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The Cranes

Status Survey and Conservation Action Plan

Brolga

(Grus rubicundus)


JPG-Brolga

Subjects:
Summary
Subspecies/populations
Population Numbers and Trends
Conservation Status
Historic and Present Distribution
Distribution by Country
Habitat and Ecology
Principal Threats
Current Conservation Measures
Priority Conservation Measures

Summary

The Brolga occurs throughout northern and eastern Australia and in limited areas of New Guinea. The Brolgas in northern and southern Australia can be regarded as discrete populations, but are no longer recognized as distinct subspecies. No systematic, range-wide surveys of the species have been undertaken, and so populations estimates and trends are poorly understood. The total population may range from 20,000-100,000 and is probably stable overall. The species still occupies much of its historic range. In recent decades, the Brolga has declined in southeastern Australia, while apparently expanding (due to increasing used of croplands) in the Northern Territory, the Kimberleys, and other portions of western Australia. Little is known about the status of or trends in the New Guinea populations. The species is classified as Lower Risk under the revised IUCN Red List criteria.

Brolgas are non-migratory, but do move in response to seasonal rains. Ecologically, they are perhaps the most opportunistic of the cranes, having evolved to cope with Australia’s extreme climatic variations. Northern populations are concentrated during the dry season in coastal freshwater wetlands, where they subsist on the tubers of the bulkuru sedge (Eleocharis dulcis). In the wet season, they disperse to breeding territories in freshwater and brackish marshes, wet meadows, and other seasonal wetlands. Although the wet and dry seasons in southern Australia are less marked, southern Brolga populations also move between wet season breeding territories and traditional dry season flocking areas. They use a similarly wide range of available wetland types, but generally use salt marshes far less than the northern Brolgas.

The most significant threat to the Brolga across its range is the loss and degradation of wetland habitats. In northern Australia (especially along the eastern coast), wetlands used by Brolgas are extensively degraded as a result of heavy livestock grazing, disruption of hydrological processes, and changes in vegetation. In the south, loss of wetlands to drainage and reclamation for agriculture is probably the main factor behind the dramatic decline in the number of Brolgas occurring there. Other threats include the subdivision (and subsequent fencing) of large private landholdings, predation by the introduced red fox, incidental poisoning, and collisions with utility lines.

Most research and conservation activity involving the Brolga has taken place in the southeast, where the species is no longer as common as in the north. Conservation measures undertaken for the species include: legal protection throughout Australia; local surveys in South Australia, Victoria, and New South Wales; preparation of an Action Statement for Brolgas under the Victorian Flora and Fauna Guarantee Act; programs to protect and restore privately owned wetlands in Victoria; and establishment of a private conservation organization, Friends of the Brolga. A captive propagation program was instituted in Victoria in 1964. Surplus birds from this program are to be released on a one-time-basis in 1995 and 1996.

Priority conservation needs include: adoption of stronger watershed-level approaches to wetland protection and restoration; assessment of the status and conservation needs of the species in New Guinea; enactment of stronger national wetland protection laws and policies; development of incentive and extension programs to encourage and reward private landowners who conserve Brolga habitat; development of a systematic censusing and monitoring program for the species, and inclusion of the species in routine aerial waterfowl counts; expanded research on flocking sites, breeding biology, size and trends in the total population, and the occurrence of isolated populations; and expanded education and extension programs.

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Subspecies/populations

There are no subspecies. The species was formerly divided into two subspecies: the Northern Australian Crane (G. r. argentea) and the Southern Australian Crane (G. r. rubicundus). This division is no longer accepted by most crane biologists. However, several factors do justify regarding the northern and southern Brolgas as separate populations. They are adapted to different breeding (wet) seasons. They are separated by an extensive area of unsuitable habitat, and because seasonal movements are limited, the northern and southern birds interact minimally. There may be some morphological differences between the birds of the north and the south. These factors may be significant, and should be taken into account in planning conservation measures (A. Haffenden pers. comm.). DNA analysis may confirm these distinctions between northern and southern birds.

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Population Numbers and Trends

Population Number Trend Source
Northern Australia 20,000-100,000     Generally stable P. DuGuesclin pers. comm.,
R. Jaensch pers. comm.,
A. Haffenden pers. comm.
Southern Australia     approx. 1000     Stable to declining     White 1987, 1992
New Guinea Unknown Unknown
Total 20-100,000 Generally stable;
possibly declining    
in SE Australia

A lack of systematic surveys, especially in northern Australia, makes population estimates for the Brolga highly uncertain. Several northern sites are known to hold seasonal concentrations of thousands of Brolgas, and 20,000 is presumed to be the minimum for the species. The total is likely to be much higher, although even reasonable estimates should be regarded essentially as guesswork at this point (R. Jaensch pers. comm., A. Haffenden pers. comm.).

The population in southern Australia has not been surveyed. White (1987) provided a “conservative estimate” of 600-650 Brolgas in Victoria. A total of 635 birds were recorded during a 1992 census of Victoria (White 1992). The present estimate assumes additional birds in the region, but should be regarded as a general figure.

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Conservation Status

Species
IUCN category Lower Risk (least concern)
CITES Appendix II
    
Population IUCN Category
Northern Australia     Lower Risk (least concern)
Southern Australia Vulnerable, under criteria
C1b,c   D
New Guinea Data Deficient

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Historic and Present Distribution

GIF-Distribution Map

The Brolga occurs only in Australia (not including Tasmania) and limited areas of New Guinea (Lavery and Blackman 1969, Blakers et al. 1984, Coates 1985, Marchant and Higgins 1993). It has been reported as an occasional or accidental visitor in New Zealand (Walkinshaw 1973). They are non-migratory, but do move in response to seasonal rains.

The species continues to occupy most of its historic range. Since the 1800s, however, the population has retracted from former strongholds in southeast Australia, while apparently expanding into cultivated areas in the Northern Territory, the Kimberleys, and other areas of western Australia (Pizzey 1980, Johnsgard 1983, Blakers et al. 1984). The range of the Brolga overlaps that of the Sarus Crane in northern Queensland and in the extreme northern portions of the Northern Territory and Western Australia (Blakers et al. 1984, Archibald and Swengel 1985, R. Jaensch pers. comm.).

Within Australia, Brolgas are found in both the wet-dry tropics of the north (Western Australia, Northern Territory, and Queensland) and the southern temperate regions (eastern South Australia, Victoria, and portions of New South Wales) (Marchant and Higgins 1993). Through most of this range, Brolgas are relatively uncommon and widely dispersed. They are most abundant in northeastern Australia, where they are relatively free of competition from magpie geese (Anseranas semipalmata) for their preferred food, the tubers of bulkuru sedge (Eleocharis dulcis) (Lavery and Blackman 1969, Blakers et al. 1984, H. Lavery pers. comm.). During the dry season and droughts, northern Brolgas gather into flocks at freshwater coastal and inland marshes. Concentrations of several hundred birds can occur at the most favorable sites (Storr 1977, 1980). When rains return in the north (November-April), the Brolgas disperse widely to breeding territories (Pizzey 1980). The northern populations of the Brolga apparently began to expand into Western Australia in the 1920s, and have continued to increase there, especially since the early 1950s (Serventy and Whittell 1967).

The Southern population of the Brolga has declined significantly since European settlement. In Victoria, at the southernmost extent of its range, the greatest range reductions occurred from the 1890s to the late 1940s (White 1987). Brolgas were found in the plains and wetlands around Melbourne until the early 1900s; on French Island in Western Port Bay until 1919; on the coastal plains of east Gippsland until the 1920s; in the Rutherglen district of northeast Victoria until the early 1960s; and in the Corryong District of northeast Victoria until the mid-1970s (White 1987, Hill 1992, P. Du Guesclin pers. comm.).

As a result of these range reductions, the Southern population of the Brolga is now small and fragmented, and relies on smaller (often protected) wetlands. These losses were significant in that they separated, and perhaps isolated, the southern flocks from the large flocks of northern Australia (White 1987). In Victoria, the Brolga has been listed as rare by Ahern (1982) and Baker-Gabb (1991), and in 1991 was classified as threatened under the state’s Flora and Fauna Guarantee Act. Brolgas continue to breed in southwestern Victoria, southeastern South Australia, and to a lesser extent in west Wimmera in central and northeast Victoria. Breeding also occurs in isolated and restricted areas with suitable habitat in New South Wales (e.g., Macquarie Marshes and the Denilquin area) (P. Du Guesclin pers. comm., D. White pers. comm.).

In New Guinea, the Brolga occurs in the southern lowlands, with a smaller population possibly resident along the north-central coast in the Sepik River Basin (Mayr 1941, Coates 1985). The extensive wetlands in the south have apparently supported healthy crane populations in the past, but little is known about the historical trends or current size and distribution of this population (Johnsgard 1983, Coates 1985). The population probably occurs mainly in the coastal floodplains (e.g., of the Bensbach River area), although recent observations have been purely anecdotal (R. Jaensch pers. comm.). It is possible that Brolgas from northeastern Australia retreat to New Guinea for refuge during periods of extended drought. Such movements have been noted among several other species of Australian waterbirds (H. Lavery pers. comm.).

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Distribution by Country

Australia R
Indonesia (New Guinea)     R
New Zealand V
Papua New Guinea R
    
R = Permanent resident
V = Vagrant

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Habitat and Ecology

JPG-Tubers of bulkuru sedge and Brolga droppings

Marchant and Higgins (1993) provide a comprehensive review of information on the habitat, ecology, diet, movement, and behavior of the Brolga. Of the fifteen species of cranes, the Brolga is perhaps the most opportunistic and variable in terms of habitat selection. Brolgas have developed physiological and behavioral adaptations to Australia’s diverse climatic conditions, especially its rainfall patterns. Because the northern and southern birds respond to different environmental conditions, they are discussed here separately.

Northern Australia/New Guinea

During the northern dry season (usually June to November), Brolgas are concentrated in coastal freshwater marshes dominated by the bulkuru sedge. These marshes are situated in a narrow zone between the coastal hills and the saltpans and mangrove forests of the coast edge. The Brolgas gather in large flocks and dig holes in the drying mud to extract bulkuru tubers, the main item in their dry season diet. Other wetland types (freshwater lagoons, tidal and riparian pools, inland marshes, lake edges, irrigated pastures and fields) as well as grasslands and croplands are also used (Lavery and Blackman 1969; Walkinshaw 1973; Storr 1977, 1980). In addition to tubers, the Brolga diet includes other wetland plants, upland plants (including cereal grains), insects, freshwater and saltwater mollusks, crustaceans, and frogs (Lavery and Blackman 1969, Marchant and Higgins 1993).

Breeding season in northern Australia begins in November or December during the “pre-wet.” At this time the Brolgas disperse to breeding areas and select nest sites. Brolgas may nest wherever suitable wetlands exist. Some remain in the large coastal wetlands; a substantial portion of the population in Queensland nests in coastal wetlands around the Gulf of Carpentaria (which extend as far as 50 km inland). Others disperse to inland nesting sites, including both upstream sections of coastal floodplains and wetlands up to several hundred kilometers inland. As the rainy season advances, many small, isolated, ephemeral wetlands become available to them (Blackman 1978). They may also nest at small artificial livestock watering ponds (Lavery and Blackman 1969).

Brolgas begin to nest as water levels rise with the arrival of the “wet” in January. Heavy rains are frequent during this period, and can result in the drowning of the nests of early nesting pairs (Blackman 1978, A. Haffenden pers. comm.). Nests are large (up to 1.5 m in diameter) mounds of grass and sedge stems, built in densely vegetated wetlands. Egg-laying peaks in February-March. Usually two eggs are laid. Among both northern and southern birds, incubation takes 28-31 days and chicks fledge at about 100 days. By June or July the breeding wetlands are drying, and families begin to move back toward coastal areas to re-form flocks. Timing and distance of these movements can vary, depending on annual rainfall amounts. Loss of habitat has also had an impact on movement patterns, especially along Australia’s east coast, where wetlands have been widely converted to agricultural production (mainly for corn, rice, sorghum, and pasture grasses).

In Queensland, the ranges of the Brolgas and Sarus Crane overlap (Archibald and Swengel 1987). However, competition between the two species appears to be insignificant at both breeding sites and dry season feeding areas. In the breeding season, Sarus Cranes tend to prefer smaller wetlands in more forested settings, while Brolgas prefer larger, more open wetlands (A. Haffenden pers. comm.). Tubers comprise the main part of the Brolga’s dry season diet, while Sarus Cranes feed primarily on seeds and other surface foods. Sarus Cranes thus tend to avoid the Brolga’s primary habitat, utilizing croplands and other disturbed habitats that Brolgas only use when their preferred habitats are unavailable. It is probable that the two species have always used these habitats in this way, but the phenomenon may now be more obvious due to the spread of cereal crop agriculture in northern Australia (A. Haffenden pers. comm., H. Lavery pers. comm.).

Although information on the habitat and ecological circumstances of the Brolgas in New Guinea is scarce, the habitat characteristics are likely similar to those of the Australian birds (R. Jaensch pers. comm.).

Southern Australia

The Brolga’s habitat in southern Australia is characterized by less extreme patterns of rainfall than in the monsoon-dominated habitats of the north. Wet winters alternate with drier summers, although rain can and does occur at anytime during the summer. The normal breeding season extends from July to December. During this period, Brolgas nest and forage in shallow (<50 cm) freshwater marshes and wet meadows, preferring the former. They also use deeper marshes, shallow lakes, flooded grasslands, brackish wetlands, and other wetland types, but generally use salt marshes far less than the northern Brolgas (Blakers et al. 1984, Arnol et al. 1984).

From December to May, as the dry season advances and wetlands dry out, parents and chicks gather at traditional flocking areas, which include permanent freshwater wetlands and upland foraging areas. During the dry season, Brolgas also use the edges of small reservoirs and lakes, and disperse into a wide range of other habitat types, including not only wetlands but upland pastures, croplands, and other drier habitats (White 1987). They remain in these areas until the rains return again. In May and June, the flocks disperse again to return to their breeding areas.

Bulkuru sedge is not available to the Brolgas south of Brisbane. The diet of the birds in the south is thus more varied, consisting of a wide range of plant, invertebrate, and small vertebrate food items (see Marchant and Higgins 1993).

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Principal Threats

JPG-Pair with chick, Queensland, Australia

In both north and southern Australia, the most significant threat to the Brolga is loss and degradation of wetland habitats. The hydrological processes of many wetlands within the Brolga’s range have been disrupted by intensive livestock grazing and other factors, with both direct and indirect effects on Brolga habitat. Sedimentation due to accelerated soil erosion in upper watersheds affects many wetlands (especially large coastal wetlands in Queensland and other areas of northeastern Australia). At the same time, upstream dams, drainage projects, and water diversions have reduced stream inflow in many wetland systems. These changes have allowed non-wetland grasses and shrubs to invade wetlands, reducing the supply of sedge tubers available to Brolgas. Changes in vegetation may also allow increased predation by providing cover for goannas, foxes, and other predators close to crane nests and chicks (A. Haffenden pers. comm.). The coastal wetlands of northern Australia are also subject to increased saltwater intrusion and invasion by Mimosa pigra, rendering them unsuitable for cranes (R. Jaensch pers. comm).

More directly, many wetlands have been actively drained and managed to expand the area available for grazing and to make these areas more accessible during the wet season. The physical impact of heavy grazing results in earlier and harder drying of wetlands, preventing the cranes from reaching the subsurface tubers. Grazing also promotes invasion of wetlands by non-wetland plants. In many areas (especially northern Australia), feral pigs not only contribute to these changes in habitat, but also seek out the sedge tubers themselves for food. Although the extent of these alterations is not known, it is likely that many smaller wetlands have been severely affected by them (A. Haffenden pers. comm.).

In general, the Northern population has in the past been relatively secure due to the remoteness of the breeding habitat, and the unsuitability of these lands for disruptive farming practices. Moreover, protected areas have included relatively extensive areas of breeding and foraging habitat. Although protected areas continue to be important for the species (especially in the Northern Territory), higher agricultural demand and changing husbandry techniques have led to an increase in disturbance and alteration of prime breeding habitat in Queensland, and a reduction in suitable foraging habitat. This trend is continuing. Although little quantitative work has been undertaken, observational and anecdotal information indicates that fewer Brolgas are being seen in traditional dry season areas on the eastern coast. In some areas, these reductions exceed 50% (A. Haffenden pers. comm.).

In southeastern Australia, reclamation of wetlands for agriculture (along with poisoning, hunting, and egg collecting) are believed to have been the main historical factors contributing to the dramatic decline in Brolga numbers (D. White pers. comm.). In southern Australia, continued loss or modification of freshwater wetlands threatens traditional crane breeding and flocking areas (Arnol et al. 1984). In the 1980s, a 500 kv utility line was built directly through the highest quality breeding habitat remaining in Victoria, resulting not only in direct loss of habitat, but increased risk of collision (White 1987, Goldstraw and Du Guesclin 1991).

In some breeding areas (mainly in southern Australia), the subdivision of large private landholdings with wire fencing has also been a detrimental factor. Cranes can become tangled in fences. In addition, as the size of paddocks has decreased, the effective foraging range of Brolgas with dependent flightless young has been reduced. Chicks in these “enclosed” areas are more vulnerable to predation, starvation, and dehydration. When the nesting areas dry out, unfledged chicks may be unable to follow their parents to nearby wetlands (Arnol et al. 1984). The increasing density of human settlements has also disrupted foraging behavior and seasonal movements of Brolgas throughout coastal Australia (H. Lavery pers. comm.). Other threats to the Brolga include: disturbance and fragmentation of flocks during the waterfowl hunting season; hunting and poisoning of cranes in response to crop depredation (this was more common in the past than at present); incidental poisoning as a result of pest control campaigns; predation by the introduced red fox (Vulpes vulpes); and collisions with utility lines (Arnol et al. 1984).

There is no information available on existing or potential threats to the Brolga in New Guinea.

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Current Conservation Measures

JPG-Dancing Brolgas near Townsville, Australia

International Agreements and Cooperation

Australia and Papua New Guinea are signatories to the Ramsar Convention. Recently, Australian crane and wetland biologists have worked jointly with counterparts from Vietnam to understand the ecological similarities and differences underlying wetland conservation efforts in their respective countries (Beilfuss 1994). This training effort was carried out with the support of the Asian Wetland Bureau, ICF, and the MacArthur Foundation.

Legal and Cultural Protection

The species is protected throughout Australia, although the degree of protection varies from state to state. Cranes cannot be hunted in Queensland, Western Australia, or the Northern Territory. In Queensland and the Northern Territory, a Permit to Take can be issued to farmers if they can demonstrate that Brolgas are causing crop damage. In practice, permits are very rarely (if ever) issued (A. Haffenden pers. comm.). In Victoria, the species is fully protected under the state’s 1975 Wildlife Act. The 1988 Flora and Fauna Guarantee Act requires that a statement of actions for managing the species and its habitat be prepared (this statement has not yet been issued). Brolgas are fully protected in all National Parks where they occur. Aboriginal hunting is allowed in some park lands, as well as on aboriginal lands. Export and translocation of captive Brolgas is strictly regulated by the Australian government.

Protected Areas

Most of the highly significant Brolga habitat (e.g., important breeding areas of the western Cape York Peninsula) occurs on private lands. No protected areas have been dedicated to, or established specifically to protect, Brolgas. However, the species does use many protected areas throughout its range. The Staaten River, Mitchell & Alice Rivers, and Lakefield National Parks (all in Queensland) protect both wet and dry season habitat and have resident breeding populations. Several national parks near Townsville protect important wetland areas, although much of the significant Brolga habitat in the area is held by private landowners. Brolgas occur (although in smaller numbers than in the past) at the Town Common Environmental Park, administered by the Queensland Department of Environment and Heritage. Other protected areas used by Brolgas include: Kakadu National Park (Northern Territory); Parry Lagoons Nature Reserve (Western Australia); Bool Lagoon Conservation Park (South Australia); Lake Ayrey and Lake Cuerang Wildlife Reserves (Victoria); and Tonda Wildlife Management Area (Papua New Guinea) (P. DuGuesclin pers. comm, A. Haffenden pers. comm., R. Jaensch pers. comm.).

Habitat Protection and Management

In general, little habitat protection or management has been undertaken specifically to benefit the Brolga. Some habitat alterations have had incidental positive impacts. For example, the construction of water impoundments has in some cases increased the availability of breeding habitat in the drier portions of the species’ range (e.g., at Lake Argyle in the Kimberley Division of Western Australia).

In southeast Australia, where a significant percentage of wetland breeding habitat has been lost to development, interest in habitat management and restoration is growing. Recent research on nesting habitat requirements provides a basis on which to build management programs, especially programs that involve private landowners (Hill 1992). In the early 1990s, the Victoria Department of Conservation and Environment provided support for conservation projects on private wetlands (e.g., fencing, tree and shrub planting, water level restoration) through a program of Wetland Improvement Grants. Since 1987, the Victorian Conservation Trust (an independent body established by Act of Parliament) has worked with landowners to develop “conservation covenants” that provide long-term protection for conservation values on private land (Forge 1990). Also in Victoria, the Department of Conservation and Environment and Bird Observers Club of Australia have jointly organized a “Land for Wildlife” program. The program encourages the voluntary conservation of wetlands and other wildlife habitats on private lands.

Surveys/Censuses/Monitoring

There are at present no programs to survey or monitor the Brolga population across its entire range. Few surveys have been undertaken in the past, in part because of the presumption that the population is healthy. H. Lavery (pers. comm.) notes that undertaking an accurate census would be “a monumental and impracticable task,” and that the difficulties of such an effort are compounded by crane movements in response to drought and other factors. In the north, there are no regular counts, but some local surveys have been conducted (e.g., Lavery and Blackman 1969, Archibald and Swengel 1987). In Victoria and New South Wales, the nesting areas and numbers of Brolgas have been documented since 1991 by the Friends of the Brolga (see below). The population in New Guinea has never been surveyed.

Research

Recent research on Brolgas has been conducted primarily in South Australia, Victoria, New South Wales, and Queensland. These studies have examined the status and distribution of the Brolga (White 1987); ecology and habitat management requirements (Arnol et al. 1984, Haffenden in prep.); aerial survey methods and population estimates (Blackman 1977); and the breeding population in southeastern South Australia (Bransbury 1991). Banding studies have been carried out on a limited basis in Victoria (Anon. 1992). Hill (1992) collected and analyzed information on Brolga nesting and breeding sites in Victoria, and offered recommendations on how to use this information to establish a database, model breeding habitat, enhance habitat management, and improve census procedures. Archibald and Swengel (1987) studied the interactions and comparative ecology of Brolgas and Sarus Cranes in the shared portions of their ranges. Virtually no field research has been undertaken in the New Guinea portion of the Brolga’s range.

Management and Recovery Plans

In Victoria, where the Brolga has experienced significant declines, the Department of Conservation, Forests, and Lands prepared in 1984 a comprehensive plan, “Management of the Brolga (Grus rubicundus) in Victoria” (Arnol et al. 1984). This document recommended conservation actions in five areas: policy development, extension and advisory services, research, captive propagation, and protection of breeding sites. This management plan has been implemented only partially, and many of the recommendations remain relevant and applicable not only in Victoria, but throughout the species’ range (P. Du Guesclin pers. comm., D. White pers. comm.). An Action Statement for the species is currently being prepared under Victoria’s Flora and Fauna Guarantee Act (P. Du Guesclin pers. comm.).

Non-governmental Organizations

A citizens’ organization, Friends of the Brolga, was established in 1991. At present it has more than 500 members, mainly landowners in Western Victoria. The group’s efforts have resulted in relocation of utility lines, protection of breeding areas, and the involvement of volunteers in Brolga counts, field days, and education and extension programs (D. White pers. comm.). Since 1991, the group has published a newsletter, Brolga News. The Australian Bird Environment Fund, established by the Bird Observers Club of Australia, may provide support for information-gathering activities carried out by the Friends of the Brolga. In addition, the Victorian Wetland Trust has brought together farmers, wildlife biologists, botanists, planners, and others interested in the conservation of wetlands.

Education and Training

Few education programs have focused specifically on the Brolga. Special educational programs have been developed at the Serendip Wildlife Center. At Kakadu National Park, a “Window on the Wetland” visitor center (designed to symbolize a dancing Brolga) opened in 1994. The center provides visitors with opportunities to learn about the natural history of Kakadu, wildlife ecology, and aboriginal traditions and culture (Beilfuss 1994). A permanent crane and wetland interpretive center is being considered as part of a private/public conservation effort at Cromarty (H. Lavery pers. comm.). The “Land for Wildlife” project, noted above, provides landowners with information on wildlife, including Brolgas, in Victoria and Southern Australia.

Captive Propagation and Reintroduction

As of 1993, an estimated 34 Brolgas were maintained in captivity—19 in Australia and 14 in facilities in other countries (Mirande et al. in press a). This estimate did not include birds at the Serendip Wildlife Center. The captive flock at Serendip was initiated in 1964 using eggs collected from the nests of wild birds as well as two adults brought in from the wild (White 1987). All the birds in the captive flock are derived from the wild population of Brolgas in western Victoria. From 1978-80, eggs were once again collected to supplement the captive population. Artificial insemination was successfully used at Serendip for the first time in 1986. As of 1994, a total of 53 birds were maintained at Serendip: 14 pairs and 25 young (<4 years) birds (P. Du Guesclin pers. comm.).

The Australian Species Management Program has established a target of 55 Brolgas for management, while the GCAR sets a global target of 75 birds (Mirande et al. in press a). In the GCAR, the Brolga was identified as one of the few crane taxa whose captive population may require an influx of wild birds or eggs in order to maintain desirable levels of genetic diversity (C. Mirande pers. comm.). At present, no studbook for the captive population has been developed.

In recent years, the release of captive-bred Brolgas from the Serendip facility has been intermittently recommended and discussed (e.g., Arnol et al. 1984, White 1987, Bransbury 1991). These proposals have dealt exclusively with the potential for release and/or reintroduction of Brolgas in southern Australia. In December 1994, approval was given for a one-time-only release (to take place in 1995 and 1996) of birds currently at Serendip; thereafter, no further breeding of Brolgas for release to the wild is to take place (D. White pers. comm.). Future captive propagation at Serendip will be undertaken only to support maintenance of the captive population and education programs (P. Du Guesclin pers. comm.).

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Priority Conservation Measures

International Agreements and Cooperation
  1. Support international exchanges of conservation biologists, ornithologists, and officials from New Guinea, Australia, and Southeast Asia.
Legal and Cultural Protection
  1. Enact stronger wetland conservation policies and legislation at all levels of government in Australia. In particular, measures to encourage the protection and restoration of prime breeding habitat on private lands in Southern Australia and Victoria are needed.
Initiating a Brolga Conservation Program in New Guinea

In order to gain information and plan effectively for the conservation of the Brolga in New Guinea, the following initial actions should be undertaken:

  1. Conduct surveys to assess the past and present status of the Brolga populations and their habitats, and the degree to which Brolgas may retreat from Australia to New Guinea during periods of drought.

  2. Define the conservation needs of the Brolga populations and their habitats.

  3. Assess the need for stronger legal protection for wetlands in New Guinea.
Protected Areas
  1. Review the extent to which Brolgas use existing protected areas, and the adequacy of current areas in protecting key dry season and breeding habitats.
Habitat Protection and Management
  1. Strengthen watershed-level approaches to wetland conservation and management, especially in the coastal wetlands of northeastern Australia, the Burdekin River basin, and the Murray-Darling river system.

  2. Define critical habitat for Brolgas, both breeding and non-breeding dry season habitat.

  3. Identify critical dry season Brolga congregation areas and provide protection for them and the associated watersheds.

  4. Develop programs (or expand existing programs) to encourage the maintenance, protection, and restoration of Brolga habitat on private lands. These programs may involve a combination of tax benefits, other financial incentives, voluntary management agreements, extension programs, and supporting legislation.
Surveys/Censuses/Monitoring
  1. Establish a systematic, coordinated program to survey and monitor the population in Australia.

  2. Apply habitat predictor models (in conjunction with climate records) to calculate past and present suitable habitat, and use this information to assess trends in the population. (Such techniques are important given the degree of fluctuation in available habitat and Brolga populations in response to Australia’s variable climate patterns)

  3. Establish a program to monitor important nesting areas.

  4. Monitor movements of populations in Australia through an expanded color banding and radio-tracking program.
Research

Research on the Brolga should focus on:

  1. Studies to determine the size and trends in the total population. Various studies (local censuses, breeding success, survival and recruitment rates, flocking behavior, etc.) should be conducted throughout the species range, and this information used to better assess the species’ status.

  2. Studies of breeding habitat and biology throughout the species’ range. In the south, priority should be given to identification of key nesting areas and factors affecting breeding success at different sites to define critical factors and suggest strategies for habitat management restoration. (See Hill (1992) for specific recommendations regarding monitoring of breeding habitat). In the north, priority should be placed on determining the trends in the Brolga populations and their habitats.

  3. Studies of traditional and potential flocking sites used in the course of seasonal movements. These studies are needed to provide a foundation for improved protection and management of these areas. They can be coordinated with broader efforts to understand seasonal movements through expanded banding and radio-tracking studies.

  4. Identification and analysis of isolated and potentially threatened populations (this pertains primarily to southern Australia).

  5. Studies to promote the restoration of degraded wetlands and other habitats used by Brolgas.

  6. Further studies of the interaction and comparative ecology of Brolgas and Australian Sarus Cranes.
Education
  1. Develop public education programs throughout the species’ range, stressing the importance of wetlands for cranes and other waterbirds.

  2. Expand extension and advisory services to encourage the involvement of farmers and other private landowners in crane conservation activities.

  3. Support development of the permanent wetland/Brolga interpretive center at Cromarty.
Captive Propagation and Reintroduction
  1. Implement the recommendations outlined in the Crane GCAR and CAMP (Mirande et al. in press a). These are to:

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