Draft National Recovery Plan for the Australasian Bittern Botaurus poiciloptilus
The Species Profile and Threats Database pages linked to this recovery plan is obtainable from: http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl
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Cover page: Australasian Bittern (Botaurus poiciloptilus) © Richard Hall
2 CONTENTS SUMMARY ...... 4 INTRODUCTION ...... 6 2.1 Conservation status ...... 6 2.2 Taxonomy ...... 7 2.3 Species description ...... 7 2.4 Species distribution in Australia...... 7 2.5 Population trends ...... 10 2.6 Ecology ...... 10 2.7 Habitat critical to the survival of the Australasian Bittern ...... 11 THREATS ...... 13 3.1 Historical causes of decline ...... 13 3.2 Current threatening processes ...... 13 3.2.1 Reduced wetland availability due to changed water flows ...... 13 3.2.2 Habitat loss and/or alteration ...... 14 3.2.3 Climate variability and change ...... 15 3.2.4 Reduced water quality ...... 15 3.2.5 Invasive species ...... 16 3.2.6 Low genetic diversity ...... 16 3.2.7 Threat prioritisation ...... 16 POPULATIONS UNDER PARTICULAR PRESSURE ...... 18 RECOVERY PLAN VISION, OBJECTIVES AND STRATEGIES ...... 20 ACTIONS TO ACHIEVE THE SPECIFIC OBJECTIVES ...... 20 Strategy 1 – Implement management strategies to reduce threats to Australasian Bittern and their habitat ...... 21 Strategy 2 – Enhance protection, improve the quality and increase the extent of suitable habitat for the Australasian Bittern ...... 25 Strategy 3 – Improve knowledge of the biology and ecology of Australasian Bittern and implement a monitoring strategy to identify population trends ...... 27 Strategy 4 - Increase stakeholder participation in Australasian Bittern conservation and management...... 29 Strategy 5 – Coordinate, review and report on recovery process ...... 31 DURATION AND COST OF THE RECOVERY PROCESS ...... 32 EFFECTS ON OTHER NATIVE SPECIES AND BIODIVERSITY BENEFITS ...... 33 SOCIAL AND ECONOMIC CONSIDERATIONS...... 33 AFFECTED INTERESTS ...... 34 CONSULTATION ...... 35 ORGANISATIONS/PERSONS INVOLVED IN EVALUATING THE PERFORMANCE OF THE PLAN . 36 REFERENCES ...... 37
3
SUMMARY Australasian Bittern (Botaurus poiciloptilus)
Family: Ardeidae Current status of taxon: Environment Protection and Biodiversity Conservation Act 1999 (Cwlth): Endangered Biodiversity Conservation Act 2016 (New South Wales): Endangered Nature Conservation Act 2014 (Australian Capital Territory): Endangered Flora and Fauna Guarantee Act 1988 (Victoria): Threatened National Parks and Wildlife Act 1972 (South Australia): Vulnerable Biodiversity Conservation Act 2016 (Western Australia): Endangered
IUCN Red List of Threatened Species: Endangered
Distribution and habitat: In addition to Australia, the Australasian Bittern occurs in New Zealand and New Caledonia. In Australia, Australasian Bitterns can be divided into two subpopulations, the south eastern and south western subpopulations. The species occurs discontinuously along the east coast from south east Queensland to south east South Australia and Tasmania, extending into the Murray-Darling Basin. In Western Australia, it is presently confined to widely separated parts of the south-western and south-eastern coast and a small number of wetlands farther inland. Breeding of both subpopulations occurs at both coastal and inland sites, at a much smaller subset of wetland sites. The Australasian Bittern preferred habitat comprises wetlands with dense vegetation from 0.5 – 3.5 metres in height, where it forages in still, shallow water up to 0.3 m deep, often at the edges of pools or waterways, or from platforms or mats of vegetation over deep water. It favours permanent and seasonal freshwater habitats, particularly those dominated by sedges, rushes and reeds, as well as rice crops.
Recovery Plan Vision, Objective, and Strategies:
Long-term Vision
The Australasian Bittern population has increased in size to such an extent that the species no longer qualifies for listing as threatened under any of the Environment Protection and Biodiversity Conservation Act 1999 listing criteria.
Recovery plan objective: The objective of this recovery plan is to demonstrate, by 2030, an increasing trend in the number of mature individuals being recorded in annual surveys at key locations compared to 2020 baseline counts, and habitat critical to the survival is being managed to meet the ecological requirements of the Australasian Bittern.
Strategies to achieve objectives 1. Implement management strategies to reduce threats to Australasian Bittern and their habitat
4 2. Enhance protection, improve the quality and increase the extent of suitable habitat for the Australasian Bittern
3. Improve knowledge of the biology and ecology of Australasian Bittern and implement a monitoring strategy to identify population trends
4. Increase stakeholder participation in Australasian Bittern conservation and management
5. Coordinate, review and report on recovery process
Criteria for success: This recovery plan will be deemed successful if, within 10 years, all of the following have been achieved: • The abundance of Australasian Bittern has increased from 2020 baseline counts
• The number of sites supporting Australasian Bittern has increased from 2020 baseline counts, and the quality of the sites has improved, as measured against a range of environmental health indicators
• Understanding of the species’ ecology has increased, in particular knowledge of movement patterns and habitat use
• There is increased participation by key stakeholders and the public in recovery efforts and monitoring
Recovery team: Recovery teams provide advice and assist in coordinating actions described in recovery plans. They include representatives from organisations with a direct interest in the recovery of the species, including those involved in funding and those participating in actions that support the recovery of the species. The Australasian Bittern Recovery Team has the responsibility of providing advice, coordinating and directing the implementation of the recovery actions outlined in this recovery plan. The membership of the Recovery Team includes individuals with relevant government agencies, non-government organisations and expertise from independent researchers and community groups.
5 INTRODUCTION This document constitutes the ‘National Recovery Plan for Australasian Bittern’. The plan considers the conservation requirements of the species across the part of its range lying within Australia and identifies the actions to be taken to ensure the species’ long-term viability in nature, and the parties that will undertake those actions.
Principal threats to the Australasian Bittern include the loss and degradation of wetland habitats through altered water regimes, drainage and diversion, impacts on coastal wetlands for urban development and farming. Other potential threats to the species may include reduced water quality, predation by introduced foxes (Vulpes vulpes) and cats (Felis catus), overgrazing by livestock, and detrimental fire regimes.
Accompanying Species Profile and Threats Database (SPRAT) pages provide background information on the biology, population status and threats to the ‘species’. SPRAT pages are available from: http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl.
2.1 Conservation status
The Australasian Bittern is a listed threatened species under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The species is also listed under State Legislation (Table 1).
The species was included in the Endangered category of the EPBC Act in 2011 as the estimated total number of mature individuals of the species is low and evidence suggests that the number will continue to decline at a high rate. The species is also suspected to have undergone a severe reduction in population numbers as a result of the reduction in the species’ area of occupancy and the loss of habitat and breeding grounds (TSSC 2011).
Table 1: National and state conservation status of the Australasian Bittern.
Legislation Conservation Status
Environment Protection and Biodiversity Conservation Act 1999 (EPBC Endangered Act)
Nature Conservation (Wildlife) Regulation 2006 Endangered
Biodiversity Conservation Act 2016 (New South Wales) Endangered
Nature Conservation Act 2014 (Australian Capital Territory) Endangered
National Parks and Wildlife Act 1972 (South Australia) Vulnerable
Flora and Fauna Guarantee Act 1988 (Victoria) Threatened
Biodiversity Conservation Act 2016 (Western Australia) Endangered
6 2.2 Taxonomy
Conventionally accepted as Botaurus poiciloptilus (Wagler, 1827). No subspecies have been described. The species is commonly known as the Australasian Bittern. It is also known as the Boomer, Bullhead, Bunyip, Black-backed or Brown Bittern.
2.3 Species description
Australasian Bitterns are large, stocky, thick–necked, heron–like birds. The species grows to a length of 66– 76 cm and has a wingspan of 1,050–1,180 mm. The average male weighs approximately 1,400 g and the average female weighs approximately 900 g (Marchant and Higgins 1990). The upper-parts of the body are brown and dark brown to black, mottled and buff, in complex patterns that aid the bird’s concealment in swamp vegetation. The under-parts of the body are streaked and scalloped, brown and buff. The species has a prominent black–brown stripe running down the side of the neck, the eyebrow is pale, and the chin and upper throat are white. The bill is straight, pointed and straw yellow to buff in colour with a dark grey ridge. The legs and feet are pale green to olive and the eyes are orange–brown or yellow (Marchant and Higgins 1990; Pizzey and Knight 1997). Darker and paler variants of the plumage have been observed in adults. Juveniles are generally paler than adults and have heavier buff flecking on the back (Marchant and Higgins 1990; Pizzey and Knight 1997).
Australasian Bitterns occur mainly in freshwater wetlands in the temperate southeast and southwest of Australia and, exceptionally, in estuaries or tidal wetlands (Marchant and Higgins 1990). Australasian Bitterns’ preferred habitat comprises wetlands with dense vegetation, especially where there is a mosaic of cover, from 0.5 – 3.5 metres in height, where they forage in still, shallow water up to 0.3 m deep, often at the edges of pools or waterways, or from platforms or mats of vegetation over deep water. They favour permanent and seasonal freshwater habitats, particularly those dominated by sedges, rushes and/or reeds (e.g. Phragmites, Cyperus, Eleocharis, Juncus, Typha, Baumea, Bolboschoenus) or cutting grass (Gahnia) growing over a muddy or peaty substrate, as well as rice crops (Marchant and Higgins 1990). In south-western Australia the species also occurs in wetlands where thickets of wetland shrubs (e.g. Melaleuca, Agonis spp.) provide patches of tall cover within sedge-dominated habitat. In the Murray-Darling Basin, Australasian Bitterns occur in floodplain swamps that may include lignum (Duma florulenta) shrubs within sedge or reed beds as well as in commercial rice-fields (NSW Riverina). Despite occurring in a range of wetland types, breeding is known to occur in a much smaller sub-set of locations.
2.4 Species distribution in Australia
In Australia, the Australasian Bittern occurs from south-east Queensland to south-east South Australia as far as the Adelaide Region, southern Eyre Peninsula, Tasmania and in the southwest of Western Australia (Jaensch et al. 1988; Marchant and Higgins 1990; Garnett et al. 2011). Vagrants have also been recorded from northern Australia, including one record from Argyle Downs in the extreme north east of Western Australia (Marchant and Higgins 1990). Due to geographical isolation over 1500 km of mainland without suitable habitat, the population can be divided into two subpopulations, the south-eastern and south-western subpopulations. The Australasian Bittern also occurs in New Zealand and New Caledonia (Marchant and Higgins 1990).
In Queensland, the species occurs as far north as Yeppoon and west to Wyandra. In the south-east there is habitat remaining on Fraser Island, the Fraser Coast, North Stradbroke Island, Redlands and out into the Lockyer Valley. Key areas in Queensland where the species has been reliably seen in the past include the flood plains south of Byfield State Forest, Garnett's Lagoon, Bribie Island and Lake Clarendon.
7 In New South Wales, it occurs along the coast and is also frequently recorded in the Murray-Darling Basin, notably in floodplain wetlands of the Murray, Murrumbidgee, Lachlan, Macquarie and Gwydir Rivers.
In Victoria, it is recorded mostly in the southern coastal areas and in the Murray River region of central northern Victoria.
In Tasmania, the species was formerly more widespread, however it is now absent from some major wetlands that have dried out (Marchant and Higgins 1990; Garnett and Crowley 2000). It occurs most commonly in the coastal regions in the north east, the east coast and on the islands of Bass Strait. It also commonly occurs in the upper Derwent River estuary and Lakes Crescent and Sorell in central Tasmania (R. Gaffney pers. comm. 2018).
In South Australia, it primarily occurs in the south-east, ranging north to the Murray River corridor and the Adelaide region, and west to the southern Eyre Peninsula and Kangaroo Island.
8
9 In Western Australia, the Australasian Bittern was formerly widespread in the south-west, ranging north to Moora, east to near Cape Arid, and inland possibly as far as the Toolibin Lake area (Jaensch et al. 1988). However, following extensive loss of habitat throughout the 1900s (e.g. due to drainage and salinization) and ongoing urban development, it is now likely that it only occurs rarely on the western coastal plain between Lancelin and Busselton, in the core area of occurrence in the southern coastal region from Augusta to the east of Albany and inland to some wetlands in the Jarrah forest belt (Lake Muir district), with small, isolated populations in swamps near Esperance eastwards to near Cape Arid (Jaensch et al. 1988).
2.5 Population trends
The estimated number of mature individuals is 3,500 (Herring et al. 2019). The Action Plan for Australian Birds 2010 (Garnett et al. 2011) suggested there were less than 1,000 mature Australasian Bitterns within the Australian population, and that the population was likely still decreasing. Based on two years of surveys at all wetlands where Australasian Bitterns had been reported between 1998 and 2008, BirdLife Australia estimated the number of adult birds in 2009-2010 to be 3-16 in Queensland, 82-162 in New South Wales, 86-248 in Victoria, 12-100 in Tasmania, 26-116 in South Australia and 38-154 in Western Australia – a national total of 247-796 (Birds Australia 2010; Garnett et al. 2011).
Based on the published data, decreases in this species have been occurring for a number of decades. The reporting rate in national Atlas surveys has decreased from being recorded in 260 10-minute grid squares in 1977-1981, to 142 squares in 1998-2003, and 61 in 2003-2008 (Birds Australia 2010; Garnett et al. 2011). The reporting rate declined by >90 per cent in Tasmania and Western Australia, and by 63 per cent in the Riverina. The long-term rate of decline is estimated to be 20 – 30 per cent over two generations (11 years).
The area of occupancy of the Australasian Bittern in Australia is thought to have declined by 70 per cent between 1977 and 2008. These declines are considered to have led to a comparable decline in the size of the adult population.
Occupancy modelling from 2013-2017 in the Riverina region of New South Wales produced estimates of 368- 409 for “early permanent water” rice crops in the Murrumbidgee and Coleambally Irrigation Areas (Herring et al. 2019). Conservative estimates for “delayed permanent water” crops and for the unsurveyed Murray Irrigation Area suggest the Riverina’s rice fields support 500-1000 mature Australasian Bitterns in most years, representing about 59 per cent of the national population (Herring et al. 2019). Reduced water allocations associated with drought, the trend towards cotton and other alternative irrigation water uses that do not support bitterns, and a shift away from “early permanent water” rice crops, which are favoured by bitterns, suggests a decline in the rice field population is likely (Herring et al. 2019).
Population estimates are largely based on skewed citizen science records and there is a degree of uncertainty of population trends across the range of the Australasian Bittern. Further complicating the matter is the level of mis-identification inherent in Australasian Bittern records. Immature Nankeen Night Herons (Nycticorax caledonicus) and Australian Little Bittern (Ixobrychus dubius) can be mistaken for Australasian Bittern by inexperienced observers.
2.6 Ecology
The knowledge base on Australasian Bittern is relatively weak and based on a small number of localised studies or observations, consistent with the secretive nature of the species and difficulty for researchers in accessing its preferred dense, swampy habitats. Concerted programs of observation by BirdLife Australia and some government agencies in the past two decades have improved knowledge of occurrence and numbers (Herring et al. 2016, 2019)
10 The Australasian Bittern occurs solitarily, in pairs or dispersed aggregations of up to 34 birds (M. Herring, pers. comm. 2019). It is likely to be sedentary in permanent habitats, but regular post-breeding dispersal of 400-600 km from inland rice fields to coastal wetlands has been recorded in south-eastern Australia (Bitterns in Rice Project, 2019; Herring et al. 2016).
The Australasian Bittern breeds from October to February in single solitary pairs, or polygamously with up to three nesting females per booming male (Bitterns in Rice Project 2016). The species nests in densely vegetated freshwater wetlands, building its nests within dense cover over shallow water placed about 30 cm above the water level (Marchant and Higgins 1990). In rushland, it may avoid breeding in the densest areas (Marchant and Higgins 1990), and in reedbeds may prefer smaller patches, rather than continuous stands (M. Herring, pers. comm. 2019). If population densities are high, it may resort to more open wetlands for nesting, such as in stunted Acacia swamps (Marchant and Higgins 1990). Clutch size is usually four or five, but ranges from three to six (Serventy and Whittell 1976; Marchant and Higgins 1990).
The Australasian Bittern appears to be capable of moving between habitats as suitability changes. It can occur in high densities in temporary or infrequently filled wetlands during exceptionally wet years, and will also use ephemeral wetlands when moving from areas that are drying out (Garnett et al. 2011). Monitoring data provides evidence of seasonal movements and also that they respond to favourable conditions at key wetlands. Analysis of data collected at regularly monitored wetlands in the Melbourne area (monthly surveys) shows an influx of birds during the non-breeding season between April and October, with a peak numbers in August (Kingsford et al. 2014). In 2012, satellite tracking demonstrated that birds move between the Murray Darling Basin and coastal South Australia, Victoria and New South Wales, so the winter influx around Melbourne is likely to be of birds which breed in the Riverina region. The mobility of Australasian Bitterns makes the species hard to census as there is a risk of double counting birds recorded at different wetlands. Recent work in New Zealand has revealed their population to also be highly mobile and recent population estimates may be too high due to the likelihood of individual birds being counted multiple times.
In areas influenced by water regulation which has reduced the variation of water flow into wetlands, some species such as the Australasian Bittern have increased in numbers in some areas due to newly created areas of suitable habitat. However, overall this has not had a significant effect on the total population size of the species.
Based on occupancy modelling of the rice fields in southern New South Wales, and in the absence of similar work in other locations, rice fields are now known to support about 40 per cent of the total population (Herring et al. 2019). These agricultural wetlands are typically flooded from October-April, with Australasian Bitterns commencing nesting in December and January when there is sufficient cover and prey. Rice height is a maximum of around 1.1 m, with water depths usually 15-25 cm. The most important prey for Australasian Bitterns in rice fields is tadpoles, frogs, fish and dragonfly larvae. In “early permanent water” crops, ponding is consistent from October-April, and potential fledging of all chicks prior to harvest is the norm, however a contraction of the ponding period – “delayed permanent water” – shorter season varieties and mid-season drainage are agronomic trends likely to reduce opportunities for successful breeding. Rice fields are a seasonal attraction and Australasian Bitterns make widespread use of the surrounding irrigation infrastructure, such as vegetated channels and recycle dams, particularly between rice growing seasons (M. Herring, pers. comm. 2019).
There is very little data available but age of maturity of the Australasian Bittern is estimated to be one year and the life expectancy is estimated to be 11 years. These figures are based on figures for Botaurus stellaris (Eurasian Bittern). The generation length for the species is estimated to be 5.5 years (BirdLife International 2019).
2.7 Habitat critical to the survival of the Australasian Bittern
11 As noted above, the habitat, or biophysical environment, of the Australasian Bittern varies across its range, so it is not possible to generate one detailed description or definition of habitat critical to survival. The habitat critical to the survival of the Australasian Bittern may be more usefully defined at a bioregional scale that takes into account the combination of plants, animals, water depth, geology, landforms, and climate that is relevant to a geographical unit.
In general, Australasian Bitterns occur mainly in freshwater wetlands in the temperate southeast and southwest of Australia and, exceptionally, in estuaries or tidal wetlands (Marchant and Higgins 1990; Figure 1). Australasian Bitterns’ preferred habitat comprises wetlands with dense vegetation, especially where there is a mosaic of cover, from 0.5 – 3.5 metres in height, where they forage in still, shallow water up to 0.3 m deep, often at the edges of pools or waterways, or from platforms or mats of vegetation over deep water. They favour permanent and seasonal freshwater habitats, particularly those dominated by sedges, rushes and/or reeds (e.g. Phragmites, Cyperus, Eleocharis, Juncus, Typha, Baumea, Bolboschoenus) or cutting grass (Gahnia) growing over a muddy or peaty substrate (Marchant and Higgins 1990). In south-western Australia the species also occurs in wetlands where thickets of wetland shrubs (e.g. Melaleuca, Agonis spp.) provide patches of tall cover within sedge-dominated habitat. In the Murray-Darling Basin, Australasian Bitterns occur in floodplain swamps that may include lignum (Duma florulenta) shrubs within sedge or reed beds as well as in commercial rice-fields (NSW Riverina). Despite occurring in a range of wetland types, breeding is only known to occur at a smaller number of locations.
As a guide, habitat critical to the survival of the Australasian Bittern can be considered to include:
• Any wetland habitat where the species is known or likely to occur (breeding or foraging habitat) within the indicative distribution map (Figure 1); and
• Any location with suitable habitat outside the above area that may be periodically occupied by Australasian Bittern.
Habitat critical to the survival of the Australasian Bittern occurs across a wide range of land tenures, including on Indigenous Protected Areas, freehold land, state reserves, and national parks. It is essential that the locations where the species regularly occurs is given the highest protection and conservation measures target these productive habitats. Sympathetic management of buffer areas adjoining nesting and foraging habitats is also important to consider. Buffer zones will depend on the nature and location of the activity (e.g. adjacent to the wetland vs activity in the catchment) and can be informed by expert opinion.
When considering developments in any part of the Australasian Bittern’s range, including in areas where the species ‘may occur’, surveys for occupancy at the appropriate times of the year remain an important tool in establishing the areas importance for the Australasian Bittern. In addition, consistent with natural fluctuations in availability of wetland habitat in Australia (whether an entire wetland or a temporarily inundated zone of a wetland), it is also important to note that the Australasian Bittern opportunistically use areas depending on the occurrence of suitable habitat and prey species. So areas that may be important habitat over time might not have birds in any given year. This pattern of habitat use means that recent survey data and historical records and presence of suitable habitat need to be considered when assessing the relative importance of a site or region for the Australasian Bittern.
12 THREATS
3.1 Historical causes of decline
It is thought that the Australasian Bittern has been in decline for at least the past 30 years and declines since 2000 have been more pronounced (Garnett et al. 2011). The decline has been detected across both the eastern and western subpopulations and is associated with the loss of key breeding habitats (Garnett et al. 2011; DBCA 2018; Herring et al. 2019).
3.2 Current threatening processes
The main identified threats to the Australasian Bittern are the reduction in extent and quality of habitat due to the diversion of water away from wetlands (primarily for irrigation as well as groundwater extraction), the drainage of swamps, climate variability and change, the loss or alteration of wetland habitats due to urban and agricultural development, peat mining, predation by introduced animals such as foxes (Vulpes vulpes) and cats (Felis catus), reduced water quality as a result of increasing salinity, siltation and pollution, and overgrazing by livestock and detrimental fire regimes (Jaensch and Vervest 1988; Marchant and Higgins 1990; Kingsford and Thomas 1995; Garnett and Crowley 2000; Kingsford 2000; Jaensch 2004; Pickering 2013; DBCA 2018; Herring et al. 2019).
3.2.1 Reduced wetland availability due to changed water flows
The major threat to the Australasian Bittern in Australia is the reduction in extent and quality of habitat, due to the diversion of water away from wetlands (primarily for irrigation as well as groundwater extraction), peat mining and the drainage of swamps (Marchant and Higgins 1990; Kingsford and Thomas 1995; Garnett and Crowley 2000; Kingsford 2000; Jaensch 2004; Garnett et al. 2011; DBCA 2018). Over the past 100 years, many suitable wetland sites in both eastern and south western Australia have been lost because of the alteration of habitat (Kingsford 2000; Garnett et al. 2011). Across the range of the species, proposals to expand or create new irrigation schemes (dams) need to be mindful of the potential impacts to Australasian Bittern and its habitats, particularly during extended drought conditions.
In the Murray-Darling Basin, reduction in floodplain inundation due to water harvesting and alteration of drainage systems has adversely affected much of the Australasian Bittern’s seasonal habitat (Jaensch 2004). Many of the Murray–Darling Basins wetlands are no longer inundated or are rarely available for use by the species due to river regulation and water harvesting for irrigation (Jaensch, pers. comm., 2005). For example, there has been a 70 per cent reduction in large water flows to the Gwydir Wetlands, NSW. As a consequence, the Gwydir Wetlands now only floods five per cent of the time compared to a previous 17 per cent of the time (Kingsford 2000). In addition, the Macquarie Marshes have reduced in size by 40–50 per cent as a result of a 21 per cent decline in the flow of water to the wetland (Kingsford 2000).
Flow regulation is impacting many rivers in the Murray-Darling Basin, with approximately 4,000 dams, weirs and other barriers (Lintermans 2007) facilitating water collection in impoundments, diversion through irrigation channels and direct pumping from rivers, largely for agricultural use. Across the Basin water regulation has significantly altered natural flow regimes, particularly in regard to seasonal and inter-annual flows and floodplain inundation (Kingsford et al. 2015). It has also altered both the quality and availability of floodplain habitats, such as backwaters and billabongs, due to reduced flooding. The Murray-Darling Basin Authority has recently focussed environmental water priorities on floodplain inundation to provide lateral connectivity (MDBA 2015). Environmental watering events in the Barmah-Millewa and Lowbidgee wetlands have supported significant numbers of Australasian Bitterns, with confirmed breeding (Belcher et al. 2016, Herring et al. 2019b). Watering events in the Kerang Lakes region, Lachlan, Macquarie and Gwydir catchments have most likely achieved similar breeding events that benefit the species in the Murray-Darling Basin.
13 Increased extraction of groundwater due to escalating demand for water in urban areas and declining rainfall is another factor in wetland availability, especially on the Swan Coastal Plain, Western Australia (DBCA 2018). Groundwater dependent wetlands in this sandplain can be dry for longer periods. In contrast, as both an immediate and continued gradual consequence of clearing of woodland for agriculture in the wheatbelt of south-western Australia, runoff to many wetland basins has increased, drowning the otherwise seasonally inundated wooded and sedgeland—some of which probably was used intermittently by Australasian Bittern— leaving bare basins with only dead trees remaining (DBCA 2018).
3.2.2 Habitat loss and/or alteration
Loss of wetlands
Over the past 150 years, many wetlands suitable for Australasian Bittern in both eastern and south western Australia have been destroyed, especially due to drainage (Kingsford 2000; Garnett et al. 2011). While occurring throughout the range of occurrence of the Australasian Bittern, this impact would have been especially severe in the formerly extensive swampy landscape of the south-east of South Australia (drained mainly from 1949-1972) and in and near each of the major cities of southern Australia.
Ongoing loss of swampy wetlands suitable for or known to have supported Australasian Bittern, with replacement by urban development and infrastructure, has continued in more recent decades notably in the rapid expansion of the suburbs of Perth, Melbourne and the Gold and Sunshine Coasts, Queensland.
As well as outright loss, wetlands with Australasian Bittern habitat have been cleared of the vegetation necessary for the species to occur and this is an ongoing phenomenon. This applies to urban regions of coastal Australia but also inland. In NSW, much of the Gwydir Wetlands has been cleared and converted from grazing to cropped agriculture, leaving only very small areas of habitat suitable for bitterns (R. Jaensch, pers. comm., 2005). One of the drivers for this trend has been spread of Lippia (Phyla canescens), a mat-forming weed that thrives under conditions of reduced inundation, reducing suitable natural fodder for livestock and forcing landholders to control it by ploughing and cropping. An additional risk for natural wetlands is geomorphic change – natural erosion and sedimentation processes that can isolate wetlands (i.e. Macquarie Marshes, New South Wales). This is primarily a land and water management issue that is exacerbated by river regulation, catchment land use (erosion) and water quality (turbidity).
Because of its comparatively specialised habitat requirements (i.e. densely vegetated wetlands), the species is much more sensitive to habitat loss than many other wetland birds (Garnett and Crowley 2000). Although many sites occupied by Australasian Bitterns are now protected, the species continues to be threatened by ongoing wetland loss and changes to vegetation cover. The encroachment by River Red Gum (Eucalyptus camaldulensis) and subsequent loss of the open Moira Grass Plains from areas like the Barmah-Millewa wetlands has the potential to reduce foraging opportunities for Australasian Bitterns. The coastal zone in Australia is still subject to intense and escalating pressure from housing, semi–rural and other developments and the swampy vegetation in some wetlands has declined as wetlands become deeper sumps for increased stormwater from paved and other hard surfaces in expanding urban areas (Jaensch 2004).
Fire
Intense and frequent bushfires or prescribed burning in wetlands reduces the density and cover of vegetation that forms the core habitat of the Australasian Bittern. Wetlands in southwest Australia have lost vegetation habitat due to summer fires when wetlands are dry (DBCA 2018). Many wetlands that support Australasian Bittern have deep peat beds. Severe fires can burn these peat beds and convert wetlands from shallow wetlands suitable for Australasian Bittern to deep wetlands with only minimal fringing vegetation which do not support Australasian Bittern. The combination of a period of dry phases followed by fire resulted in the loss of an estimated 60-70 per cent of the reed beds in the Macquarie Marshes, New South Wales (Oct-Nov 2019). While the Marshes would not have been providing habitat for Australasian Bitterns at the time, given that the
14 wetlands were dry, this fire event is likely to have detrimental effect on the rigour and extent of the reed beds in this system.
Individual wetlands may require different fire regimes depending on vegetation type and location. In Western Australia, without occasional fire, rush or sedge dominated wetlands may become too dense for the movement of Australasian Bittern (A. Clarke, pers. comm. cited in DBCA 2018).
Livestock overgrazing
Livestock overgrazing can, through grazing and trampling, directly damage nests, reduce foraging habitat and reduce cover from predators. The Australasian Bittern is sensitive to habitat damage as it has relatively specialised habitat requirements, preferring wetlands with dense vegetation.
3.2.3 Climate variability and change
In Western Australia the majority of the range of the Australasian Bittern is within an area which is undergoing reduced rainfalls over the past few decades. The impact of climate change on Australasian Bittern in WA was assessed as a major threat to the species (Pickering 2013, DBCA 2018). This drying climate reduces the peak water level and peak area of wetting in wetlands during the entire year which is affecting the quality and quantity of breeding wetlands and drought refuges. In seasonal wetlands the time period that wetlands are dry is increasing and thus increasing the threat of fire destroying wetland vegetation.
3.2.4 Reduced water quality
Reduced water quality due to increased salinity, acidification, siltation and pollution is having an ongoing impact on the species’ habitat. In the wheatbealt of inland south western Australia, historical clearing of extensive natural woodlands for crops and sheep raising has led to rising water tables (not supressed by the trees), which have brought salt to the land surface, wetlands and waterways. This salinisation impacted hundreds of inland and south-eastern coastal swamps and has excluded the Australasian Bittern from former inland locations (Jaensch 2004). For example, Yarnup Swamp in the Muir–Unicup wetlands is no longer used by the Australasian Bittern due to increased salinity levels since the mid-1980s. Since Cobertup East Swamp in the Muir-Unicup wetlands became acidified in 2005, Australasian Bittern has no longer been recorded at this swamp (Pickering 2013).
Siltation in waterways occurs due to reduced vegetation cover in catchments resulting from human landuse. At the mouth of the Snowy River, Victoria, siltation has caused the back flow of saline water which has destroyed the species’ reed-bed habitat in Lake Corringle in Victoria. Consequently, the Australasian Bittern is no longer found at this location (Birds Australia 2009).
In the Murray-Darling Basin salinity is a major problem causing extensive degradation in some areas (Kingsford 2000). Elevated salinity levels could also negatively affect Australasian Bittern prey sources, such as invertebrates.
Regulated river flows have the potential to reduce water quality by excessively raising or lowering water temperatures, reducing dissolved oxygen levels and increasing nutrient and contaminant loads (Kingsford 2000). These changes can result from altered flows caused by water diversion, impoundment or sustained dry periods reducing run-off. Water quality can also be impacted by urban and agricultural run-off, which can lead to phytoplankton blooms, reduced oxygen levels and increased salinity.
Pollution in wetlands is likely to cause a decline in many of the prey species of the Australasian Bittern, such as eels, freshwater crayfish and frogs which in turn may have a negative effect on bittern populations and their health (Marchant and Higgins 1990).
15
3.2.5 Invasive species
Invasive herbivores
Invasive herbivores such as pigs, horses, goats and deer degrade wetlands important for Australian Bittern by digging up wetlands edges and removing vegetation cover. Hard hooved species trample wetland vegetation and have to potential to damage nests (DBCA 2018).
Predation
The Australasian Bittern is subject to the predation of eggs and juveniles by foxes (Vulpes vulpes) and cats (Felis catus), rats and pigs (Garnett and Crowley 2000; DBCA 2018). Foxes are known to predate on ground- nesting birds across the range of the Australasian Bittern (NSW National Parks and Wildlife Service 2001), and the impact of foxes on young chicks of the similar species, the Eurasian Bittern, has been well documented (Taylor et al. 2006).
3.2.6 Low genetic diversity
The estimated number of mature individuals is 3,500. A small population is more susceptible to demographic and genetic stochastic events, which can impact the long term survival of the population. Research is required to understand the genetic structure of Australasian Bittern and may be used to identify important populations and appropriate management units.
3.2.7 Threat prioritisation
Each of the threats outlined above has been assessed to determine the risk posed to the Australasian Bittern population using a risk matrix. This in turn determines the priority for actions outlined below. The threats were considered in the context of the current management regimes. The impact of that threat has been assessed assuming that existing management measures continue to be applied appropriately. If management regimes change then the level of risk associated with threats may also change. The risk matrix considers the likelihood of an incident occurring and the consequences of that incident. Threats may act differently in different parts of the species range and at different times of year, but the precautionary principle dictates that the threat category is determined by the population at highest risk. Population-wide threats are generally considered to present a higher risk.
The risk matrix uses a qualitative assessment drawing on peer reviewed literature and expert opinion. In some cases the consequences of activities are unknown. In these cases, the precautionary principle has been applied. Levels of risk and the associated priority for action are defined as follows:
Very High - immediate mitigation action required
High - mitigation action and an adaptive management plan required, the precautionary principle should be applied
Moderate – obtain additional information and develop mitigation action if required
Low – monitor the threat occurrence and reassess threat level if likelihood or consequences change
16
Table 2. Risk Prioritisation
Likelihood of Consequences occurrence
Not Minor Moderate Major Catastrophic significant
Almost certain Low Moderate Very High Very High Very High
Likely Low Moderate High Very High Very High
Possible Low Moderate High Very High Very High
Unlikely Low Low Moderate High Very High
Rare or Low Low Moderate High Very High Unknown
Categories for likelihood are defined as follows:
Almost certain – expected to occur every year
Likely – expected to occur at least once every five years
Possible – might occur at some time
Unlikely – such events are known to have occurred on a worldwide basis but only a few times
Rare or Unknown – may occur only in exceptional circumstances; OR it is currently unknown how often the incident will occur
Categories for consequences are defined as follows:
Not significant – no long-term effect on individuals or populations
Minor – individuals are adversely affected but no effect at population level
Moderate – population recovery stalls or reduces
Major – population decreases
Catastrophic – population extinction
17
Table 3. Australasian Bittern Residual Risk Matrix
Likelihood of Consequences occurrence
Not Minor Moderate Major Catastrophic significant
Almost certain Livestock Reduced Reduced overgrazing water quality wetland availability due to changed water flows
Loss of wetlands
Likely Predation Climate variability and change
Possible Fire
Invasive herbivores
Unlikely
Rare or Low genetic Unknown diversity
POPULATIONS UNDER PARTICULAR PRESSURE
The actions described in this recovery plan are designed to provide ongoing protection for Australasian Bitterns throughout their Australian range. The meta-population structure of the species is largely unknown. Australasian Bitterns persist as at least two isolated, subpopulations in eastern and south western Australia. In recent decades, numbers in the previous strong-holds in the Murray-Darling Basin have declined, perhaps permanently due to pressure on water resources and thus now only rare inundation of floodplains. The Western Australian subpopulation has become more restricted with few records away from the south and south-east coasts and Lake Muir wetlands (Pickering 2013). There have been few confirmed records from the
18 Swan Coastal Plain since 1992 and surveys in 2007 and 2008 found that half the wetlands that supported the species in 1980 now retained no suitable habitat (Pickering and Gole 2008; Pickering 2013; DBCA 2018). Breeding in South Australia is confirmed from the Bool Lagoon, and the coast from Adelaide to Victorian border. There are few recent Queensland records (Barrett et al. 2003).
All subpopulations covered by this plan have restricted distributions and small population sizes, which present significant challenges for their recovery and exert strong pressures on their survival in the wild. Given these challenges, all subpopulations of Australasian Bittern covered by this plan require strong protective measures.
In Western Australia, the Department of Biodiversity, Conservation and Attractions have approved a state recovery plan for Australasian Bittern. The population is estimated to be between 50 – 100 individuals. Actions relating to the Western Australian subpopulation should consider both the national and state recovery plans in parallel when implementing research and management actions.
19 RECOVERY PLAN VISION, OBJECTIVES AND STRATEGIES
Long-term Vision The Australasian Bittern population has increased in size to such an extent that the species no longer qualifies for listing as threatened under any of the Environment Protection and Biodiversity Conservation Act 1999 listing criteria.
Recovery Plan Objective The objective of this recovery plan is to demonstrate, by 2030, an increasing trend in the number of mature individuals being recorded in annual surveys at key locations compared to 2020 baseline assessment, and habitat critical to the survival is being managed to meet the ecological requirements of the Australasian Bittern.
Strategies to achieve objectives 1. Implement management strategies to reduce threats to Australasian Bittern and their habitat
2. Enhance protection, improve the quality and increase the extent of suitable habitat for the Australasian Bittern
3. Improve knowledge of the biology and ecology of Australasian Bittern and implement a monitoring strategy to identify population trends
4. Increase stakeholder participation in Australasian Bittern conservation and management
5. Coordinate, review and report on recovery process
ACTIONS TO ACHIEVE THE SPECIFIC OBJECTIVES
Actions identified for the recovery of Australasian Bittern are described below. It should be noted that some of the objectives are long-term and may not be achieved prior to the scheduled five-year review of the recovery plan. Priorities assigned to actions should be interpreted as follows:
Priority 1: Taking prompt action is necessary in order to mitigate the key threats to Australasian Bittern and also provide valuable information to help identify long-term population trends.
Priority 2: Action would provide a more informed basis for the long-term management and recovery of Australasian Bittern.
20 Priority 3: Action is desirable, but not critical to the recovery of Australasian Bittern or assessment of trends in that recovery.
Strategy 1 – Implement management strategies to reduce threats to Australasian Bittern and their habitat
Action Description Priority Performance Criteria Responsible Indicative Agencies Cost and potential partners 1a Ensure water 1 • Long-term water management Australian Core management plans have been updated to include Government government planning specific environmental water business incorporates requirements (i.e. timing, depth, State requirements duration and frequency) for the Governments of the Australasian Bittern, and ensured Industry Australasian that:
Bittern - Stakeholders are aware of key Recovery wetlands for the protection of Team Australasian Bittern habitat Private - Latest science and other landholders information is regularly disseminated to managers and other stakeholders
- Managers in catchments with known Australasian Bittern habitat are aware of the species’ water requirements and have considered their requirements in environmental flow assessments
1b Work with 1 • All levels of governments and Australian Core governments irrigators have implemented Government government and irrigators adequate environmental flows into business to maintain or known Australasian Bittern habitat State improve water Governments management • Irrigators and governments have Industry into known developed or upgraded
Australasian infrastructure (e.g. regulators, Recovery Bittern habitat pumps) to support environmental water delivery into priority habitat Team
• Population responses to Private environmental flows have been landholders monitored and evaluated, and new knowledge has been incorporated into improved management plans
21 1c Monitor, and 1 • Water level data loggers and Australian $125,000 adaptively rainfall gauges have been installed Government pa manage in wetlands that are important to changes to Australasian Bitterns to ensure State hydrology and appropriate water levels are Governments water quality maintained for the species Industry • Changes to hydrology that may result in adverse changes to water Academic levels, salinity, sedimentation or institutions pollution in known habitat have been mitigated Recovery Team • Adverse changes to hydrology and water chemistry have been avoided through adequate buffer zones of vegetated freshwater wetlands in key locations for Australasian Bitterns
• Runoff and drainage into peri-urban wetlands has been managed to support known or potential habitat for Australasian Bitterns
1d Develop and 2 • An ongoing eradication or control State $175,000 implement a program of invasive species at all Governments pa management major breeding areas has been plan to control prioritised and implemented Industry the adverse impacts of • The response of Australasian Traditional invasive Bitterns to the control efforts has Owners predators been monitored including Academic foxes, pigs institutions and cats in known NGOs breeding habitat 1e Develop and 3 • A fire management strategy for the State $125,000 implement a protection of Australasian Bittern Governments pa fire habitat has been developed and management implemented, including the use of Industry strategy for fire as a management tool to the maintain the diversity of reeds and Traditional maintenance rushes where appropriate Owners of Australasian • Traditional burning practices have Academic Bittern habitat been developed that consider the institutions ecological requirements of Australasian Bittern in known NGOs hotspots
22 • Wetlands known to support Australasian Bitterns have been protected from fire during hazard reduction burn activities
• The outcomes of fire management on Australian Bitterns and their habitat have been monitored and evaluated, and incorporated into updated management plans as necessary
1f Minimise the 1 • Where livestock grazing occurs in State $150,000 impacts of Australian Bittern habitat, land Governments pa overgrazing managers have used an appropriate management regime Industry and stocking density that does not detrimentally affect this species’ Traditional habitat Owners
• Where appropriate, grazing Academic pressure has been managed institutions through exclusion fencing or other barriers, at key sites for NGOs Australasian Bitterns
1h Promote 1 • Irrigators in rice-growing areas are Industry $50,000 ‘bittern- aware of Australasian Bittern use of friendly’ channels as foraging and roosting irrigation habitat channel management • The use of pesticides and inappropriate slashing in channels used by Australasian Bitterns has been discouraged
1i Develop 2 • Voluntary Codes of Practice have Australian $80,000 voluntary been developed, incorporating best Government Codes of practice management of Practice, to Australasian Bittern habitat across State promote and all agricultural sectors Governments encourage Industry the • Material on Australasian Bitterns,
conservation best practice management for their NGOs of conservation and voluntary Codes
Australasian of Practice has been provided to Recovery Bittern habitat agricultural communities within the Team in agricultural species distribution
regions • Efforts have been focussed on Private promoting restoration of agricultural landholders areas that historically contained
23 high quality Australasian Bittern habitat
• Engagement with local landholders has resulted in improved management of Australasian Bittern habitat
24 Strategy 2 – Enhance protection, improve the quality and increase the extent of suitable habitat for the Australasian Bittern
Action Description Priority Performance Criteria Responsible Indicative Agencies Cost and potential partners 2a Identify 1 • Existing information has been Recovery $25,000 subpopulations reviewed to identify important Team of high subpopulations that require conservation management intervention priority
2b Identify key 1 • A scientifically-robust process has Recovery $25,000 locations that been undertaken to identify Team are a priority specific wetlands which function as for improved ‘key locations’ for the support and habitat maintenance of healthy protection in Australasian Bittern populations order to (i.e. areas of high-quality habitat support and with high Australasian Bittern maintain densities) healthy populations • Locations have been ranked in terms of population and habitat health, and key locations have been prioritised for potential increased habitat protections
• Models have been used to identify critical wetlands under different climatic and watering conditions
• Wetlands critical for Australasian Bitterns have been accurately mapped and are available to relevant stakeholders and land managers
2c Protect areas 2 • Unprotected Commonwealth and Australian Core of ‘habitat state owned land in areas of Government government critical for ‘habitat critical for survival’ for business survival’ not Australasian Bittern have been State currently identified Governments managed for
nature • Management plans have been conservation developed to maximise conservation values of the identified sites
25 • Consideration has been given to formal protection and adequate resourcing for management for sites where appropriate (i.e. through new conservation reserves, national parks, other protected areas)
2d Develop and 1 • Mechanisms for protecting habitat Australian $120,000 implement a and enhancing wetland restoration Government pa range of on private land, such as voluntary conservation covenants or other State incentives for voluntary landholder incentives, Governments protecting have been identified and promoted Industry Australasian
Bittern habitat • Private landholders who wish to Traditional on private land protect and restore freshwater wetlands with habitat suitable, Owners especially in regions near existing Australasian Bittern habitat, have NGOs been supported to do so Private • The establishment of a network of landholders wetland reserves has been encouraged in agricultural landscapes
2e Undertake 1 • Historical habitat has been Australian $250,000 wetland identified and prioritised for Government pa restoration restoration activities, to State create suitable • Restoration activities designed to Governments habitats for create new bittern-friendly Industry Australasian wetlands, such as fencing and
Bitterns. revegetating seasonally flooded paddocks on private land, have Traditional been implemented Owners
• Best practice guidelines for urban NGOs expansion, storm water management/wetlands have been Recovery developed Team
• Restored sites for Australasian Private Bittern have been monitored for landholders use
• Landholder participation in restoration activities has increased over the life of the recovery plan.
26
Strategy 3 – Improve knowledge of the biology and ecology of Australasian Bittern and implement a monitoring strategy to identify population trends
Action Description Priority Performance Criteria Responsible Indicative Agencies Cost and potential partners 3a Design and 1 • A standardised survey technique Recovery $125,000 implement a suitable for across the species’ Team pa long-term range has been developed monitoring program • Monitoring has occurred annually at key locations and a minimum of every three years at other locations, using a standardised surveying protocol and survey effort
• Population trends have been monitored annually for key locations and, where possible, other locations as data becomes available
• Understanding of the recovery trajectory of monitored populations, and responses to management interventions, has increased
3b Analyse 1 • Knowledge on the population Academic $25,000 survey data to trends has increased institutions increase understanding • Baseline measures of current BirdLife of population population size, and age structure Australia dynamics (e.g. are identified and dispersal rates population have been assessed NGOs size, age cohort, dispersal rates) 3c Maintain a free 2 • A free and openly available central Australian $50,000 and openly repository for reporting Government available observations, such as the BirdLife database for Australia’s Birdata, has been State population, identified Governments habitat and Industry distributional • Relevant government databases
data have been maintained and updated on a regular basis BirdLife Australia
27 • Databases have been integrated to NGOs capture national population, habitat and distributional information for Recovery the species Team
3d Undertake 1 • Knowledge of breeding success, BirdLife $125,000 research on survival and causes of mortality Australia pa breeding have improved success, NGOs survival and • Causes and extent of predation on causes of Australasian Bittern have been Traditional mortality identified and response strategies Owners developed Academic institutions • New information has been generated for all subpopulations
3e Undertake 1 • Techniques to track movements BirdLife $125,000 research on have been refined and trialled Australia pa local and long distance • Knowledge of movements has NGOs movements improved through the Academic institutions landscape • New information has been generated for all subpopulations 3f Determine diet 3 • Knowledge of diet has improved BirdLife $125,000 and prey Australia pa availability in • Prey availability has been wetlands determined at key sites NGOs supporting Academic Australian • New information has been institutions Bittern generated for both subpopulations
3g Determine the 2 • Knowledge of the population BirdLife $125,000 population structure has improved Australia genetic structure • New knowledge has been NGOs across its incorporated into decisions on range management interventions Academic institutions
28 Strategy 4 - Increase stakeholder participation in Australasian Bittern conservation and management.
Action Description Priority Performance Criteria Responsible Indicative Agencies Cost and potential partners 4a Develop broad 2 • Australasian Bitterns are State $80,000 pa promotional considered a flagship species for Governments material to encouraging healthy wetland raise management across their range Regional awareness NRM bodies about the • The important ecosystem functions Australasian of wetlands, and their aesthetic Industry Bittern and recreational values, have been promoted to increase the interest Traditional of conservation groups and Owners general public in their protection and restoration BirdLife Australia • Informative material, such as fact sheets and brochures, on NGOs Australasian Bittern ecology and conservation and the importance of Recovery protecting vegetated freshwater Team wetlands have been developed
• Materials have been shared with government agencies, irrigation industry bodies, conservation groups, landholder, industry groups and the general public
• Strong partnerships have been built between all levels of local, state and Commonwealth government agencies, NRM bodies and community groups interested in progressing conservation actions for the Australasian Bittern
4b Develop 2 • Targeted fact sheets have been State $80,000 pa targeted fact produced and distributed to Governments sheets for landholders landholders Local • Landholder awareness of Governments Australasian Bitterns increases and wetland management has Regional improved as a result NRM bodies
• Private landholders, and land Industry managers have contributed to implementing conservation actions BirdLife Australia
29
NGOs
Recovery Team
4c Develop 2 • Best practice rice growing Industry $100,000 ‘bittern friendly’ guidelines have been developed rice for the benefit of Australasian BirdLife management Bitterns Australia practices • An increased number of rice NGOs growers have given consideration to growing ‘bittern friendly’ rice
• ‘Bittern friendly’ rice is a nationally recognised brand that supports the conservation of Australasian Bitterns
4d Support and 1 • An Australasian Bittern Field Regional $125,000 train Manual has been developed NRM bodies pa volunteers to monitor • The manual has been Traditional Australasian disseminated and used in Owners Bittern conjunction with state agencies, landholders, industry groups and BirdLife community volunteers Australia
• Annual training sessions have NGOs been undertaken with interested stakeholders and community volunteers in order to achieve ‘best practice’ in terms of Australasian Bittern management
30 Strategy 5 – Coordinate, review and report on recovery process
Action Description Priority Performance Criteria Responsible Indicative Agencies Cost and potential partners 5a Establish and 1 • A National Recovery Team All Core maintain a has been established within government National Recovery the first six months of the business Team for the making of the recovery plan Australasian Bittern • The Recovery Team has coordinated, reviewed and reported on the recovery outcomes for the life of this plan
5b Approve Recovery 1 • Terms of Reference for the Recovery Core Team governance Recovery Team have been Team government arrangements approved in accordance with business national best practise guidelines
• The Recovery Team has been registered nationally 5c Submit annual 1 • Recovery Team annual Recovery Core reports on reports have been submitted Team government progress against each year in accordance business recovery actions with the national reporting framework 5d Review the 1 • In consultation with relevant Recovery $10,000 recovery plan five stakeholders, a five review of Team years after making the recovery plan has been endorsed by the Recovery Team 5e Facilitate 1 • A communication network Recovery $30,000 knowledge between interested Team exchange and stakeholders has been awareness established between Australian, New • Meetings between site Zealand and New managers has occurred at Caledonian land least biennially to share managers, knowledge and experience researchers and decision makers • A researcher network has been established and exchange visits have occurred between stakeholders of Australasian Bittern populations
31
DURATION AND COST OF THE RECOVERY PROCESS
It is anticipated that the recovery process will not be achieved prior to the scheduled five year review of the recovery plan. The ‘National Recovery Plan for the Australasian Bittern (Botaurus poiciloptilus)’ will therefore remain in place until such time as the populations of Australasian Bittern have improved to the point at which the population no longer meet threatened species status under the EPBC Act.
The cost of implementation of this plan should be incorporated into the core business expenditure of the affected organisations, and through additional funds obtained for the explicit purpose of implementing this recovery plan. It is expected that state and Commonwealth agencies will use this plan to prioritise actions to protect the species and enhance its recovery, and that projects will be undertaken according to agency priorities and available resources. All actions are considered important steps towards ensuring the long-term survival of the species.
Table 3: Summary of recovery actions and estimated costs in ($000’s) for the first five years of implementation (these estimated costs do not take into account inflation over time).
Action Cost Year 1 Year 2 Year 3 Year 4 Year 5 Total Strategy 1 $625,000 $655,000 $575,000 $575,000 $575,000 $3,005,000 Strategy 2 $425,000 $375,000 $375,000 $375,000 $375,000 $1,925,000 Strategy 3 $550,000 $500,000 $500,000 $500,000 $525,000 $2,575,000 Strategy 4 $285,000 $385,000 $285,000 $285,000 $285,000 $1,525,000 Strategy 5 $10,000 $0 $10,000 $0 $20,000 $40,000
TOTAL $1,895,000 $1,915,000 $1,745,000 $1,735,000 $1,780,000 $9,070,000
32
EFFECTS ON OTHER NATIVE SPECIES AND BIODIVERSITY BENEFITS
The Recovery Plan focuses on the management, protection, restoration and creation of freshwater and coastal wetlands, the principal breeding habitat for Australasian Bittern. Australia has a diverse waterbird fauna adapted to these wetlands, many of which are unpredictable in their availability and habitats (Kingsford and Norman 2002). Many waterbird species exploit the high productivity of those wetlands that dry out after being inundated temporarily (Taylor 2003). Consequently, appropriate management of these wetlands will benefit many plant and animal species, as well as associated ecological communities.
The wide distribution and unpredictable nature of freshwater and coastal wetlands makes it difficult to identify population trends of species within them. Other threatened species occur in these habitats, such as the Australian Painted Snipe (Rostratula australis), which can have conflicting habitat requirements for targeted management (Herring and Silcocks, 2014; Herring et al. 2019). The Australasian Bittern, an unusually attractive and enigmatic resident waterbird, may be of value as a flagship species to highlight the importance of conserving these habitats.
SOCIAL AND ECONOMIC CONSIDERATIONS
Wetlands are a vital element of national and global ecosystems and economies. At the most fundamental level, wetlands are a key part of the water cycle, playing critical roles in maintaining the general health of Australia’s rivers, estuaries and coastal waters. Wetlands protect our shoreline from wave action, mitigate the impacts of floods, absorb pollutants and provide habitats for animals and plants, including a number of species that are threatened. Wetlands are also critical to maintaining and improving our quality of life. They provide tangible benefits to the Australian economy, such as employment opportunities. Wetlands purify our water and are a focal point for recreational activities. They form nurseries for fish and other freshwater and marine life and, as such are of critical importance to Australia’s commercial and recreational fishing industries. In some areas, wetlands support grazing, forestry and cropping activities.
As habitats critical to the survival of the species’ are identified, there is potential for developments to be restricted under the EPBC Act development assessment and approval process. This may include increased costs due to the assessment processes, requirements to provide offset funding to secure or rehabilitate habitat, or for other threat mitigation work.
Restrictions on further development of wetland habitat may impact on some landowners, other land managers and developers. These restrictions may not significantly impact on agricultural or irrigation industries since many of the suitable areas have already been developed and the remaining critical habitats are generally located in protected conservation areas and remote locations. These areas are, therefore, relatively less attractive for further development.
A large network of community volunteers across Australia actively participate in BirdLife Australia’s coordinated annual surveys for migratory shorebirds and wetland birds. Involvement can provide social benefits with community members and engaged groups having a sense of achievement, inclusion, community spirit and pride whilst gaining enjoyment and appreciation of their surrounding natural environment. The community education components of the program also promote community ownership, provide community support and encourage active involvement in protecting local natural resources. Additional social benefits include encouraging passive recreation, appreciation of natural aesthetic values and increased awareness and appreciation of Indigenous cultural values.
33 AFFECTED INTERESTS
Organisations and individuals likely to be affected by the actions proposed in this plan include: government agencies (Commonwealth, state and territory, local), particularly those involved with wetland environments and conservation programs; private landholders; Indigenous land and sea management groups (including ranger programmes); researchers; bird watching groups; conservation groups; wildlife interest groups; 4WD and fishing groups; environmental consulting companies; tourism operators; industry and commercial bodies; and, proponents of agricultural development in the vicinity of important habitat. However, this list should not be considered exhaustive, as there may be other interest groups that may like to be included in the future or need to be considered when specialised tasks are required.
The following table lists some of the interest groups, how they could contribute to the success of the plan and the potential benefits/impacts that may emerge from the Plan’s implementation:
Interest Group Contribution Impacts/Benefits Australian Government Responsible for development, Informed decision making regarding the EPBC coordination and evaluation of the Act referral and assessment process plan Greater ability to deliver on domestic and Responsible for implementation of the international obligations with regard to plan in Commonwealth areas biodiversity conservation Subject to available resources, providing financial support for Increased knowledge of the Australasian implementation of the plan Bittern and their habitats – increased exchange of information between decision makers and the community State and territory government agencies Contributing to the development of the Greater ability to deliver on state obligations plan with regard to biodiversity conservation Potential implementation of the plan Increased knowledge of the Australasian within jurisdictional boundaries Bittern and their habitats – increased exchange of information Local Government Contributing to the development of the Increased knowledge of the Australasian plan and taking the plan into Bittern and their habitats – increased exchange consideration when reviewing of information planning schemes Enhanced ability to deliver obligations with Potential implementation of on ground regard to biodiversity conservation activities within jurisdictions Supports local tourism industry Natural Resource Management (NRM) Integrating the plan into NRM regional Increased awareness of regional importance of regional bodies plans important habitat sites. Informing managers of Opportunity to deliver on-ground biodiversity values activities Opportunity to seek funding for conservation projects under biodiversity conservation programs Land councils and Traditional Owners Contributing to the development of the Increased knowledge of the Australasian Bittern and their habitats – increased exchange Including those that have co-management or plan and development and of information sole management responsibilities for implementation of site management Opportunity to seek funding for conservation important habitats. plans – research and monitoring activities – contributing traditional projects and achieve ownership of projects knowledge Develop research partnerships with scientists and the community Develop traditional burning practices that consider the ecological requirements of Australasian Bittern
34 Interest Group Contribution Impacts/Benefits Conservation Groups Contributing to the implementation Opportunity to seek funding for conservation and evaluation of the plan, particularly and awareness projects under biodiversity in conducting research and monitoring conservation programs programs – implementing on ground Greater coordination of targeted conservation activities projects Delivering on charitable/not-for-profit goals benefiting the public
Community and Special Interest groups Contributing to the plan and More Australasian Bitterns to enjoy volunteering for conservation activities Opportunity to participate in conservation – implementing on ground activities projects Researchers Contributing to the implementation Increased exchange of information – and evaluation of the plan opportunity to seek funding for research Opportunity to establish collaborations within Australia and internationally Recreational users of sites – recreational Contributing to the development of the Some leisure activities that affect important fishers, field and game groups. plan habitat sites may need to be managed These groups will be one of the main recipients for education and awareness activities that focus on how they may continue their activities and contribute to the conservation of seabirds at the same time Landholders Contributing to the development and These groups will be the target of education and awareness activities. Particularly on how implementation of the plan site management plans may be implemented by landholders Opportunity to build voluntary incentives into the plan for landholders to comply with recommendations Enhance certainty with regard to EPBC referrals Commercial users of sites or surrounding Contributing to the Plan and These groups will also be one of the main area – agriculture, salt mining, commercial implementing measures that minimise recipients for education and awareness fisheries, farmers (surrounding land use), the impact of their operations on activities, although theirs will focus on airports, maritime ports, renewable energy waterbirds minimising the impacts of their operations on infrastructure, tourism operators the Australasian Bittern and the habitats on which they depend Enhance certainty with regard to EPBC referrals
CONSULTATION
The Recovery Plan for the Australasian Bittern has been developed through extensive consultation with a broad range of stakeholders. The consultation process brought together key species experts and conservation managers, from a range of different organizations, to categorize ongoing threats to the Australasian Bittern, and identify knowledge gaps and potential management options. Consultation included representatives from government agencies, non-government organisations, researchers and local community groups. During the drafting process the Department of the Environment and Energy (Cwlth) continued to work closely with key stakeholders.
Notice of the draft plan was made available for public comment for three months between [DATE] and [DATE]. Any comments received that were relevant to the survival of the species were considered by the Threatened Species Scientific Committee as part of its assessment process.
35 ORGANISATIONS/PERSONS INVOLVED IN EVALUATING THE PERFORMANCE OF THE PLAN
This plan should be reviewed no later than five years from when it was endorsed and made publicly available. The review will determine the performance of the plan and assess:
• whether the plan continues unchanged, is varied to remove completed actions, or varied to include new conservation priorities; or
• whether a recovery plan is no longer necessary for the species’ as either conservation advice will suffice, or the species’ are removed from the threatened species list.
As part of this review, the listing status of the species’ will be assessed against the EPBC Act species listing criteria.
The review will be coordinated by the Department of the Environment and Energy in association with relevant Australian and state government agencies and key stakeholder groups such as non-governmental organisations, local community groups and scientific research organisations.
Key stakeholders who may be involved in the review of the performance of the Recovery Plan for the Australasian Bittern, include organisations likely to be affected by the actions proposed in this plan and are expected to include:
Australian Government Department of the Environment and Energy
State/territory governments Department of Planning and Environment (NSW) Department of Environment, Land, Water and Planning (Vic) Department of Environment and Water (SA) Department of Primary Industries, Parks, Water and Environment (Tas) Department of Biodiversity, Conservation and Attractions (WA) Natural resource management bodies in coastal regions Local government in coastal regions
Non-government organisations BirdLife Australia Local conservation groups Local communities Private landholders Indigenous communities Universities and other research organisations Industry Recreational sports and associations Recreational fishers and associations Recreational boaters
36 REFERENCES
Barrett, G., Silcocks, A., Barry, S., Cunningham, R. and Poulter, R. (2003) The New Atlas of Australian Birds. Melbourne, Victoria: Birds Australia.
Belcher, C., Borrell, A., Davidson, I. and Webster, R. (2017) Australasian Bittern Surveys in the Murray Valley and Barmah National Parks 2016- 2017. Unpublished Report by New South Wales National Parks and Wildlife Service, Sydney.
BirdLife International (2019) Botaurus stellaris. The IUCN Red List of Threatened Species 2016: e.T22697346A86438000. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22697346A86438000.en. Downloaded on 13 September 2019.
Birds Australia (2009). Important Bird Areas online database. Available on the Internet at: http://www.birdata.com.au/ibas
Birds Australia (2009). Personal communication by letter, 26 March 2009. Carlton, Victoria.
Birds Australia (2010). Australasian Bittern Botaurus poiciloptilus National Population Estimates for Spring – Summer 2009–10. In possession of Birds Australia, Carlton.
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