Growling Grass Frog Conservation Management Plan

Transcription

1 Armstrong Creek North East Industrial Precinct Growling Grass Frog Conservation Management Plan MAY

2 Table of Contents Summary Introduction Project Information Study area Background Growling Grass Frog Litoria raniformis Conservation status Habitat requirements Threatening Processes Results Habitat within the Study Area Occurrence of Growling Grass Frog within the Study Area and Surrounds Potential Impacts Hydrology and Water Quality Human Access Weeds Dog and Cat Ownership Exotic Predators Habitat Protection Habitat Enhancement Water Quality Feral and domestic animal control Mitigation Measures Habitat Protection Habitat Enhancement Water Quality Feral and domestic animal control Monitoring of Growling Grass Frog Habitats Created wetlands Potential Movement Corridors Population Monitoring Potential Habitat Improvements Opportunities for Habitat Creation and Enhancement in the Barwon River and Floodplain Wetland Design and Habitat Enhancement Artificial Wetlands for the Management of Stormwater...19 Conclusion...21 Figures...22

3 Appendices...26 References...34 Tables Table A1.1. Rare or threatened categories for listed Victorian taxa Table A1.2. Defining Ecological Significance...28 Table A1.3. Defining Site Significance...30 Table A1.4. Defining Vegetation Condition Table A1.5. Defining Habitat Quality...32 Table A2.1. Plant species recommended for wetland vegetation...33

4 Acknowledgments We thank the following people for their contribution in the project. Warwick Maughan (Nu Vue Property Group) and Nicole Donnison (CPG Australia Pty Ltd) for project and site information; Alex Wilks (TGM) for stormwater infrastructure information; Burke Renouf (Environment and Natural Resources Unit, City of Greater Geelong) for biodiversity management plan information; Donna Burns (Department of Sustainability and Environment) for Precinct Structure Plan advice; Daniel Jerabek for a recent Growling Grass Frog record; Landholders within the study area for general site information; and, Department of Sustainability and Environment for access to the data on the Flora Information System and Atlas of Victorian Wildlife. The following Ecology Partners Pty. Ltd. employees contributed to the preparation of the report: Clio Gates Foale, Aaron Organ and Andrew Hill Copyright Ecology Partners Pty. Ltd. This document is subject to copyright and may only be used for the purposes for which it was commissioned. The use or copying of this document in whole or part without the permission of Ecology Partners Pty. Ltd. is an infringement of copyright. Disclaimer Although Ecology Partners Pty. Ltd. have taken all the necessary steps to ensure that an accurate document has been prepared, the company accepts no liability for any damages or loss incurred as a result of reliance placed upon either the report or its content.

5 SUMMARY Ecology Partners Pty Ltd was engaged by Nu Vue Property Group, on behalf of Capella Pacific, to prepare a Conservation Management Plan for the nationally threatened Growling Grass Frog Litoria raniformis. Although the species was not detected during recent targeted surveys, this document is intended as a precautionary measure as the Growling Grass Frog has been recorded in the local area, it is a highly mobile species and potentially suitable habitat is present within the study area. The study area is the North East Industrial Precinct (NEIP) within the Armstrong Creek Growth Area and the immediately adjacent low-lying floodplain of the Barwon River, located approximately five kilometres southeast of the Geelong CBD, at Marshall, Victoria. The extent of the study area is approximately 230 hectares and is situated immediately east of Barwon Heads Road, to the south and the west of the Barwon River, and to the north of Reserve Road. The Conservation Management Plan (CMP) has been prepared in response to recommendations outlined in the previous targeted survey report undertaken within parts of the study area and from discussions with the Department of Sustainability and Environment (DSE), in regards to the preparation of a Precinct Structure Plan (PSP). It provides detailed information relating to the conservation and future management of the Growling Grass Frog, as a precautionary measure, to ensure the species can persist within suitable habitats, such as the Barwon River and floodplain in the future. A monitoring program is also proposed in the event that the species is discovered on-site during any proposed works. The most important element for the effective implementation of the management plan is the ongoing commitment and coordination from the land developers/owners and relevant agencies, such as City of Greater Geelong, Parks Victoria, Corangamite Catchment Management Authority and DSE. Similarly, there needs to be continual communication between the proponent, referral authorities and specialist consultants experienced in undertaking monitoring and management of the Growling Grass Frog and its habitats. The plan will be undertaken during construction and for two years after construction. Provided that construction, and on-going management and monitoring of the site are in accordance with recommendations provided in this plan, there is likely to be a net improvement in habitat quality on the site for fauna, including the Growling Grass Frog.

6 1 INTRODUCTION 1.1 Project Information Ecology Partners Pty Ltd was engaged by Nu Vue Property Group, on behalf of Capella Pacific, to prepare a Conservation Management Plan for the nationally significant Growling Grass Frog Litoria raniformis. Although the species was not detected during targeted surveys (Ecology Partners Pty. Ltd. 2009), this document is intended as a precautionary measure as the Growling Grass Frog has been recorded in the local area, is highly mobile and potentially suitable habitat occurs within the study area. The Conservation Management Plan (CMP) has been prepared in response to recommendations outlined in the previous targeted survey report undertaken within the study area (Ecology Partners Pty. Ltd. 2009) and from discussions with Donna Burns (DSE) in regards to the preparation of a PSP. It provides detailed information relating to the conservation and future management of the Growling Grass Frog, as a precautionary measure, to ensure the species can persist within suitable habitats, such as the Barwon River and floodplain in the future. A monitoring program is also proposed in the event that the species is discovered on-site during any proposed works. 1.2 Study area The study area is the North East Industrial Precinct (NEIP) within the Armstrong Creek Growth Area and the immediately adjacent low-lying floodplain of the Barwon River, located approximately five kilometres southeast of the Geelong CBD, at Marshall, Victoria (Figure 1). The extent of the study area is approximately 230 hectares and is situated immediately east of Barwon Heads Road, to the south and the west of the Barwon River, and to the north of Reserve Road. The study area contains areas of both remnant indigenous vegetation with a high cover of native plant species, and highly modified paddocks comprising introduced pasture grasses and weeds, and planted strips of vegetation. According to DSE s Biodiversity Interactive Map ( the study area is within the Otway Plain bioregion. The majority of the Otway Plain bioregion extends from the Bellarine Peninsula in the east to Warrnambool in the west. The study area is located within the region under the management of the Corangamite Catchment Management Authority, within the Barwon River Basin Catchment (

7 2 BACKGROUND 2.1 Growling Grass Frog Litoria raniformis Conservation status The Growling Grass Frog is commonly known by several other names; Warty Bell Frog, Southern Bell Frog, Warty Swamp Frog and Green and Golden Frog. The species is listed as vulnerable nationally (Tyler 1997) and endangered in Victoria (DSE 2007). It is also listed as a threatened taxon under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 and the Victorian Flora and Fauna Guarantee Act A draft Flora and Fauna Guarantee Action Statement (Robertson 2003) and a draft National Recovery Plan have been development for the species. Overall, the species is of national conservation significance. Although formally widely distributed across south eastern Australia, including Tasmania (Littlejohn 1963, 1982; Hero et al. 1991), the species has declined markedly across most of its former range. The decline has been most evident over the past two decades and in many areas, particularly in south and central Victoria, populations have experienced apparent declines and local extinctions (AVW; Mahoney 1999; A. Organ pers. obs) Habitat requirements This species is largely associated with permanent or semi-permanent still or slow flowing water bodies (i.e. streams, lagoons, farm dams and old quarry sites) (Hero et al. 1991; Barker et al. 1995; Cogger 1996; Ashworth 1998). Frogs can also utilise temporarily inundated water bodies for breeding purposes provided they contain water over the breeding season (Organ 2003). Based on previous investigations there is a strong correlation between the presence of the species and key habitat attributes at a given water body. For example, the species is typically associated with water bodies supporting extensive cover of emergent, submerged and floating vegetation (Robertson et al. 2002, Organ 2004, 2005a). Emergent vegetation provides basking sites for frogs and protection from predators, while floating vegetation provides suitable calling stages for adult males, and breeding and oviposition (egg deposition) sites. Terrestrial vegetation (grasses, sedges), rocks and other ground debris around wetland perimeters also provide foraging, dispersal and over-wintering sites for frogs. Water bodies supporting the above mentioned habitat characteristics and those that are located within at least metres of each other, are more likely to support a population of Growling Grass Frogs, compared to isolated sites lacking important habitat features. Recent studies have revealed that the spatial orientation of water bodies across the landscape is one of the most important habitat determinants influencing the presence of the species at a given site (Robertson et al. 2002; Heard et al. 2004a, 2004b). For example, studies have shown there is a positive correlation between the presence of the species and the distance of freestanding water bodies to another occupied site.,

8 This is comparable to the spatial dynamics of many amphibian populations, including the closely related Green and Golden Bell Frog Litoria aurea (Hamer et al. 2002) Threatening Processes Causes of the decline of the Growling Grass Frog are not fully understood. However, factors that are likely to have contributed to the decline include habitat loss, fragmentation and degradation of habitat (such as land clearing for agriculture and urban development), altered flooding regimes of natural water bodies, predation on eggs and tadpoles by introduced fish, salinisation, chemical pollution of water bodies by fertilisers and pesticides, and infection by the amphibian chytrid fungus (Hamer et al. 2004; White and Pyke 1996). (

9 3 RESULTS 3.1 Habitat within the Study Area Habitat quality at all waterbodies within the study area have been assessed previously (Ecology Partners Pty. Ltd. 2008, 2009). Barwon River is a large watercourse dominated by an open water channel, supporting emergent macrophytes such as Cumbungi Typha spp. and Common Reed Phragmites australis, up to two metres high along the channel fringe. The river contains a variable cover of floating and submerged vegetation, primarily along the stream edges. Native sedges and grasses are present along the river banks, together with introduced pasture grasses. Within the study area, several scattered remnant trees are present along the river banks; although along either side of the stream banks native trees (e.g. River Red-gums) have been planted. Planted shrubs, native grasses and other indigenous vegetation has been also been planted along the river. Barwon River provides moderate quality breeding and dispersal habitat for Growling Grass Frog. Several artificial drainage lines and farm dams occur within the study area, and have been constructed for use as stock watering points, water supply or as irrigation channels. Although the drainage lines are highly modified, lacking key habitat features, some of them do support areas of dense aquatic vegetation such as Common Reed and other low-growing sedges and aquatic plants. These narrow, linear habitats are likely to be ephemeral in nature and areas surrounding the drainage lines are dominated by introduced grasses and weeds, which appear to be slashed regularly. The three small farm dams provide poor quality habitat for Growling Grass Frog (Figure 3), as they contain little fringing habitat and were dry at the time of the assessment. The inside wall of the large dam in the north is covered by old car tyres, and also has little fringing habitat, and provides poor to moderate quality habitat for Growling Grass Frog (Figure 3). There are several small shallow depressions (natural and artificial) on the floodplain, which consist of exotic and native plant species, and these areas are likely to hold water periodically. Areas surrounding a dam on the floodplain are highly modified and dominated by exotic grasses. Based on the current habitat conditions present at these sites they do not provide key habitat requirements for Growling Grass Frog. 3.2 Occurrence of Growling Grass Frog within the Study Area and Surrounds Despite detailed survey during suitable conditions for detecting the species, Growling Grass Frog was not recorded during the current surveys (Ecology Partners 2009). There are two documented records of Growling Grass Frog from the local area (AVW). One of these records (1997) is from approximately two kilometres south-east of the study area, while the other (1967) is from approximately two kilometres north-west of the study area (Figure 2). More recently the species was recorded in 2004 in the Barwon Reserve approximately six kilometres north-west of the study area near the junction of Barwon '

10 Boulevard and Challambra Crescent, Highton (Daniel Jerabek pers. comm.). There is potentially suitable habitat for Growling Grass Frog along the Barwon River and in the large dam west of Jendes Lane (Figure 3), and the Barwon River corridor is currently considered to be of at least regional conservation significance (Appendix 1) (Ecology Partners 2009). +

11 4 POTENTIAL IMPACTS Based on the current plan for the proposed NEIP there are unlikely to be any direct impacts to Growling Grass Frog habitat along the Barwon River or its floodplain. The potential habitat within the actual NEIP, the large farm dam in the north, is proposed to be retained and its habitat enhanced. Further, the larger and to be created drainage features may also provide Growling Grass Frog habitat. However, if during construction, Growling Grass Frogs are encountered within the NEIP and/or the areas of development are expanded to include the floodplain, it is possible that potential habitats may be impacted by development. A summary of general potential impacts associated with the any development of part of the study area is outlined below. Currently new road construction, which can be a barrier to dispersal, which can remove habitat, and cause frog deaths, is not considered to be a significant issue with the construction of the NEIP for the Growling Grass Frog. However, this may change once the proposed east-west link road is designed, and the most important design feature for this is the incorporation of underpasses that are strategically positioned in areas where frogs can move between habitats. 4.1 Hydrology and Water Quality Construction activities associated with development have the potential to result in sedimentation of nearby waterways and produce sediment-laden runoff into drainage lines and the Barwon River. Sediment-laden water also has the potential to be transported offsite, downstream to additional areas containing potential habitat for the Growling Grass Frog. There is also the potential for accidental spillage of chemicals from the construction area to runoff into wetlands and drainage lines. Increase in sediment input and input of toxic substances into Victorian rivers and streams due to human activities are both listed as threatening processes under Schedule 3 of the Flora and Fauna Guarantee Act 1988 (FFG Act). Once development is complete, stormwater runoff from roads and paved surfaces has the potential to drain into drainage lines and Barwon River. After the study area is developed the volume and velocity of run-off into either the Barwon River or stormwater treatment wetlands is expected to be greater than existing run-off due to the increase in impervious area. Run-off from developed areas often contains pollutants such as fertilisers, herbicides, litter and seeds of weed species. Therefore, a reduction in water quality and weed invasion may occur in drainage lines, Barwon River, and downstream as a result of any development. Further, altered drainage patterns resulting from the development have the potential to modify the length of time current low-lying areas hold water. Overland flow should be intercepted and redirected away from the low-lying areas to prevent any adverse impacts upon water quality and native vegetation. As one of the preferred habitat variables of the Growling Grass Frog is permanent water (Heard et al. 2004a), any reduction in permanent water, such as a reduction in water levels at the large dam, may render these sites unsuitable as potential habitat or potential movement corridors. ++

12 4.2 Human Access Increased human occupancy within the study area has the potential to result in disturbance by persons entering the Barwon River and floodplain, and other retained habitat areas. This may lead to the degradation of habitat within these sites due to rubbish dumping, mechanical disturbance of vegetation from trampling, and weed invasion. However, the majority of the study area is currently experiencing disturbances associated with agricultural activities. 4.3 Weeds Increased weed encroachment into areas of terrestrial and aquatic indigenous vegetation in the study area may occur due to run-off from the development. Weeds may also be transported via construction equipment and machinery, and people/animals entering the site. Invasion of native vegetation by environmental weeds is a threatening process under Schedule 3 of the FFG Act. Excessive weed growth can smother wetland and terrestrial habitats used by frogs, rendering them unsuitable as breeding and/or foraging sites. 4.4 Dog and Cat Ownership Unrestrained dogs and cats have the potential to roam into potential frog habitats that exist within the study area. Cats in particular are known to predate upon dispersing or sheltering frogs. Predation of native wildlife by the Cat is a threatening process under Schedule 3 of the FFG Act. 4.5 Exotic Predators Plague Minnow The introduced Plague Minnow Gambusia holbrooki has been identified as a possible factor in the decline of the species (Mahony 1993; White and Pyke 1996; Hamer et al. 2002), because it eats the eggs and tadpoles of these species (Morgan and Buttermer 1996). Predation by Plague Minnow on tadpoles of the Growling Grass Frog has been identified as a significant threat to the species (Department of Environment and Conservation 2005). This species may reduce the potential of a site to support breeding populations, although the extent of predation depends on aquatic vegetation and habitat complexity, and waterbody permanency (Hamer et al. 2002). Plague Minnow is also known to occur in Barwon River and other drainage lines and farm dams within the area. The presence of this fish in water bodies, together with the lack of established emergent vegetation, reduces the habitat potential of waterbodies within the study area for the Growling Grass Frog. Red Fox The Red Fox Vulpes vulpes has been recorded on the subject site. The Red Fox is known to eat adult members of the bell frog species complex (NSW DEC 2005), although it has not been identified as a threat to the Growling Grass Frog in the Draft Recovery Plan (NSW DEC +

13 2005). Additionally, in the NSW Threat Abatement Plan for Predation by the Red Fox (NPWS 2001b), Growling Grass Frog is considered to be a species with a low sensitivity rating, which indicates that population impacts are unlikely to result from predation by the Red Fox. Nonetheless, there is likely to be some predation on frogs in the Barwon River and floodplain area by the Red Fox. +

14 The majority of the mitigation measures mentioned below (apart from those relating to the large farm dam and any more significant drainage structures) relate to enhancing frog habitat within the Barwon River floodplain, and any actions should be in consultation and approved by the relevant authorities Habitat Protection It is important that the large farm dam and any constructed wetlands/drainage systems in the study area are protected and their habitat enhanced to ensure that potential habitat for the Growling Grass Frog is maintained into the future. Where possible, connectivity should be maintained between the dam and any constructed wetlands/drainage systems for potential population viability within and around the study area Habitat Enhancement See Section Water Quality Future industrial development in the study area has the potential to result in stormwater contamination and uncontrolled run-off into existing and created frog habitat. Increases in the area of hard surfacing may result in increased run-off, nutrient levels and sediment entering the Barwon River. It is therefore recommended that vegetation removal be minimised throughout the Barwon River floodplain and that strict erosion and sediment control plans be required for all developments in the entire study area. The establishment of revegetated open space and the enhancement of the riparian zone of the Barwon River is also recommended to protect the integrity of potential frog movement corridors in that party of the study area. Water Sensitive Urban Design should be incorporated into the design of all future developments in the study area. For additional stormwater management measures see also Section Feral and domestic animal control There are Red Foxes in the study area. Foxes are known to hunt and kill bell frogs and therefore pose a risk to any Growling Grass Frog habitats in the study area. In conjunction with the future floodplain manager, it is recommended that a Feral Animal Control Plan be implemented to reduce the population size of foxes. Further, cat and dog control should also be part of this plan. +

15 5 MITIGATION MEASURES The majority of the mitigation measures mentioned below (apart from those relating to the large farm dam and any more significant drainage structures) relate to enhancing frog habitat within the Barwon River floodplain, and any actions should be in consultation and approved by the relevant authorities Habitat Protection It is important that the large farm dam and any constructed wetlands/drainage systems in the study area are protected and their habitat enhanced to ensure that potential habitat for the Growling Grass Frog is maintained into the future. Where possible, connectivity should be maintained between the dam and any constructed wetlands/drainage systems for potential population viability within and around the study area Habitat Enhancement See Section Water Quality Future industrial development in the study area has the potential to result in stormwater contamination and uncontrolled run-off into existing and created frog habitat. Increases in the area of hard surfacing may result in increased run-off, nutrient levels and sediment entering the Barwon River. It is therefore recommended that vegetation removal be minimised throughout the Barwon River floodplain and that strict erosion and sediment control plans be required for all developments in the entire study area. The establishment of revegetated open space and the enhancement of the riparian zone of the Barwon River is also recommended to protect the integrity of potential frog movement corridors in that party of the study area. Water Sensitive Urban Design should be incorporated into the design of all future developments in the study area. For additional stormwater management measures see also Section Feral and domestic animal control There are Red Foxes in the study area. Foxes are known to hunt and kill bell frogs and therefore pose a risk to any Growling Grass Frog habitats in the study area. In conjunction with the future floodplain manager, it is recommended that a Feral Animal Control Plan be implemented to reduce the population size of foxes. Further, cat and dog control should also be part of this plan. +

16 5.2 Monitoring of Growling Grass Frog Habitats Created wetlands In consultation with the appropriate floodplain manager or agency, any created wetlands should be monitored and managed over the first two years after their establishment, during which time vegetation condition should be monitored every three months. Monitoring of water quality at any created wetlands is considered essential to ensure that wetlands offer suitable habitat. Water monitoring should occur at least every three months for the first two years after wetland construction and the requirement for water quality monitoring should be reviewed after two years. Sampling methods should be consistent with EPA guidelines for water quality. Water sampling should also be conducted at existing waterbodies, such as the large farm dam, so that comparisons can be made between created versus existing wetland water chemistry. Wetlands should be at full water level within at least six months to one year after construction and if not they should be redesigned Dense aquatic vegetation may reduce the area of open water in a wetland and reduce its suitability as breeding habitat for Growling Grass Frog. If the removal of aquatic vegetation is deemed a necessary action by a qualified wetland ecologist or zoologist, then manual removal should be undertaken Potential Movement Corridors Any enhancement works along the Barwon River should also be monitored every three months to determine the progress of vegetation rehabilitation, which would be a standard requirement as part of any revegetation contract. Water quality in the river is currently not proposed to be monitored, as it has a large catchment, but some of the more significant drainage systems should be monitored every three months, paying particular attention to turbidity, total dissolved solids, salinity, and nutrient levels, which are potential gauges of industrial impacts. Habitat features along the potential movement corridors, such as rock piles, and vegetation condition should be inspected to determine their suitability for Growling Grass Frog Population Monitoring If the Growling Grass Frog is detected within the study area, the status of the species at existing and created wetlands should be determined at least once a month over their activity period (i.e. September to March), and once during the non-breeding period during construction and for at least two years after the completion of construction. Waterbodies that the species are likely to occupy should be surveyed using diurnal and nocturnal survey techniques. Diurnal searches would also include active searching beneath rocks and debris (e.g. fallen timber, corrugated iron, fence posts) for inactive frogs during a prescribed search period. Site-specific habitat variables that should be recorded during the day include those recorded in Ecology Partners A photo (at the same location) of each survey site, at both created and existing wetlands, should be taken so that changes in habitat conditions over time can be recorded. All surveys will follow the hygiene protocols specified in the Hygiene +

17 Protocol for the Control of Disease in Frogs (NPWS 2001a) to reduce the risk of transmission of chytrid fungus between frogs and between sites. Waterbodies where any calling males are recorded should be surveyed for tadpoles using fish traps containing glow sticks that are deployed for several nights at each site. Active searching for metamorphs should be conducted during diurnal or nocturnal surveys at sites where calling and/or tadpoles are recorded. Other frog species recorded during monitoring should be noted to determine species turnover at existing and created wetlands. +,

18 6 POTENTIAL HABITAT IMPROVEMENTS There is potential to include measures that will provide additional habitat for the Growling Grass Frog within the study area, or encourage the introduction of the Growling Grass Frog to the local area. During the construction of the NEIP, the majority of habitat improvements for the Growling Grass Frog will potentially be focused within and adjacent to the Barwon River floodplain. If the large dam, drainage reserves and other connecting habitats along the Barwon River are enhanced and/or constructed, there is potential for Growling Grass Frogs to colonise habitats in the future. 6.1 Opportunities for Habitat Creation and Enhancement in the Barwon River and Floodplain Growling Grass Frog has previously been detected in the Barwon River both upstream and downstream of the study area (Figure 2). Because of the positive correlation between the occurrence of Growling Grass Frog and the proximity to permanent drainage channels and rivers, it is likely that the Barwon River is an important dispersal corridor for the species in the local area. With this in mind, the Barwon River riparian corridor and the floodplain is considered a priority area for sensitive habitat creation and enhancement (Figure 3). Given that Growling Grass Frog may use the Barwon River as a dispersal corridor, waterbodies enhanced or created adjacent to the Barwon River may be colonised by the Growling Grass Frog, provided they contain the necessary habitat components such as a large size, permanent water, patches of emergent and submerged vegetation, are fish-free and have good water quality (see Section 4.1). 6.2 Wetland Design and Habitat Enhancement Previous research on the Growling Grass Frog, and Green and Golden Bell Frog, has shown that a landscape-based approach to habitat creation and management is required (Robertson et al. 2002; Hamer et al. 2002). For example, the likelihood of the species occupying a waterbody is largely dependent on the distance to a nearby occupied site. Therefore, if appropriate, it is recommended to create habitat close to the existing movement corridor (Barwon River), to augment the current extent of habitat for the Growling Grass Frog. Key design requirements to be incorporated into wetland creation should follow the recommendations of Organ (2005a, 2005b), which outlined design features for created wetlands to mitigate the impact of the proposed Pakenham Bypass. The Constructed Wetland Systems Design Guidelines for Developers (Melbourne Water 2002) should also be referred to during all phases of wetland design and construction. A summary of the key design requirements for created wetlands and the enhancement of existing wetlands (such as the large dam in the north) for the Growling Grass Frog in the study area include: Wetlands should be located within close proximity to existing potential habitat, but should limit the removal of indigenous flora species; Wetlands should be greater than 40 x 10 metres; +(

19 There should be provision of a range of edge habitats; Wetlands should have low water turbidity, be still, have low nitrate and phosphate levels, and low salinity levels; Wetlands should be surrounded by a terrestrial buffer of no less than 20 metres width, in which there is no development, mowing, slashing or use of herbicides and pesticides, but which may be landscaped with indigenous grasses, herbaceous species and low shrubby vegetation (but no trees); Wetlands should have permanent water levels between 0.5 and 2.0 metres in depth; There should be inclusion of rock piles, rock matrixes and large woody debris around wetlands; Wetlands should be planted with a dense cover and diversity of emergent, submerged and floating vegetation (Appendix 2); Access tracks and other infrastructure should not be located near created/enhanced wetlands, and there should be no apparent barriers to dispersal; Wetlands should be kept free of predatory fish such as Plague Minnow and non-native fish such as Trout; Cattle grazing should be discouraged around existing and created wetlands, and movement corridors, particularly within the riparian zone of the Barwon River; Several smaller ephemeral wetlands should be created around the larger permanent dam that provide additional habitat that is more likely to remain fish-free, because it will dry out during extended dry periods; and, Small ponds and depressions, where suitable, should be constructed between the created wetlands, to aid in the potential dispersal of Growling Grass Frogs within the Barwon River corridor. Created/enhanced wetlands should not be used for recreational purposes and should not be stocked with fish for sporting or other purposes. The suitability of vegetation for Growling Grass Frog habitat should be determined and plantings undertaken by a qualified wetland practitioner. Any undesirable weeds or aquatic vegetation that can choke wetland systems (e.g. Typha spp.) may need to be removed (preferably) by physical removal, although frogsensitive herbicides such as Roundup Bi-active may be used where this is not possible or not feasible. Damage to aquatic vegetation immediately after planting in newly created wetlands by waterfowl may be prevented by protective netting. Wetlands should be pumped dry if predatory fish invade, although the implications of draining on tadpoles and frogs in the wetland needs to be considered prior to any drainage activities Artificial Wetlands for the Management of Stormwater The introduction of an industrial development to a semi-rural area will have stormwater management requirements. Uncontrolled run-off can lead to eutrophication of waterways, decreases in aquatic biodiversity and terrestrial weed invasion, and some urban activities have the potential to result in stormwater contamination and the subsequent deterioration of surrounding soils and water. Based on discussions with Alex Wilks (TGM), there is the +'

20 opportunity to utilise a design consisting of a series of wetlands as a means to manage some of the stormwater run-off. Where significant amounts of stormwater enter the Barwon River, erosion and sediment control mechanisms should be incorporated into a staged layout of wetland pond design. These mechanisms minimise the risk of sediment-laden run-off from the industrial areas entering into naturally-occurring habitats, and where appropriate should consist of a sediment pond, a nutrient stripping pond, and an open water pond for storage. These ponds are designed to improve stormwater quality prior to entering the Barwon River, enabling water retention and storage for use on site, providing positive visual amenity to the area, and can provide additional habitat for indigenous fauna, such as the Growling Grass Frog. As surface run-off would feed these drainage systems, effective treatment measures, such as Triple Intercepter Pits (TIP) and Gross Pollutant Traps (GPT), should be installed to maintain on-going high water quality, such that any created wetlands remain suitable for Growling Grass Frogs. Wetland species which aid in the filtration and purification of stormwater should also be utilised in these systems. As amphibians are highly susceptible to variations in water quality, it is the on-going responsibility of the floodplain manager or organistation/agency to manage and maintain the TIP and GPT s to ensure their continual efficiency at removing chemical and gross pollutants from the surface stormwater runoff.

21 CONCLUSION Provided that the construction and long-term management of the study area is in accordance with this plan, there is likely to be a net improvement in habitat quality for the Growling Grass Frog and other fauna species (e.g. waterbirds). There is also a possibility that the Growling Grass Frog may naturally colonise the study area, particularly if wetlands are constructed and managed appropriately, and connection within and between waterbodies is available. The primary objective of this plan is to provide design and management recommendations required to potentially support Growling Grass Frog habitat within the study area. While several recommendations have been provided there are opportunities to modify these if additional information becomes available during construction and/or monitoring. An important element of the effective implementation of the management plan is the ongoing commitment from land developers/owners, and relevant agencies, such as City of Greater Geelong and DSE. Similarly, there needs to be continual communication between future land developers, referral authorities and specialist consultants experienced in undertaking monitoring and management of the Growling Grass Frog and its habitats. +

22 FIGURES

23

24 NORTH GEELONG GEELONG GEELONG SOUTH Study area PRINCES Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Road Barwon BREAKWATER Kilometres Figure 1 Location of the study area, Barwon Floodplain, Keystone Business Park EP Map Num: 1416 Fig 1 Issue Date: 24/6/2009 River BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE PRINCES PRINCES PRINCES PRINCES PRINCES Barwon Heads Horseshoe Bend Road SURF COAST Road Geelong Barrabool Road Waurn Ponds Corio Geelong Bay Study Area Barwon Grovedale Reedy Lake River Lake Connewarre Anglesea Road

25

26 f f f f Reedy Lake f f f f Previous Growling Grass frog record (AVW) Study area Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Geelong-Portarlington Road BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE BELLARINE Townsend Road GEELONG SOUTH Barwon 1995 River BREAKWATER EP Map Num: 1416 Fig GGF, Issue Date: 24/6/2009 PRINCES PRINCES PRINCES PRINCES PRINCES Barwon River SURF COAST Barwon Heads Road Boundary Road Figure 2 Previous Growling Grass Frog records, Barwon Floodplain, Keystone Business Park ,000 Metres

27

28 Growling Grass Frog survey area (2009) No access Study area Wilsons Road Metres Barwon River Figure 3 Fauna survey, Barwon Floodplain, Keystone Business Park EP Map Num: 1416 Fig Fauna CMP Issue Date: 24/6/2009 Jendes Lane Brearleys Lane Sparrowvale Road Tannery Road Reserve Road Horseshoe Bend Road Barwon Heads Road Note: Study area includes eastern side of road reserve only

29 APPENDICES

30 Appendix 1 Significance Assessment Criteria used by Ecology Partners Pty Ltd to define conservation significance, vegetation condition and habitat quality is provided below. A1.1. Rare or Threatened Categories for listed Victorian taxa! CONSERVATION STATUS IN AUSTRALIA (Based on the EPBC Act 1999, Briggs and Leigh 1996*) EX - Extinct: Extinct is when there is no reasonable doubt that the last individual of the species has died. CR - Critically Endangered: A species is critically endangered when it is facing an extremely high risk of extinction in the wild in the immediate future. EN - Endangered: A species is endangered when it is not critically endangered but is facing a very high risk of extinction in the wild in the near future. VU - Vulnerable: A species is vulnerable when it is not critically endangered or endangered but is facing a high risk of extinction in the wild in the medium-term future. R* - Rare: A species is rare but overall is not currently considered critically endangered, endangered or vulnerable. K* - Poorly Known: A species is suspected, but not definitely known, to belong to any of the categories extinct, critically endangered, endangered, vulnerable or rare. CONSERVATION STATUS IN VICTORIA (Based on DSE 2005, DSE 2007, FIS) x - Presumed Extinct in Victoria: not recorded from Victoria during the past 50 years despite field searches specifically for the plant, or, alternatively, intensive field searches (since 1950) at all previously known sites have failed to record the plant. e - Endangered in Victoria: at risk of disappearing from the wild state if present land use and other causal factors continue to operate. v - Vulnerable in Victoria: not presently endangered but likely to become so soon due to continued depletion; occurring mainly on sites likely to experience changes in land-use which would threaten the survival of the plant in the wild; or, taxa whose total population is so small that the likelihood of recovery from disturbance, including localised natural events such as drought, fire or landslip, is doubtful. r - Rare in Victoria: rare but not considered otherwise threatened - there are relatively few known populations or the taxon is restricted to a relatively small area. k - Poorly Known in Victoria: poorly known and suspected, but not definitely known, to belong to one of the above categories (x, e, v or r) within Victoria. At present, accurate distribution information is inadequate.,

31 A1.2. Defining Ecological Significance "#$ NATIONAL SIGNIFICANCE Flora National conservation status is based on the EPBC Act list of taxa considered threatened in Australia (i.e. extinct, critically endangered, endangered, vulnerable). Flora listed as rare in Australia in Rare or Threatened Australian Plants (Briggs and Leigh 1996). National conservation status is based on the EPBC Act list of taxa considered threatened in Australia (i.e. extinct, critically endangered, endangered, vulnerable). Fauna Fauna listed as extinct, critically endangered, endangered, vulnerable, Rare or Lower Risk (near threatened, conservation dependent or least concern) under National Action Plans for terrestrial taxon prepared for the Department of the Environment, Water, Heritage and the Arts: threatened marsupials and monotremes (Maxwell et al. 1996), bats (Duncan et al. 1999), birds (Garnett and Crowley 2000), reptiles (Cogger et. al. 1993), and amphibians (Tyler 1997). Species that have not been included on the EBPC Act but listed as significance according to the IUCN 2006 Red List of Threatened Species (IUCN 2006). Communities Vegetation communities considered critically endangered, endangered or vulnerable under the EPBC Act and considering vegetation condition. STATE SIGNIFICANCE Threatened taxa listed under the provisions of the FFG Act. Flora Flora listed as extinct, endangered, vulnerable or rare in Victoria in the DSE Flora Information System (most recent Version). Flora listed in the State Government s Advisory List of Rare or Threatened Plants in Victoria, 2005 (DSE 2005). Flora listed as poorly known in Australia in Rare or Threatened Australian Plants (Briggs and Leigh 1996). Threatened taxon listed under Schedule 2 of the FFG Act. Fauna Fauna listed as extinct, critically endangered, endangered and vulnerable on the State Government s Advisory List of Threatened Vertebrate Fauna in Victoria 2007 (DSE 2007). Listed as Data Deficient, Lower risk Near threatened, or Insufficiently Known under National Action Plans for terrestrial species prepared for the Department of the Environment, Water, Heritage and the Arts: threatened marsupials and monotremes (Maxwell et al. 1996), bats (Duncan et al. 1999), birds (Garnett and Crowley 2000), reptiles (Cogger et al. 1993), and amphibians (Tyler 1997). Commu nities Ecological communities listed as threatened under the FFG Act. (

32 Ecological vegetation class listed as threatened (i.e. endangered, vulnerable) or rare in a Native Vegetation Plan for a particular bioregion (DSE Website) and considering vegetation condition. REGIONAL SIGNIFICANCE Flora considered rare in any regional native vegetation plan for a particular bioregion. Flora Flora considered rare by the author for a particular bioregion. Fauna with a disjunct distribution, or a small number of documented recorded or naturally rare in the Otway Plain bioregion. Fauna A particular taxon that is has an unusual ecological or biogeographical occurrence or listed as Lower Risk Near Threatened, Data Deficient or Insufficiently Known on the State Government s Advisory List of Threatened Vertebrate Fauna in Victoria 2007 (DSE 2007). Communities Ecological vegetation class listed as depleted or least concern in a Native Vegetation Plan for a particular bioregion (DSE Website) and considering vegetation condition. Ecological vegetation class considered rare by the author for a particular bioregion. LOCAL SIGNIFICANCE Local significance is defined as flora, fauna and ecological communities indigenous to a particular area, which are not considered rare or threatened on a national, state or regional level. '

33 A1.3 Defining Site Significance The following geographical areas apply to the overall level of significance with respect to the current survey. National: State: Regional: Local: Australia Victoria Otway Plain bioregion Within 10 kilometres surrounding the study area "$$ A site is of National significance if: NATIONAL SIGNIFICANCE - it regularly supports, or has a high probability of regularly supporting individuals of a taxon listed as Critically Endangered or Endangered under the EPBC Act and/or under National Action Plans for terrestrial taxon prepared for the Department of the Environment, Water, Heritage and the Arts. - it regularly supports, or has a high probability of supporting, an important population as defined under the EPBC Act of one or more nationally vulnerable flora and fauna taxon. - it is known to support, or has a high probability of supporting taxon listed as Vulnerable under National Action Plans. - it is known to regularly support a large proportion (i.e. greater than 1%) of a population of a taxon listed as Conservation Dependent under the EPBC Act and/or listed as Rare or Lower Risk (near threatened, conservation dependent or least concern) under National Action Plans. - it contains an area, or part thereof designated as critical habitat under the EPBC Act, or if the site is listed under the Register of National Estate compiled by the Australian Heritage Commission. - it is a site which forms part of, or is connected to a larger area(s) of remnant native vegetation or habitat of national conservation significance such as most National Park, and/or a Ramsar Wetland(s). A site is of State significance if: STATE SIGNIFICANCE - it occasionally (i.e. every 1 to 5 years) supports, or has suitable habitat to support taxon listed as Critically Endangered or Endangered under the EPBC Act and/or under National Action Plans. - it regularly supports, or has a high probability of regularly supporting (i.e. high habitat quality) taxon listed as Vulnerable, Near threatened, Data Deficient or Insufficiently Known in Victoria (DSE 2005, 2007), or species listed as Data Deficient or Insufficiently Known under National Action Plans. - it contains an area, or part thereof designated as critical habitat under the FFG Act. - it supports, or likely to support a high proportion of any Victorian flora and fauna taxa. - it contains high quality, intact vegetation/habitat supporting a high species richness and diversity in a particular Bioregion. - it is a site which forms part of, or connected to a larger area(s) of remnant native vegetation or habitat of state conservation significance such as most State Parks and/or Flora and Fauna Reserves.