Manning River Helmeted Turtle

2019 Autumn Survey Report

Ecology I Environment I Heritage

Citation: Redleaf Environmental (2019) Helmeted Turtle 2019 Autumn Survey Report. Prepared for the NSW Office of Environment and Heritage.

Contact Details Dr Darren Fielder B.App.Sci, PhD M 0407 234 986 F 07 4659 5839 E [email protected]

Mrs Sarah Grady M 0417 602 693 F 07 4659 5839 E [email protected]

A PO Box 3564 Toowoomba 4350

Cover Photo: Rowleys River, Strike-A-Light Station. Darren Fielder Redleaf Environmental

© Red Leaf Projects Pty Ltd trading as Redleaf Environmental Apart from fair dealing for the purposes of private study, research, criticism, or review as permitted under the Copyright Act, no part of this report, its attachments or appendices may be reproduced by any process without the written consent of Redleaf Environmental. All enquiries should be directed to Redleaf Environmental. A person using Redleaf Environmental documents or data accepts the risk of: a) Using the documents or data in electronic form without requesting and checking them for accuracy against the original hard copy version. b) Using the documents or data for any purpose not agreed to in writing by Redleaf Environmental.

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DOCUMENT CONTROL

Report title Manning River Helmeted Turtle 2019 Autumn Survey Report Document ID Project Number OEH19001 File Path NSW Office of Environment Client Client Contact Andrew Steed and Heritage Prepared Rev Date Revision Details/Status Verifier Approver by 1 26/04/2019 Draft report issued to OEH DF SG DF 2 3 Current Revision Final Report

Approval

Signature Signature

Name Dr Darren Fielder Name Mrs Sarah Grady Senior Environmental Title Principal Scientist Title Scientist

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Contents Contents iv 1 Introduction 1 1.1 Background 1 1.2 Project objectives 2 2 Methods 5 3 Field assessment 6 3.1 Survey limitations 6 3.2 Snorkel surveys 6 3.3 Landholder Consent 8 4 Results 9 4.1 Overall results for 2018-2019 9 4.2 Catch per unit effort 10 4.3 Manning River Helmeted Turtle 10 5 Discussion 12 5.1 Turtle reproduction and population demographics 12 5.1.1 Recruitment 12 5.1.2 Sex ratios 12 5.1.3 Mating behaviour 12 5.2 Threatening processes 12 5.2.1 Nest predation 12 5.2.2 Eye cataracts 13 5.2.3 Habitat modification 13 5.2.4 Competition and hybridisation with Emydura macquarii 14 6 Conservation considerations 15 6.1 Future management actions 15 7 References 16 Appendix A – Site photos 18 Incidental records and photos 23

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1 Introduction 1.1 Background Redleaf Environmental was engaged by the NSW Office of Environment and Heritage to conduct a second season of surveys during March-April 2019 for the endangered Manning River Helmeted Turtle Myuchelys purvisi across sites in the Manning River Catchment (Table 1 and Figure 1). The first survey in April 2018 is reported separately (Redleaf Environmental 2018). However, both datasets are included here to provide a clearer understanding of the findings from across two seasons of data collection.

Adult female, Cooplacurripa River Immature turtle, Rowleys River

Table 1 Site location details Site Year Location River Latitude Longitude 1 2018 Rocks Crossing TSR Nowendoc - 31.7612581 152.0746012 2 2018 Dalrae Station, 5077 Nowendoc Road, Upper Nowendoc - Nowendoc 31.6964033 151.9630584 3 2018 Cooplacurripa Station Lower TSR Cooplacurripa - 31.6228902 151.9468186 4 2018 Mummel River Yard Creek Crown Land Mummel - 31.5177815 151.9188222 5 2018 Rowleys River, 4802 Cells Road, Cells River Rowleys - 31.6495959 152.0605029 6 2018 Cooplacurripa Station, Nowendoc Road Upper Cooplacurripa - TSR 31.6043379 151.8929738 7a 2018 Dalrae Station, 5077 Nowendoc Road, Lower Nowendoc Nowendoc -31.699116 151.9895817 8 2018 Obergs Trail Barakee National Park Nowendoc - 31.6631927 151.8923409 9 2018 Nowendoc TSR North, Nowendoc Township Nowendoc - 31.5092892 151.7046865 10 2018 Carabeen Creek Management Trail, Mummel Mummel - Gulf National Park 31.4274119 151.876412

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Site Year Location River Latitude Longitude 11 2019 Top Station 12 km east of Nowendoc Cooplacurripa -31.494886 151.811267 12 2019 Cooplacurripa Station on Mummel Mummel -31.533029 151.924824 13 2019 Cooplacurripa Station on Mummel Mummel -31.532394 151.924375 14 2019 Cooplacurripa Station on Mummel Mummel -31.530164 151.922087 15 2019 Cooplacurripa Station on Mummel Mummel -31.538683 151.930723 16 2019 Cooplacurripa Station, 1.7 km SW of the Cooplacurripa -31.620943 151.910175 homestead 17 2019 Cooplacurripa Station, 1.7 km SW of the Cooplacurripa -31.623829 151.910843 homestead 18 2019 Cooplacurripa Station, 1.7 km SW of the Cooplacurripa -31.616711 151.916009 homestead 19 2019 Strike A Light Station, at the pump hole Rowleys -31.591396 152.047116 20 2019 Strike A Light Station, downstream from the Rowleys -31.596236 152.050387 pump hole 21 2019 Strike A Light Station, downstream from the Rowleys -31.598184 152.050607 pump hole 22 2019 Terranbella Station, at the homestead Rowleys -31.553014 152.065233 23 2019 Strike A Light Station, at the norther property Rowleys -31.577712 152.053312 boundary. 24 2019 Les McKensie, big waterhole Bobin Creek -31.672922 152.262506 25 2019 Les McKensie, campground Bobin Creek -31.676915 152.262489 26 2019 Les McKensie, downstream Bobin Creek -31.679686 152.264692 27 2019 Les McKensie, upstream waterhole Bobin Creek -31.674775 152.248673 28 2019 Dingo Bend -31.737224 152.300521 29 2019 Peter Fotheringham Station Mummel -31.566489 151.951919 30 2019 Terranbella Station, 1 km upstream from Rowleys -31.542625 152.064824 homestead

1.2 Project objectives The aim of this project is to assist the recovery of the Manning River Helmeted Turtle (Myuchelys purvisi), a species endemic to the Manning River system and listed as endangered under the NSW Biodiversity Conservation Act, 2016. It has been assigned to the Data-deficient stream of the Saving our Species program that is administered by the NSW Office of Environment and Heritage. The specific aims are: • Build a better understanding of the distribution of Myuchelys purvisi in the Manning valley • Build a better understanding of the distribution of Emydura macquarii in the Manning valley • Understand the extent, prevalence and severity of threat to Myuchelys purvisi • Provide the basis for the development of site-based management activities • Contribution to movement of this species from the data-deficient management stream. These objectives form part of a larger program to manage Myuchelys purvisi. Data collected as part of this scope will be used to inform a change in management streams and subsequent management and a monitoring actions.

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To help achieve these aims, the project aimed to undertake trapping and hand capture of M. purvisi at numerous locations to determine the extent of its distribution, its population demographics and health and the threats to the species, in particular, the distribution and abundance of, and possible hybridisation with, the Macquarie turtle, Emydura macquarii, which is believed to have been introduced to the Manning River system. The results of these surveys will help to identify specific locations where targeted programs will be implemented to further assist the recovery of the M. purvisi. The surveys will provide the basis of an ongoing monitoring program where capture effort at selected locations will be replicated in subsequent years. The number of populations and population sizes are unknown. Available records, potential habitat and topography suggest that there are populations in at least five of the seven sub-catchments of the Manning River, however there has been a lack of targeted surveys in the more remote and inaccessible upper catchments so the habitat value of upper catchment areas is unknown as is the presence of this species in conservation reserves. Recently the abundance of M. purvisi appears to have declined dramatically (J. Cann pers. comm. April 2016). The total population size of M. purvisi is inferred to be moderately low. Terrestrial movements between river systems are unlikely. Thus, the distribution of M. purvisi is inferred to be severely fragmented (NSW Scientific Committee 2017). Myuchelys purvisi faces multiple threats including predation, illegal collecting, habitat degradation and, potentially, disease as well as competition and hybridisation with E. macquarii. Short-necked turtles are thought to be particularly vulnerable to fox predation because they are unable to fully retract their limbs and head (Spencer and Thompson 2005). Nest predation rates for M. purvisi are unknown. Recent detection of the nests of Bell’s Turtle (M. bellii) found a predation rate of nearly 90%, with 6 female turtles found preyed on near the entrance to a fox den (M. Dillon, Local Land Services, pers. comm. December 2017).

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Figure 1: Location map of the Manning River Turtle survey sites.

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2 Methods The surveys were conducted under approved scientific and ethics approvals: • Fisheries Permit: P18/0011-1.0 (Fisheries Management Act 1994) • Scientific Licence: SL102062 (Biodiversity Conservation Act 2016) • Ethics approval: 180313/02 through OEH Animal Ethics Committee (2019) Redleaf’s ecologists used a combination of trapping and snorkelling across 20 locations in 2019 and 10 locations from 2018. The techniques used at each site were dependent upon the clarity of the water, suitability for fyke nets and accessibility to the aquatic environment. In some locations where water clarity was good, both trapping and snorkelling were undertaken to provide information on the detectability of M. purvisi. Surveys and handling of turtles included: • net trapping using cathedral nets and fyke nets; • capture of animals by snorkelling; • holding of animals after removal from the water for no more than 6 hours in nally bins, out of the sun. Turtles will be covered with rubber mats and lids placed on bins to calm turtles and limit movement; • measuring of animals (straight carapace (shell) and plastron (front of shell on “chest”) lengths with callipers); • weighing on electronic scales; • abdominal palpation of females for eggs; • marking of animals with notching or drilling of scutes less than 5mm in depth or diameter (max 3 scutes); and • release of animals at the pool of capture Surveys were conducted in accordance with DPI Procedure – Effective decontamination of equipment used in association with a suspected pathogen impacting Myuchelys georgesi V3, 24/3/15.

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3 Field assessment The sites were assessed by Redleaf ecologist Darren Fielder and Shannon Michael during the 24th March to 3rd April 2019. 3.1 Survey limitations Ecological surveys have inherent biases because of the cryptic nature of some species, search effort, time- of-year (reduced turtle activity during cooler months of the year) and the climatic conditions under which the surveys were conducted. The results of this turtle survey should not be regarded as conclusive evidence that M. purvisi do not occur within the study sites. In stating these limitations, the efficacy of the turtle survey carried out at is highly effective. Consequently, the data and recommendations made here provide a reliable and true representation of the values of the site. 3.2 Snorkel surveys Snorkelling was undertaken where water clarity allowed. Not all sites during the survey were able to be snorkelled due to elevated turbidity from recent rainfall in the upper catchments with small turbid laden flows moving through the system. The following table provides a record of extent where snorkelling was completed.

River Reach Snorkel survey area Mummel River, Cooplacurripa Station, survey effort 2,000 m. Water clarity was good with some minor turbidity from recent rainfall further upstream. There were several deeper sections to 2-3 m.

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River Reach Snorkel survey area Cooplacurripa River, Cooplacurripa Station, survey effort 1,950 m. Heavily impacted river reach from unfettered stock access. Long, wide and shallow stretches with extensive algal and macrophyte growth present choking the waterway. Several deeper sections with clear water. Water clarity was good.

Rowleys River at Strike- A-Light Station, survey effort 3,572 m reach. Excellent water clarity. Very large waterholes to >6 m depth present. However, most deeper waterholes to 3.5 m. Shaded stream from adjacent riparian vegetation.

Rowleys River, Terranbanella Station, survey effort 1,712 m reach. Large waterholes to 3.5 m. Water clarity was excellent. Some wide, shallow reaches present also.

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River Reach Snorkel survey area Bobin Creek, survey effort 5,580 m reach. Small stream, near 100% shaded by rainforest riparian vegetation. There were three large pools to 3 m depth. They were isolated from each other by most of the stream being 0.2 – 0.4 m depth. Water clarity was excellent. Very cold water estimated at 15 degrees.

Dingo Creek, survey effort 1,076 m reach. Water clarity was limited because of elevated turbidity. The water temperature was cold (estimated ~15 degrees). Very shallow stream (0.4 m) with a few deeper areas to 1.5 m.

3.3 Landholder consent Landholder consent and land access was arranged by the NSW Office of Environment and Heritage.

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4 Results 4.1 Overall results for 2018-2019 The 10 sites (2018) and 20 sites (2019) were surveyed with the capture effort and results presented in Table 2. The survey resulted in the capture of 61 M. purvisi, 48 C. longicollis and one E. macquarii turtle. In addition, there was a good abundance of eels (A. reinhardtii) at all locations. Table 2 Survey effort and capture results including incidental recordings (2018-19)

Site Year Survey Effort Turtles Incidental Records

tii tii

(hrs)

anatinus

purvisi

Trap (hrs) Fyke(hrs) Snorkel M. longicollisC. E. macquarii Anguilla reinhard Ornithorhync hus Tandanus tandanus Euastacussp. 1 2018 120 1 3 2 2018 100 12.5 1 1 3 1 3 2018 144 18 2 1 11 7 1 11 4 2018 128 2.5 11 3 2 1 5 2018 112 24 2 4 1 4 1 6 2018 152 19 1 2 9 4 1 2 7a 2018 128 1 1 1 3 8 2018 116 14.5 1 1 3 9 2018 120 1 1 10 2018 * 2 1 2 11 2019 108.5 17 1 1 12 2019 104 15 1 13 2019 1.5 1 1 14 2019 1.5 1 1 15 2019 4 2 2 1 16 2019 120 17 1 4 17 2019 3 5 10 1 18 2019 4 1 1 19 2019 56 48 2 1 20 2019 2 1 1 21 2019 2 2 5 1 22 2019 2 4 1 1 23 2019 4 16 1 24 2019 5 1 1 1 25 2019 52 1 1 1 26 2019 2 1 27 2019 4 1 1 28 2019 4 1 29 2019 104 3 1 3 2 5 30 2019 4 1 1 1 Totals 1612 237 58 61 48 1 53 8 18 5 * Note: trapping was not possible due to depth of waterholes and rugged terrain preventing carrying traps into more suitable waterholes downstream.

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4.2 Catch per unit effort The survey captured M. purvisi at 21 of the 30 sites (Figure 2) and was most abundant in the Mummel River (Site 4; n = 19) and Rowleys River (Site 23; n = 28). The most common method of capture of all turtles was from snorkelling (only 10 M. purvisi were captured using traps or fykes) (Table 3). Snorkelling yielded the most turtles per hour effort (1.41) with fyke (0.029) and cathedral traps (0.012) yielding few turtles in comparison. Table 3 Survey effort and capture results including incidental recordings Method M. purvisi C. longicollis E. macquarii Effort (hours) Total Capture rates Trapping 7 12 1 1612 20 0.012 Fyke 3 4 237 7 0.029 Snorkelling 51 31 58 82 1.41 Hand capture 1 1 Total 61 48 1 110

Table 4 Capture results by tributary Tributary M. purvisi C. longicollis E. macquarii

Bobin Creek 2

Dingo Creek

Cooplacurripa River 10 35

Mummel River 19 4 2 1 1

Rowleys River 28 8 Total 61 48 1

4.3 Manning River Helmeted Turtle The survey captured turtles across most size classes. There were six (6) immature females, two (2) immature males and 10 unsexed immature turtles caught. There were 28 adult females and 15 adult males captured (Figures 2 and 3). The largest female was 22.47 cm straight carapace length (CL) with a mass of 1,554 g. The largest male caught was CL 17.18 cm with a mass of 616 g. The smallest immature turtle caught was CL 8.07 cm and a mass of just 71 g.

Species Mature Mature Immature Immature Unsexed % Immature F/M ratio Female Male Female Male M. purvisi 28 15 6 2 10 29.5% 2:1

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Manning River Helmeted Turtle Autumn Surveys 2018-2019 8

7

6 Immature 5 turtles

4

3 Tail Tail Length(cm)

2

1

0 0 5 10 15 20 25 Carapace Length (cm)

Females Males Unsexed

Figure 2: Tail to carapace measurements for female, male and unsexed individuals

Manning River Helmeted Turtle Population Demographics 2018-2019 Surveys 16 14 12 10 8 6

Turtle Frequency 4 2 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Carapace length (cm)

Male Unsexed Female

Figure 3: Graph of the population demographics for the combined survey sites for female, male and unsexed individuals

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5 Discussion 5.1 Turtle reproduction and population demographics 5.1.1 Recruitment From the two autumn season surveys by Redleaf (2018 and 2019), there appear to be recruitment into the turtle population with nearly 30% of turtles caught being immature or maturing individuals. This is much higher than recorded for the Endangered Myuchelys belli from the Murray Darling Basin where immature captures account for about 4% in the catchment, 11% in the catchment and 20% in the (unpublished data, NTLLS). Similarly, our data indicates recruitment into the population across most years because nearly all sizes are represented from small immatures through to large adults of both sexes. 5.1.2 Sex ratios The observed sex ratio of 2:1 in favour of females is an interesting result and warrants further attention. The combined data of Redleaf Environmental and surveys by Spark and Chessman (2018 and 2019) across the Manning River may reveal a different conclusion. However, Chessman (2019) reported the capture of 19 females and 11 males (n = 37 M. purvisi) which indicates a similar bias toward females. We cannot rule out capture bias in the methods employed, however, from the author’s experience all techniques appear to be unbiased for capture between the sexes across many sites and many species of freshwater turtles. 5.1.3 Mating behaviour The courtship and mating behaviour of captive Myuchelys purvisi was recorded by Cann (1998) as occurring in March with a possibility of extending from February to April each year. For the first time during these surveys, we observed M. purvisi copulating in the wild. Three pairs in total were seen copulating underwater at about 2 m depth. On each occasion, the snorkeller was able to capture both the female and male turtles caught in the act. All three pairs were from the Rowleys River at Sites 22 and 23, on the 28th and 29th of March 2019 at 5:30 pm and 10:30 am respectively. 5.2 Threatening processes The following observations and threatening processes for the persistence of M. purvisi should not be viewed as comprehensive as no empirical data were collected regarding the potential threats (e.g., no data were collected on fox predation of nests). These are Redleaf observations only. 5.2.1 Nest predation Feral animals such as foxes and pigs can cause havoc among freshwater turtle populations through predation of nests. Foxes can cause losses of >90% of all nests for a season (Spencer and Thompson 2005; Spencer et al. 2016; Petrov et al. 2018). When this threatening process occurs for a sustained number of years or decades, it can result in the nearly complete loss of natural recruitment into the population. When this happens, the population of turtles in the river contain only the adult turtles with a skewed demographic toward older turtles. Because of the longevity of most freshwater turtles, this can mask the population health until a collapse in turtle abundance as older turtles die through natural or other causes (e.g., deaths from illegal / legal fishing, salt invasion, loss of habitat, disease, climate change) (Bower et al. 2016; Spencer et al. 2018; Van Dyke et al. 2019). Across the Manning River catchment surveys sites assessed by Redleaf Environmental, pigs were ubiquitous with several small groups seen during snorkelling efforts. Their rooting along the stream banks was obvious at most locations. Dingos were also heard and seen at several sites. No foxes or cats were observed; however, they are more than likely present across much of the catchment’s natural areas. Goannas were numerous and observed at about 50 % of the sites. These native species are known to predate freshwater turtle nests (Hamann et al. 2007).

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Without further study into these feral and native predators of turtles and their nests, it is hard to predict the level of impact they are having on the populations of M. purvisi and their habitat. Based on the observed catch of 30% immature turtles across cohorts, these predators may not be affecting M. purvisi populations as significantly as recorded elsewhere. 5.2.2 Eye cataracts Freshwater turtles are known to suffer from a range of physical damage and injuries including eye damage from cataracts and other yet unknown afflictions causing blindness. The Bell’s turtles, Myuchelys belli, from the Murray-Darling Basin’s Namoi River, Gwydir River and Border Rivers catchments have varying rates of blindness with some populations having 10-30% of the captured turtles with cataracts in one or both eyes (Cann 1998; Fielder 2011; Fielder et al. 2015b). The current surveys for M. purvisi revealed two adult female turtles experiencing cloudy eyes or cataracts. This affliction is the first to be recorded for M. purvisi. Little is known about the causes of cloudy eyes and whether these can be revised over time. Some recaptures of M. belli have indicated full recovery years later (Bruce Chessman pers com 2018). Female M. purvisi with cloudy eyes (or cataracts). Captured from the Cooplacurripa River at Cooplacurripa Station (Site 16). There were two adult females with this condition caught here.

5.2.3 Habitat modification Most sites surveyed by Redleaf were in moderate to good condition, with some sites located within national parks or relatively intact landscapes, near pristine. The more modified river reaches were observed in the agriculturally developed areas where cattle grazing and improved pasture management resulted in reduced riparian vegetation, higher levels of silt and sediment on the beds of the streams, erosion and trampling of the banks and eutrophication through elevated nutrient loads from cattle defecation. The unfettered stock access and management of the Cooplacurripa River was of note because of observed (visual only) loss of riparian vegetation, high nutrient loads, high algal growth, high macrophyte growth and extensive erosion of

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Ecology I Environment I Heritage the bed and banks of the river. These modifications have occurred through decades of sustained modification causing morphological changes to the river bed and banks. The main changes include broadening of the river, loss of vegetation cover, reduced pool depths and increased siltation of the river. In contrast, the Rowleys River, Mummel River, Nowendoc River and Bobin Creek provide the most naturally intact instream and riparian habitats across the sites surveyed by Redleaf Environmental. 5.2.4 Competition and hybridisation with Emydura macquarii Only one Emydura macquarii was caught during the surveys by Redleaf Environmental (2018-2019). This was a small adult male turtle from the Nowendoc River. Large numbers (68) were caught by Chessman (2019) in the lower Manning River catchment and extending upstream into its tributaries. The threat to M. purvisi from the introduced E. macquarii are twofold: competition for food and occupying similar habitat niches, and from hybridisation through direct mating between the two species. These threatening processes have already become apparent for the congener species of M. georgesi from the Bellinger River catchment (Georges et al. 2007; Georges et al. 2011; Spencer et al. 2014; Cann et al. 2015; Zhang et al. 2018). A specimen collected by Chessman (2019) appears to show morphological characteristics which may refer to a hybrid individual.

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6 Conservation considerations The two autumn surveys (2018 and 2019) of the endangered Manning River Helmeted Turtle, Myuchelys purvisi, has provided much needed data on the extent and demographics for this species. From the surveyed sites, the Mummel River, Rowley River and Bobin Creek sites provided the most pristine aquatic environments for M. purvisi populations and have potential to be ‘reference’ sites. The Cooplacurripa River is heavily impacted from extensive catchment clearing and unfettered access to large herds of cattle. The river itself is in a moderate condition overall and there are likely to be good numbers of M. purvisi present. The Nowendoc River was a large stream with numerous deep and extensive waterholes. On this survey, the capture effort appeared to be lower than expected given the available habitat. Potential threatening processes have been identified in this report and elsewhere (Chessman 2019). There does appear to be negative impacts from heavy grazing on the riparian and aquatic environments but other threatening processes remain uncertain. For example, it remains unknown on how much foxes are impacting on the recruitment rates of the M. purvisi populations. This is a major threatening process for other freshwater turtles (e.g., Myuchelys bellii) (Fielder et al. 2015a). The long-term impact from the introduced Emydura macquarii is cause for alarm and should be addressed in both policy and community awareness to allow for suitable solutions to be investigated and advanced before it is too big of a management issue to deal with. The relatively low numbers (but ever increasing in recruitment and size) potentially offers an opportunity to address it now rather than later when resources required will be substantially greater and more costly. 6.1 Future management actions Based on the information collected so far, the following recommendations are provided: • Continue to gather base line information on the population demographics to provide a better understanding of the overall population size and structure (immature, mature turtle and sex ratios etc.); • Continue to target new areas for M. purvisi surveys or areas where only limited effort has been done; • Continue to undertake mark recapture surveys to provide long-term trend data on M. purvisi populations (i.e., reference sites); • Undertake dietary analysis across the life history size classes. This information would provide insight to the food resources required to maintain healthy individuals. Other species in the Myuchelys genus have suffered from malnutrition and mystery viruses leading to a near extinction event for M. georgesi (see Spencer et al. 2018); • Undertake genetic research to determine if the Emydura macquarii (suspected to be an introduction to the Manning River Catchment) has hybridised with M. purvisi. This is a recognized threat for M. georgesi (Spencer et al. 2014); and • Research the reproductive biology of M. purvisi including nesting habitat assessments, fox predation rates and fecundity assessments.

The potential threatening processes for the M. purvisi lend themselves to the Saving our Species Program (SoS) management streams of: • Landscape-managed species: threatened plants and animals that need landscape scale conservation projects; or • Data-deficient species: threatened species that we need to know more about before we can secure them in the wild.

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7 References Bower, D., Scheltinga, D., Clulow, S., Clulow, J., Franklin, C., and Georges, A. (2016). Salinity tolerances of two Australian freshwater turtles, Chelodina expansa and Emydura macquarii (Testudinata: Chelidae). Conservation Biology 4. doi:10.1093/conphys/cow042

Cann, J. (1998). ‘Australian Freshwater Turtles’. (Beaumont Publishing: Singapore.)

Cann, J., Spencer, R.-J., Welsh, M., and Georges, A. (2015). Myuchelys georgesi (Cann 1997) – Bellinger River Turtle. Chelonian Conservation and Biology. doi:10.3854/crm.5.091.georgesi.v1.2015

Chessman, B. C. (2019). Conservation program for the Manning River helmeted turtle – survey and monitoring. Report on turtle trapping in 2018-19. Chessman Ecology prepared for the NSW Office of Environment and Heritage.

Fielder, D., Georges, A., and Chessman, B. (2015a). Myuchelys bellii (Gray 1844) – Western Saw-shelled Turtle, Bell’s TurtleRhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs 5, 1–7. doi:10.3854/crm.5.088.bellii.v1.2015

Fielder, D. P. (2011). Population ecology, ecophysiology, phylogenetics and taxonomy of the threatened western sawshelled turtle, Myuchelys bellii, from the Murray-Darling Basin of . PhD Thesis, Environmental and Rural Sciences, University of New England Armidale.

Fielder, D. P., Limpus, D. J., and Limpus, C. J. (2015b). Reproduction and population ecology of the vulnerable western sawshelled turtle, Myuchelys bellii, in the Murray–Darling Basin, Australia. Australian Journal of Zoology 62, 463–476.

Georges, A., Spencer, R., Welsh, M., Shaffer, H., Walsh, R., and Zhang, X. (2011). Application of the precautionary principle to taxa of uncertain status: The case of the Bellinger River turtle. Endangered Species Research 14, 127–134. doi:10.3354/esr00350

Georges, A., Walsh, R., Spencer, R. J., Welsh, M., and Shaffer, H. B. (2007). The Bellinger Emydura. Challenges for Management. Report to NSW National Parks and Wildlife Service, Sydney. Institute for Applied Ecology, University of Canberra, Canberra.

Hamann, M., Schauble, C. S., Limpus, D. J., Emerick, S. P., and Limpus, C. J. (2007). Management Plan for the conservation of Elseya sp. [Burnett River] in the Burnett River Catchment. (Queensland Environmental Protection Agency: Brisbane).

Petrov, K., Stricker, H., Van Dyke, J. U., Stockfeld, G., West, P., and Spencer, R.-J. (2018). Nesting habitat of the broad-shelled turtle (Chelodina expansa). Australian Journal of Zoology. Available at: https://doi.org/10.1071/ZO17061

Redleaf Environmental (2018). Manning River Helmeted Turtle 2018 Autumn Survey Report. Redleaf Environmental prepared for the NSW Office of Environment and Heritage.

Spencer, R. J., and Thompson, M. B. (2005). Experimental analysis of the impact of foxes on freshwater turtle populations. Conservation Biology 19, 845–854.

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Spencer, R.-J., Georges, A., Lim, D., Welsh, M., and M. Reid, A. (2014). The risk of inter-specific competition in Australian short-necked turtles. Ecological Research 29, 767–777. doi:10.1007/s11284-014-1169- 7

Spencer, R.-J., Van Dyke, J., Petrov, K., Ferronato, B., Mcdougall, F., Austin, M., Keitel, C., and Georges, A. (2018). Profiling a possible rapid extinction event in a long-lived species. Biological Conservation 221, 190–197.

Spencer, R.-J., Van Dyke, J., and Thompson, M. (2016). The ‘Ethological Trap’: Functional and numerical responses of highly efficient invasive predators driving prey extinctions. Ecological Applications 26. doi:10.1002/eap.1375

Van Dyke, J., –J. Spencer, R., B. Thompson, M., Chessman, B., Howard, K., and Georges, A. (2019). Conservation implications of turtle declines in Australia’s system. Scientific Reports 9. doi:10.1038/s41598-019-39096-3

Zhang, J., S. Finlaison, D., Frost, M., Gestier, S., Gu, X., Hall, J., Jenkins, C., Parrish, K., Read, A., Srivastava, M., Rose, K., and D. Kirkland, P. (2018). Identification of a novel nidovirus as a potential cause of large scale mortalities in the endangered Bellinger River snapping turtle (Myuchelys georgesi). PLoS ONE 13, e0205209. doi:10.1371/journal.pone.0205209

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Appendix A – Site photos Site Photos of the survey sites 11. Cooplacurripa River, Top Station Mostly shallow with several small pools to 1.5 m. A shaded stream with riparian vegetation present. Evidence of stock access through bank trampling. Stream had a small flow through it with high turbidity preventing snorkelling as a capture method.

12. Mummel River, Cooplacurripa Station Trapping site with several deeper pools to 1.8 m. Water clarity was good with intact riparian zone vegetation.

13. Mummel River, Cooplacurripa Station Snorkel location.

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Site Photos of the survey sites 14. Mummel River, Cooplacurripa Station Snorkel location.

15. Mummel River, Cooplacurripa Station Snorkel location.

16. Cooplacurripa River, Cooplacurripa Station Thin strip of riparian vegetation occurs here. The river had large levels of algae and macrophyte growth instream due from limited shading of the stream and eutrophication from unfettered cattle access.

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Ecology I Environment I Heritage

Site Photos of the survey sites 19. Rowleys River, Strike-A-Light pump hole. This section of the river was in a near pristine condition with a rocky bed and banks and with excellent water clarity. The waterhole itself was being impacted through stock and domestic pumping 24/7. This section was up to 1.5 m deep.

22. Rowleys River, Terranbanella Station homestead. Wide stream with several waterholes to 3.5 m. Water clarity was moderate. Shallow sections with extensive algal and macrophyte growth making snorkelling difficult. One pair were observed mating underwater at a depth of about 2 m, and subsequently caught (in the act) by the snorkellers.

23. Rowleys River, Strike-A-Light at its northern boundary. Near pristine river reach with large deep waterholes. Water clarity was excellent here. Caught 16 M. purvisi in this stretch. Two pairs were observed mating underwater at a depth of about 2 m, and subsequently caught (in the act) by the snorkellers.

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Site Photos of the survey sites 25. Bobin Creek, Les McKensie place. Pristine stream environment except for infestation of small and large leaved privet in the riparian vegetation. Cristal clear water (cold ~15 degrees) with areas of leaf litter covering the creek bed providing habitat for M. purvisi. Mostly long shallow stream reaches interspersed with small deeper waterholes (to about 1.5 m). Three large waterholes to 3.5 m occur 1 km from each other.

28. Dingo Creek, Dingo Bend. Thin riparian strip along each side of the banks. Adjacent land use is improved pasture paddocks and cattle grazing. There wasn’t a waterhole deeper than 1.5 m. Mostly wide shallow stretches. The water clarity was moderate. Very cold water (~15 degrees).

29. Mummel River, Peter Fotheringham station. Large deep waterholes present. High levels of turbidity prevented snorkelling here.

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Ecology I Environment I Heritage

Site Photos of the survey sites 30. Rowleys River, upstream of Terranbanella homestead. A relatively intact landscape with excellent instream habitat.

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Incidental records and photos

Fyke net in position at Cooplacurripa River, near the homestead.

Shannon Michael with his snorkelling catch, Cooplacurripa Station near the homestead.

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Ecology I Environment I Heritage

Snorkel catch of Myuchelys purvisi at Rowleys River (site 23).

Snorkel catch of Myuchelys purvisi at Rowleys River (site 23).

Releasing a male M. purvisi turtle into the Mummel River (site 12).

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Ecology I Environment I Heritage

Dr Darren Fielder B.App.Sci, PhD mobile 0407 234 986 email [email protected] address PO Box 3564 Toowoomba Queensland 4350 www.Redleafenv.com.au

Our Footprint for Future Generations

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