Threatened Monitor Lizard and Bat Survey of the Finniss River Prepared for: Hydrobiology Prepared by: EcOz Environmental Consultants 2 015 1. www.ecoz.com.au This page has been intentionally left blank Client: Hydrobiology ii Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River Document Control Record Document Code: EZ15036-C0301-EST-R-0002 Catalogue Number: 31590 Project Manager: Dane Trembath Author(s): Dane Trembath Approved by: Ray Hall Approval date: 23 July 2015 DOCUMENT HISTORY Version Issue Date Brief Description Reviewer/Approver 1.A 10 June 2015 Report preparation by authors D. Trembath 1.B 15 July 2015 EcOz review C. Brady 1.C 20 July 2015 EcOz comments incorporated D. Trembath 1.D 22 July 2015 Draft sent to client 1.0 23 July 2015 Final report sent to client Recipients are responsible for eliminating all superseded documents in their possession. EcOz Pty Ltd. ABN: 81 143 989 039 Telephone: +61 8 8981 1100 Winlow House, 3rd Floor Facsimile: +61 8 8981 1102 75 Woods Street Email: [email protected] DARWIN NT 0800 Internet: www.ecoz.com.au GPO Box 381, Darwin NT 0800 Client: Hydrobiology iii Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River RELIANCE, USES and LIMITATIONS This report is copyright and is to be used only for its intended purpose by the intended recipient, and is not to be copied or used in any other way. The report may be relied upon for its intended purpose within the limits of the following disclaimer. This study, report and analyses have been based on the information available to EcOz Environmental Consultants at the time of preparation. EcOz Environmental Consultants accepts responsibility for the report and its conclusions to the extent that the information was sufficient and accurate at the time of preparation. EcOz Environmental Consultants does not take responsibility for errors and omissions due to incorrect information or information not available to EcOz Environmental Consultants at the time of preparation of the study, report or analyses. Client: Hydrobiology iv Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River This page has been intentionally left blank Client: Hydrobiology v Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River Table of Contents 1 Introduction ..................................................................................................................................................1 1.1 Background ..........................................................................................................................................1 1.2 Scope ...................................................................................................................................................1 2 Methods .......................................................................................................................................................2 2.1 Survey Design ......................................................................................................................................2 3 Results .........................................................................................................................................................5 3.1 Aquatic Monitors...................................................................................................................................5 3.2 Micro Bats ............................................................................................................................................5 3.3 Incidental observations ........................................................................................................................5 4 Discussion ...................................................................................................................................................9 4.1 Threatened Species .............................................................................................................................9 4.2 Bat Survey ......................................................................................................................................... 12 4.3 Faunal Diversity ................................................................................................................................. 12 4.4 Summary and Recommendations ..................................................................................................... 12 5 References ............................................................................................................................................... 13 Tables Table 1. Merten’s Water Monitors (Varanus mertensi) observations during the 2015 surveys. .......................6 Table 2. Mertens Water Monitors (Varanus mertensi) observations in the 2014 and 2015 Surveys. ................6 Figures Figure 1. Goanna and Bat Sampling Sites at the Upper Finniss River. ............................................................3 Figure 2. Basking Merten’s Water Monitors (Varanus mertensi)) observed during the survey. .........................4 Figure 3. Threatened species observed during the 2104 and 2015 surveys. ...................................................7 Figure 4. Camera trap photos of Mertens Water Monitor (Varanus mertensi) (Top) and Mitchell’s Water Monitor (Varanus mitchelli) (Bottom) from the 2015 surveys. ............................................................................8 Figure 5. Partridge Pigeon (Geophaps smithii) records from within 10 km of the rum Jungle Mine. .............. 11 Appendices Appendix A – Fauna records recorded during the 2015 field surveys of the Finniss River. Appendix B Bat Call Identification from Finniss River, Northern Territory. Acknowledgements Thanks to the staff of the Rum Jungle Rehabilitation Team for providing access to the sites and informing the landholders of our fauna surveys. Client: Hydrobiology vi Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River 1 Introduction 1.1 Background A previous series of surveys in 2014 confirmed that the Upper Finniss River and East Branch of the Finniss River are inhabited by Merten’s Water Monitor (Varanus mertensi) (EcOz 2014a;b). Additionally there was also some evidence that the Bare-rumped Sheath-tailed Bat (Saccolaimus saccolaimus) may be present at one site on the Upper Finniss River (EcOz 2014). As part of plans to rehabilitate the site, Hydrobiology (2013b) recommended “a detailed survey of all culturally significant aquatic reptiles species downstream of the former Rum Jungle Mine to gain an understanding of species abundance and secondly to determine distribution in relation to the former Rum Jungle Mine be conducted”. This study was commissioned to follow this recommendation. 1.2 Scope The objective of this report is to discuss the findings of surveys targeting aquatic monitors and a threatened bat in the riparian zone of the Finniss River in the vicinity of the Rum Jungle Mine. This assessment is a component of an on-going monitoring program to assess biological impairment in the riparian zone associated with the Rum Jungle Mine. Client: Hydrobiology 1 Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River 2 Methods 2.1 Survey Design 2.1.1 Site layout The survey was conducted within the vicinity of eight historical water sampling sites downstream and upstream of the former Rum Jungle Mine site (Figure 1). 2.1.2 Aquatic monitors Active searching Survey sites were actively searched during the day when goannas were the most active. This involved: Actively searching on foot at each site during both seasons. Surveying by boat during the dry season along each bank of the entire stretch of each site and consisted of visual searches for basking monitors (Figure 2) as described in Doody et al. (2006). Recording tracks where they could be confidently attributed to species. Camera traps Two motion-activated camera traps (Keep Guard KG-690) were installed at each of the eight survey sites for seven weeks. Cameras were set up in areas where fauna were considered likely to occur, for example pointing at banks used by Merten’s Water Monitor as basking platforms. 2.1.3 Microbats Bat species were surveyed using two high-frequency Anabat bat detectors, which were set to record overnight for three nights at G204, where Saccolaimus sp. Was recorded in previous a survey (EcOz 2014)) Recorded bat calls were sent to bat expert, Kyle Armstrong (Specialised Zoological) for identification (Appendix B). 2.1.4 Opportunistic observations Opportunistic observations were made whilst in the study area. Aquatic monitors were recorded in an ‘incidentals’ list. All other vertebrate fauna identified at each of the eight sites was recorded. Nomenclature Nomenclature and classification of fauna species refers to the Classification of Wildlife of the NT – January 2011 (DLRM). Survey limitations The results of these surveys are only a snapshot in time, and do not allow for temporal variations or species migrations. Environmental factors affect capture rates (Read & Moseby 2001). Planning logistics for fauna surveys such as this around specific environmental conditions is very difficult particularly with the compromise between access (during the dry season) and times when species are more active (e.g. during the build-up/wet season). Client: Hydrobiology 2 Doc Title: Threatened Monitor Lizard and Bat Survey of the Finniss River Figure 1. Goanna and Bat Sampling Sites at the Upper Finniss River. Client: Hydrobiology