therefore, it is uncertain whether a plausible future threat could drive the species towards extinction in a very short time (within two generations).

Threatened Species Scientific Committee 35 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

Criterion 5 Quantitative analysis

– Critically Endangered Vulnerable Endangered Near future Medium-term future Immediate future

Indicating the probability of generations, 5 generations,

extinction in the wild to be: whichever≥ 50% in 10 is years longer or 3 whichever≥ 20% in 20 is years longer or (100 years max.) (100 years max.) ≥ 10% in 100 years

Criterion 5 evidence Insufficient data to determine eligibility

Population viability analysis has not been undertaken. Therefore, there is insufficient information to determine the eligibility of the species for listing in any category under this criterion. However, the purpose of this conservation advice is to elicit additional information to better understand the species’ status. This conclusion should therefore be considered tentative at this stage, as it may be changed as a result of responses to this consultation process.

Adequacy of survey The survey effort has been considered adequate and there is sufficient scientific evidence to support the assessment.

Listing and Recovery Plan Recommendations No recovery plan is in place for Watson’s Tree Frog.

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

Threatened Species Scientific Committee 36 Litoria watsoni (Watson’s Tree Frog) Conservation Advice

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This publication is available at the SPRAT profile for Litoria watsoni (Watson’s Tree Frog). Department of Agriculture, Water and the Environment GPO Box 858, Canberra ACT 2601 Telephone 1800 900 090 Web awe.gov.au

The Australian Government acting through the Department of Agriculture, Water and the Environment has exercised due care and skill in preparing and compiling the information and data in this publication. Notwithstanding, the Department of Agriculture, Water and the Environment, its employees and advisers disclaim all liability, including liability for negligence and for any loss, damage, injury, expense or cost incurred by any person as a result of accessing, using or relying on any of the information or data in this publication to the maximum extent permitted by law. Version history table Document type Title Date [dd mm yyyy] – – –

Threatened Species Scientific Committee 37