Sass Sassandmetzler Frogs-1
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HERPETOFAUNA TEXT 41-1v4_HERPETOFAUNA TEXT 35-1 2/06/13 9:14 PM Page 9 THE FROG DIVERSITY OF THE PAMBULA RIVER FLOODPLAIN IN SOUTH- EASTERN NEW SOUTH WALES Steve Sass 1,2,3 , Linda Sass 1 & Caroline Metzler 1 1EnviroKey, PO Box 7231, Tathra, NSW 2550. 2Institute for Land, Water and Society, Charles Sturt University, Wagga Wagga, NSW 2678. 3Email: [email protected] INTRODUCTION itage Reserve Trust for the purpose of conser - vation and restoration of a previously agricul - The Bega Valley local government area (LGA) tural dominant landscape. This area is known covers an area of approximately 6,052 as 'Panboola'. square kilometers and comprises the well- known coastal towns of Bermagui, Tathra, With little known of the frog diversity of the Merimbula and Eden. The LGA includes Pambula River floodplain, the aim of this almost 106 kilometres of coastline and to the manuscript is to document the frog species west, reaches the higher peaks of the Great present at 'Panboola', including a review of Dividing Range reaching beyond 1000 m previous records and provision of a systemat - above sea level. This fluctuation in topogra - ic survey. Discussion is also provided on the phy has led to the development of diverse likelihood of occurrence for unrecorded coastal floodplains, the majority now support - species. ing intensive agricultural activities. METHODS A recent literature review revealed that 26 frog species have been previously recorded in Study Area the LGA confirming a relatively high amphib - ian diversity (EnviroKey, 2011). However, the 'Panboola' is located on the NSW far south majority of past studies and previous surveys coast. It is broadly flanked by Ben Boyd are from within the forests of national parks, National Park to the east, Pambula River to state forests and nature reserves (Daly, 1998, the south, the Princes Highway and agricul - 2007; Daly et al., 2002; Daly & Senior, 2001, tural land to the west and the town of 2003; Lemckert et al. , 1997, 1998; Lunney & Pambula to the north (Figure 1). Barker, 1986; NGH 2008; Penman, 2005; Desktop Analysis Penman et al ., 2004, 2006, 2008) highlight - ing a paucity of data on frogs relative to other A desktop analysis was conducted to gain an land tenures. Further, less than 3% of all frog understanding of the frog species previously records within the LGA come from coastal recorded within the general locality of 'Pan - floodplains despite frog communities being boola'. This comprised searches of the NSW considered an important component of flood - BioNet database and records of the Aus - plain biota (Healey et al. , 1997). tralian Museum focusing on a 10 km radius from the centre point of the study area. The Pambula River floodplain comprises a series of diverse estuarine and freshwater Field Surveys wetlands which are now, in many parts, dom - Six survey sites were established at 'Panboola' inated by agricultural activities. A 77 hectare with the aim of including the full range of portion of the floodplain is now managed by habitats within the study area. This approach the Management Committee of Pambula had the objective of detecting the full diversi - Wetlands and Heritage Project Inc. in con - ty of frog species that could occur within the junction with the Pambula Wetlands and Her - study area. Two sites were established within Herpetofauna 41 (1-2) 2011 Page 9 HERPETOFAUNA TEXT 41-1v4_HERPETOFAUNA TEXT 35-1 2/06/13 9:14 PM Page 10 Figure 1. Location of the six survey sites for this study. permanent freshwater wetlands (Tips Bill - have supported populations of this species in abong, Waterbird Sanctuary 1), two sites the past (DECC, 2005; NPWS, 1999; White & within ephemeral freshwater wetlands (Corri - Pyke, 1996). Calls of this species were played dor, Waterbird Sanctuary 2), one site within for a period of two-minutes. This was fol - estuarine coastal saltmarsh (Saltmarsh) and lowed by a further two-minute listening one site within the riparian vegetation flank - period. ing the Pambula River (Riparian). Figure 1 Active searches and spotlighting were then details the location of the six survey sites. conducted over 40-person minutes and call Nocturnal surveys for frogs were undertaken recognition was also used to identify any frog at each of the six sites on three occasions species calling. Species heard or observed (27–28 October and 7–8 December 2010). within a 50 m radius of the site were record - This resulted in a total of 18 surveys and a ed with an approximation of their abundance total survey effort of approximately 13.2 made by estimating the numbers of frogs hours. A single frog survey comprised of a calling. This is represented by a ranked scale combination of listening for frog calls, spot - of between 1 and 5 (1 = <10 frogs, 2 = lighting, active searching of habitat where 10–30 frogs, 3 = 30–50 frogs, 4 = 50–100 possible and call playback of threatened frog frogs, 5 = >100 frogs). species within a 50 m radius of the site Weather conditions at the time of the surveys marker. At the commencement of each frog and rainfall within the preceding week were survey, a two-minute listening period was considered conducive to detecting frogs. Tem - undertaken to record any species heard peratures and rainfall data were drawn from calling. Call playback was chosen for the Merimbula Airport weather station (5 km to threatened Green and Golden Bell Frog the north) for the October and December (Litoria aurea ) given that 'Panboola' is likely to surveys. During the October survey, tempera - Page 10 Herpetofauna 41 (1-2) 2011 HERPETOFAUNA TEXT 41-1v4_HERPETOFAUNA TEXT 35-1 2/06/13 9:14 PM Page 11 tures ranged between 6° C (minimum) and Protocols for the control of disease were 19.2° C (maximum) with 21 mm of rainfall in the implemented at all times as outlined within 7 days prior to the survey. During the December 'Hygiene Protocols for the control of disease survey, temperatures ranged between 17.1° C in frogs' (DECC, 2008b). Nomenclature (minimum) and 24.9° C (maximum) with 107 adopted for this study follows Tyler and Knight mm of rainfall in the 7 days prior to the (2009) with the exception of Litoria dentata survey. which is more commonly referred to as the Bleating Tree Frog. Table 1. Frog species, their legal status and the number of individuals recorded within a 10 km radius of 'Panboola'. Data from DECCW NSW Atlas of Wildlife and Australian Museum records (P = Protected, V = Vulnerable, E = Endangered, TSC = NSW Threatened Species Conservation Act 1995 , EPBC = Environment Protection and Biodiversity Conservation Act 1999 ). Common name Scientific name Legal No. of status individuals Common Froglet Crinia signifera P 59 Giant Burrowing Frog Heleioporus australiacus V TSC 7 V EPBC Eastern Banjo Frog Limnodynastes dumerilii P3 Striped Marsh Frog Limnodynastes peronii P 24 Haswell's Froglet Paracrinia haswelli P3 Bibron's Toadlet Pseudophryne bibronii P3 Tyler's Toadlet Uperoleia tyleri P4 Green and Golden Bell Frog Litoria aurea E TSC 6 V EPBC Blue Mountains Tree Frog Litoria citropa P1 Bleating Tree Frog Litoria dentata P2 Ewing's Tree Frog Litoria ewingii P 48 Eastern Dwarf Tree Frog Litoria fallax P2 Jervis Bay Tree Frog Litoria jervisiensis P6 Lesueur's Frog Litoria lesueuri P 12 Peron's Tree Frog Litoria peronii P 98 Narrow Fringed Frog Litoria nudidigitus P 21 Verreaux's Tree Frog Litoria verreauxii P 20 Herpetofauna 41 (1-2) 2011 Page 11 HERPETOFAUNA TEXT 41-1v4_HERPETOFAUNA TEXT 35-1 2/06/13 9:14 PM Page 12 RESULTS Species Abundance Desktop Analysis The highest level of abundance recorded was for Common Froglet ( Crinia signifera ) at The desktop analysis revealed a total of 17 WBS1 during the October survey (Table 3) and species of frog and a total of 319 records Bleating Tree Frog ( Litoria dentata ) at Corridor within a 10 km radius of 'Panboola' (Table 1). during the December survey (Table 4). This includes two species listed under the schedules of the NSW Threatened Species Relative abundance was higher during the Conservation Act 1995 and the Common - December surveys in comparison to the wealth Environment Protection and Biodiversity October surveys. At Corridor, both diversity Conservation Act 1999: the Giant Burrowing and abundance was notably different ranging Frog ( Heleioporus australiacus ) and the Green from no frog species in October to six frog and Golden Bell Frog ( Litoria aurea ). species present during December, with L. dentata the most abundant with 50–100 indi - Field Surveys viduals calling (Table 4). Field surveys during this study revealed a total Species Distribution of eleven frog species (Table 2). Some frog species were recorded at all, or the When pooling data from each site for the majority of the survey sites during this study. three surveys, six frog species were recorded Crinia signifera were recorded at every survey at each of the sites Corridor, Saltmarsh, Tips site while Striped Marsh Frog ( Limnodynastes Billabong and Waterbird Sanctuary 1 (WBS1) peronii ), Peron's Tree Frog ( Litoria peronii ) and (Table 3). The Riparian site had the lowest Verreaux's Tree Frog ( Litoria verreauxii ) were frog species diversity with only two species recorded at all survey sites with the exception recorded. of the Riparian site. Table 2. Frog species recorded on the Panboola River Floodplain (calling or observed). (C= Corridor, R = Riparian, S = Saltmarsh, T = Tips Bill - abong, WBS = Waterbird Sanctuary). Common Name Scientific Name CRSTWBS1 WBS2 Common Froglet Crinia signifera **** * * Eastern Banjo Frog Limnodynastes dumerilii * Striped Marsh Frog Limnodynastes peronii ***** Spotted Grass Frog Limnodynastes tasmaniensis * Bleating Tree Frog Litoria dentata ** Ewing's Tree Frog Litoria ewingii ** Jervis Bay Tree Frog Litoria jervisiensis * Peron's Tree Frog Litoria peronii ***** Verreaux's Tree Frog Litoria verreauxii ***** Bibron's Toadlet Pseudophryne bibronii * Smooth Toadlet Uperoleia laevigata * Page 12 Herpetofauna 41 (1-2) 2011 HERPETOFAUNA TEXT 41-1v4_HERPETOFAUNA TEXT 35-1 2/06/13 9:15 PM Page 13 Conversely, three species of frog were record - distribution across 'Panboola' was no different.