National recovery plan for Stream Frogs of South-east Queensland 2001-2005

Prepared by Harry Hines
Queensland Parks and Wildlife Service
and the South-east Queensland Threatened Frogs Recovery Team, 2002

Introduction

This recovery plan has been developed from the draft recovery plan for the southern gastric-brooding frog and southern dayfrog (Martin et al. 1997), a draft national recovery plan for barred-frogs and the cascade tree frog (QPWS 2000), and the draft recovery plan for the Kroombit tinkerfrog (Borsboom et al. 1999). The earlier plans have been partially implemented. This recovery plan has been prepared for adoption under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999. It provides an overview of the decline of seven stream-dwelling frog species of south-eastern Queensland and actions needed to recover these species.

Location and species

This plan includes seven species of threatened stream frogs from south-east Queensland (Table 1).

Table 1. Current status of species considered in this recovery plan.
Common name
Scientific name
EPBC
Act
19991
Action
Plan
19972
Qld
NC(W)
Reg 19943
IUCN4
Fleay’s barred-frog Mixophyes fleayi
EN
EN
EN
EN [B2ab(iii)]
Giant barred-frog Mixophyes iteratus
EN
EN
EN
EN [B2ab(iii)]
Southern gastric-brooding frog Rheobatrachus silus
EX
EN
EN
EX
Southern dayfrog Taudactylus diurnus
EX
EN
EN
EX
Kroombit tinkerfrog Taudactylus pleione
VU
VU
VU
CR [B1ab(iii,v)+2ab(iii,v)]
Cascade tree frog Litoria pearsoniana
NL
IK
EN
LC
New England tree frog Litoria subglandulosa5
NL
IK
VU
NT

Codes used (as defined in the relevant legislation/document); EX = presumed extinct, CR = critically endangered, EN = endangered, VU = vulnerable, IK = insufficiently known species that may be of concern, NT = near threatened, LC = least concern, NL = not listed as threatened.

Source: (as at April 2001)

1 Commonwealth Environment Protection and Biodiversity Conservation Act 1999.
2 Tyler 1997.
3 Queensland Nature Conservation (Wildlife) Regulation 1994.
4 IUCN Red List Category (2001), as determined at the IUCN workshop held in Hobart 2001. Criteria are shown in square brackets.
5 Litoria subglandulosa sensu lato - see appendix for details.

In Queensland the distribution of these frogs lies within the region extending south along the foothills and ranges of the Great Divide from about Gladstone to the New South Wales border. The area is fully encompassed by the Southeast Queensland and New England Tableland Bioregions (Stanton and Morgan 1977). Three of the species are restricted to the former. The other four species also occur farther south in New South Wales.

A species profile for each frog, which includes a description of distribution, habitat, biology and threats, is provided as an Appendix. This recovery plan is concerned only with actions necessary for the recovery of populations of the seven threatened frogs in south-east Queensland. The New South Wales National Parks and Wildlife Service are preparing recovery plans for New South Wales populations.

Declines, disappearances and possible causes

Declines of frogs from rainforest streams in south-east Queensland were first noticed in the late 1970s. By the early 1980s, the southern dayfrog and southern gastric-brooding frog had disappeared and at least three other species had declined - Fleay's barred-frog, giant barred-frog and cascade tree frog.

Similar declines and disappearances subsequently occurred along streams in other rainforest areas. On the Eungella Plateau in mid-east Queensland, the northern gastric-brooding frog Rheobatrachus vitellinus was last seen in the wild in 1985, and other species declined at the same time. During the early 1990s, seven frog species endemic to the Wet Tropics declined or disappeared - three remain missing.

Since then, declines of two other stream frogs from south-east Queensland have been detected. The New England tree frog was only known in Queensland from two sites in Girraween National Park. It has disappeared from one of those sites, but has been located at a few new sites. The Kroombit tinkerfrog was discovered in 1983 and occurs in a dozen small pockets of rainforest at Kroombit Tops. In the late 1990s, the only intensively monitored population declined dramatically. Its population is now estimated to consist of hundreds of individuals.

Catastrophic declines have also been documented from overseas rainforests, for example in Costa Rica and Panama. Campbell (1999) has reviewed the declines and disappearances of Australian frogs. The causes of the declines and disappearances are unknown, although several hypotheses have been proposed. It is not known whether the declines were caused by the same factor(s) in different species and in different regions. However, the patterns of decline are similar. The declines were rapid; the species that suffered were dependent upon streams in wet forests (principally rainforest); and species that bred away from streams were not affected.

The identification of the major threatening processes affecting stream frogs in south-east Queensland is an objective of the recovery plan. Recent studies of amphibian disease have identified a chytrid fungus as a cause of frog mortality and as the cause of death of frogs collected during declines (Berger et al. 1998, Berger et al. 1999). The investigation of the role played by chytrid fungus during frog declines is now a major focus of the amphibian disease project. This recovery program and others in Australia and overseas have strong links with the frog disease project. The chytrid fungus has been widely recorded in south-east Queensland from a range of frog species.

Other theories of causal agents have been postulated, for example increased UV-B radiation, chemical pollutants, climate change, or some synergistic or cumulative effect of multiple agents. However, at present there are no well developed hypotheses relating these possible causes to frog declines in south-east Queensland. If necessary, the recovery plan will be modified to include investigations of other threatening processes.

Although considerable work is required investigate and manage the regional declines of stream dwelling frogs, local threats to their habitat and remaining populations also need to be addressed. These threats arise from clearing, introduced fish, mammals and weeds, forestry activities, agriculture, mining, tourism, domestic stock and hydrological changes (Parris and Norton 1997, Gillespie and Hines 1999, Gillespie and Hero 1999; Hines et al.1999). Protection of the habitat and remnant populations of threatened stream frogs is another objective of this plan.

Habitat critical to survival

This plan does not cover the full range of four species, Fleay's barred-frog Mixophyes fleayi, Giant barred-frog Mixophyes iterates, Cascade tree frog Litoria pearsoniana and New England tree frog Litoria subglandulosa. These species also occurs in NSW. The habitat critical to the survival of the species described in this plan is critical habitat occurring within the region covered by this plan. It should be noted that additional critical habitat for this species may occur in other parts of its range.

Habitat critical to the survival of the species considered in the plan is described in Table 2. For most species, critical habitat has been defined in terms of stream environments. All but two species are obligate stream breeders, that is, frogs with tadpoles that develop in streams. The southern gastric-brooding frog is almost entirely aquatic and is never seen more than a few metres from streams. Its tadpoles develop within the stomach of the female. The breeding biology of the Kroombit tinkerfrog is not known, but calling males are only found in rainforest and are almost always associated with watercourses or seepage areas.

For the purpose of describing critical habitat, a stream is defined as a 40m corridor centred on the middle of the stream bed. While this definition may help protect the stream and its immediate surrounds, it is likely to be inadequate for protecting water quality, hydrological processes and non-breeding habitat of the frogs. Quantitative information on non-breeding habitat usage is scant. Some species have never been recorded far from streams but others, such as females of Fleay's barred-frog, have been observed many hundreds of metres from breeding sites. Therefore the definition of critical habitat may be broadened in future revisions of the plan when there is better knowledge of non-breeding habitat requirements.

Table 2. Critical habitat for frogs stream frogs of south-east Queensland.
Common name Habitat critical for breeding
Fleay’s barred-frog Permanent and semi-permanent freshwater streams, between 100-1000m in altitude, in rainforest and other forest communities of the McPherson, Main and Conondale Ranges, Mount Tamborine, and the Mistake and Bunya Mountains.
Giant barred-frog Permanent freshwater streams from 0-700m in altitude, in rainforest and other forest communities of the McPherson, Main, D’Aguilar, Blackall and Conondale Ranges and the Bunya Mountains. Includes narrow riparian rainforest remnants along the following streams and their major tributaries: Maroochy River, Mary River, Stanley River downstream to Kilcoy, Caboolture River, Burpengary Creek, Coomera River and Nerang River.
Southern gastric-brooding frog and southern dayfrog Permanent to ephemeral freshwater streams over 300m in altitude, in rainforest and wet sclerophyll forest communities of the Blackall, Conondale and D’Aguilar Ranges.
Kroombit tinkerfrog and Kroombit Tops population of cascade tree frog Rainforest patches over 500m in altitude at Kroombit Tops (Kroombit Tops National Park and Kroombit Tops Forest Reserve).
Cascade tree frog Permanent and semi-permanent freshwater streams, between 100-1000m in altitude, in rainforest and other forest communities of the McPherson, Main, Blackall and Conondale Ranges, Mount Tamborine, the Mistake Mountains and Girraween National Park.
New England tree frog Permanent to ephemeral freshwater streams over 700m in altitude in Girraween National Park.

Existing conservation measures

The majority of known sites with threatened stream frogs occur in conservation reserves or state forest. Recovery actions, outlined in earlier recovery plans, have been implemented since 1998. Recovery tasks recently completed include:

  • Surveys and monitoring across the geographical and environmental range of each species.
  • Development and implementation of management prescriptions to protect threatened frog habitat.
  • Investigation of the ecology of extant species.
  • Increased awareness of the declining frogs problem through the provision of interpretive brochures and displays, public presentations and scientific publications.
  • Increased community involvement in all aspects of the recovery process.
  • Investigation of ill and dead frogs collected during monitoring or submitted by the public. Identification of the chytrid fungus as a possible threatening process.
  • Development of captive husbandry techniques for Fleay's barred-frog at Lone Pine Koala Sanctuary.
  • Collaborative projects with land care groups and local and state government agencies to more effectively manage the habitat of threatened stream frogs on private land.
  • Collaborative projects with universities to carry out research into the ecology of, and threats to, the frogs.

Stakeholders affected by the plan

The seven frogs included in the plan occur mainly on lands managed under the Nature Conservation Act 1992 or the Forestry Act 1959. Some habitat of the threatened frogs occurs on private land. The most poorly protected species is the giant barred-frog, as the habitat of its most significant populations, in the lower catchments of the Stanley and Mary Rivers, occurs almost entirely on private lands. Local community groups are facilitating recovery efforts in these catchments. Potential habitat for some of the species occurs on Commonwealth Land and extensive habitat occurs in World Heritage listed areas of south-east Queensland.

Timber harvesting has now ceased in most catchments where these frogs occur. Logging within state-managed forests must be compliant with The Code of Practice - Native Forest Timber Production. Specific protective measures for threatened species are provided in The Code through Species Management Profiles. Profiles have been developed for all frogs in the plan that are known to occur in timber production forests and will be reviewed periodically.

Potential habitat for some of the species in this plan occurs on Commonwealth land in the Army training area at Canungra. The recovery team has conducted some surveys in this area but more effort is required to determine the presence of threatened frogs. The Army employs an environmental officer who has participated in the survey. The officer also undertakes rehabilitation of riparian rainforest communities in the training area.

An extensive area of potential and occupied habitat of three species occurs in the Central Eastern Rainforest Reserves (CERRA) World Heritage Area. The habitat includes sections of Springbrook, Lamington, Mount Barney and Main Range National Parks and Forest Reserves. The three species of frogs are recognised as making an important contribution to the World Heritage values of the Area.

The development of the plan has included consultation with and participation by interested parties. The recovery team also has established mechanisms for consultation of, and participation by interested parties. The recovery process outlined in this plan is unlikely to have any significant adverse social or economic impact.

Social and economic impacts. The implementation of this recovery plan is unlikely to cause significant adverse social and economic impacts.

International Obligations. Although the southern gastric-brooding frog Rheobatrachus silus is listed in Appendix II of CITES, this recovery plan does not affect Australia's obligations under international agreements. As the other species are not listed under any international agreement, the implementation of Australia's international environmental responsibilities in regard to these species is not affected by this plan.

Role and interests of indigenous people. Indigenous communities involved in the regions affected by this plan have not yet been identified. Implementation of recovery actions under this plan will include consideration of the role and interests of indigenous communities in the region.

Other plans affected

The recovery plan will be influenced by the Queensland National Parks Master Plan. The Master Plan stresses that conservation of natural and cultural resources is the highest priority in park management, and sets guiding principles for the maintenance of natural integrity. Through the Master Plan, the recovery plan will be linked to a state-wide planning process incorporating strategic plans and policies for threatened flora and fauna.

Management plans or strategies are currently being prepared for national parks and forest reserves in south-east Queensland. These documents provide the framework for implementing the recovery actions from this plan in conservation reserves.

There are various mechanisms for the management and protection of World Heritage properties and values in CERRA. An overview of these is provided by Commonwealth of Australia (2000). Part of this strategy is the park management planning processes discussed above. World Heritage is considered a matter of national environmental significance for the purposes of the Commonwealth's Environment Protection and Biodiversity Act 1999. This legislation applies throughout CERRA to ensure the protection of World Heritage values (Commonwealth of Australia 2000).

Weirs and dams used as major surface water extraction sites occur within the habitat of the threatened frogs considered in this recovery plan. Many other streams could potentially be used for water extraction, or could be subject to regulation. The potential impact of existing or proposed water extraction on the frogs has not been examined. Queensland's statute law relating to the allocation and management of water is primarily contained in the Water Act 2000, administered by the Department of Natural Resources and Mines.

A new water allocation and management system is being established which provides a framework within which State-owned, semi-government and private water development can operate to provide for ecologically sustainable development. This new system of Water Resource Plans will progressively replace the existing licencing system. In south-east Queensland, Water Resource Plans are currently being prepared or implemented for the following catchments; Logan, Albert, Burnett, Boyne, Calliope, Mary, Burrum, Brisbane, Pine and Caboolture Rivers and the smaller catchments of the Sunshine and Gold Coasts.

Recovery team, reporting and review

The South-east Queensland Threatened Frogs Recovery Team is responsible for preparing, implementing and evaluating the recovery plan. Currently the recovery team includes representatives from QPWS, the Threatened Species Network, Lone Pine Koala Sanctuary and universities. Membership is reviewed periodically.

Progress in implementing the actions of the plan will be reviewed each year. Reports on implementation of the actions will be provided to the recovery team to facilitate the process. Where necessary, actions identified in the plan will be modified by the recovery team to incorporate new information.

The recovery plan will be fully reviewed at the end of the third year by the South-east Queensland Threatened Frogs Recovery Team and two independent reviewers.

Other biodiversity benefits

  • Increased information on the ecology, habitat requirements, diseases and other threatening processes that have influenced the distribution and abundance of these frogs will assist in understanding the declines of amphibians in other parts of Australia and overseas.
  • Amphibians are exposed to both terrestrial and aquatic environments during their life cycles and, having highly permeable skins, are highly susceptible to environmental changes. Consequently they are likely to be important indicators of environmental health.
  • The frogs covered by the plan are important components of the forest stream trophic system, and fluctuations in their numbers may considerably influence the abundance and distribution of their food sources and predators. Understanding the causes of declines in these frog populations may contribute to improved catchment management in eastern Australia.
  • Protection and management of habitat will benefit other rare or threatened flora and fauna (for example the threatened Richmond birdwing butterfly).
  • Greater community awareness of the decline or disappearance of threatened frogs will raise the profile of all threatened species. This will in turn provide more opportunities for the conservation of threatened species and consequently, increased biodiversity benefits.

Strategy for recovery

Recovery of the threatened frogs considered in this plan is dependent on identifying the major threats and developing and implementing measures to ameliorate or eliminate their impact. Testing the hypothesis that disease is a major cause of the rapid declines of montane stream-dwelling frogs in eastern Australia is a significant aspect of the plan. To support this research, it is critical that ongoing monitoring of populations should continue. Other components of this plan will deal with the management of populations and their habitat in an effort to reduce impacts from other processes until the major threats are identified and reduced.

The number of species and the wide geographical area covered in the recovery plan, and the range of organisations involved, necessitates the appointment of a recovery co-ordinator to ensure that recovery actions are carried out effectively and efficiently.

Another critical part of the recovery process is the education and involvement of relevant land managers and the general public. Without government and community support, recovery of these species will not be possible.