*****NOTE: THIS IS A DRAFT STRATEGY***** Chytridiomycosis is a fatal disease of amphibians and is caused by the chytrid fungus Batrachochytrium dendrobatidis. Chytridiomycosis is a global epidemic and is potentially fatal to all native species of amphibian. Stream-associated frog species and populations at high altitude (>400m) are more likely to be susceptible to the disease. The infection requires water or direct contact between frogs to spread, and its virulence appears sensitive to temperature. Fifty species of Australian frogs have been found infected with the chytrid fungus.
Biodiversity values impacted
Chytridiomycosis has the potential to impact all amphibian species occurring in NSW, including up to 26 threatened frogs. Impacted populations have generally been reported in and to the east of the Great Dividing Range, across all latitudes. The severity of impact on population dynamics varies between species and locations, but has the potential to cause local extinction.
To prevent the spread of chytrid between amphibian populations and minimise the impacts of infection on susceptible populations across NSW, and to improve understanding of the disease’s dynamics and how they interact with amphibian physiology, genetics and population dynamics, with a view to enhancing immunity.
The SoS strategy aims to secure the species in the wild for 100 years and maintain its conservation status under the BC Act
The SoS strategy aims to secure the species in the wild in NSW for 100 years, engage local communities in its conservation, and encourage the NSW community to identify with it as a flagship for threatened species conservation.
This action statement aims to address key knowledge gaps for this species, which once resolved, can inform effective management of this species.
This action statement aims to ensure the security of this species in the long-term.
This action statement aims to ensure that the species is secure in the wild in NSW and that its NSW geographic range is extended or maintained.
This action statement aims to secure critical populations of this species in NSW in the long-term.
This action statement aims to secure this population in the long-term.
This action statement aims to maximise the extent of occurrence and condition of the ecological community across NSW.
Priority actions for this KTP
|Develop and improve the application of assisted reproductive technologies to improve outcomes from captive breeding programs.||State
|Test reintroduction of individuals from potentially resistant populations into sites where the species is known to have occurred previously, or susceptible individuals into sites where chytrid and/or host species (e.g. common eastern froglet) are absent. Monitor reintroduced populations closely with respect to chytrid infection and demographics to better understand the dynamics of both.||Site
|Using molecular techniques, investigate genetic variation in immune and susceptible species/populations to identify genes that code for disease resistance. Explore methods for increasing resistance genes in populations via selective breeding, gene transfer or genomic selection.||State
|Implement adaptive management of particular populations to identify environmental drivers of chytrid infection and test methods for reducing risk and maintaining population viability. This includes improving understanding of how chytrid interacts with other threats and environmental processes (e.g. habitat disturbance, climate change, and invasive species such as trout and gambusia) to inform management that will increase population resilience. Also, aim to improve understanding of the reasons why particular amphibian populations are able to persist with fewer demographic impacts at particular locations, in order to apply those learnings to susceptible populations.||Site
|Enhance and support the ability of existing biosecurity and surveillance measures to detect new strains of chytrid or other pathogens entering Australia (NSW in particular). Develop appropriate communication protocols and a management plan to be triggered in response to the detection of new amphibian pathogens or disease outbreaks in NSW.||State
|No critical actions have been identified under a containment response as chytrid is common in NSW and cannot be contained to a specific location.||State
|Identify key entry points to sites where important susceptible amphibian populations occur and establish disinfecting/wash stations for bushwalkers, researchers and other people entering these sites.||Site
|Produce guidelines for developers to mitigate spread of chytrid during and following construction activities. The guidelines should include reference to, for example, hygiene protocols for contractors on site, as well as guidance on sensitive design (e.g. avoiding creating standing ponds which may attract known chytrid host species).||State
|Develop and implement an education campaign targeting frog study groups, photographers and naturalists, to promote the use of proper hygiene protocols in the field when handling/photographing frogs, as well as to raise awareness about the potential for damaging important habitat. The campaign should target groups such as the Frog and Tadpole Society (FATS), Frogography, field naturalist groups, and universities (particularly coordinators of undergraduate field trips). Develop supporting resources such as hygiene protocols that are made available and are useful for all relevant stakeholders.||State
|Establish a gene bank to preserve genetic material (e.g. sperm, eggs, tissue) from multiple cell lines for amphibian species at high risk of extinction due to chytrid. Selection and prioritisation of populations to sample should be informed by relevant phylogenies and population genetic data in order to capture appropriate genetic variation. Develop an appropriate governance framework including physical storage at a national or state institution (e.g. museum) and clear guidance on using material if/when required.||State
Distribution of the KTP in NSW
Your search returned one or more sites that are restricted due to the sensitive nature of either the species or the site. Individuals involved in management on these sites can access detailed information via the database.
Biodiversity asset protection
The priorities for management of amphibian populations impacted by chytrid are focused on increasing resilience via the abatement of other threatening processes, preventing the spread of chytrid throughout the landscape, maintaining chytrid-free refuges and monitoring the health and demographics of populations. The table below outlines the threatened species strategies that are implementing actions to manage the threat of chytrid at a priority SoS site. The table is not a comprehensive list of all species or sites impacted by the threat in NSW.
Priorities for investment in particular projects under SoS will be determined based on alignment with the
critical actions outlined above, as well as their benefit (in terms of meeting SoS objectives) relative to
implementation cost, as per the SoS KTP Framework.
Monitoring and evaluation
No monitoring and evaluation information available.
Interaction with other KTPs
|Anthropogenic Climate Change||It is highly likely that climate change will increase future chytrid impacts in some areas, whilst reducing them elsewhere. Protection of climate refuges, where environmental conditions prevent disease outbreaks can therefore assist some species. Functional trait models have the potential to inform where microhabitat manipulations might be adopted to reduce chytrid transmission under future climate scenarios.
|Invasion and establishment of the Cane Toad (Bufo marinus)||The effect of chytrid on toads and the role of toads in amplifying or spreading chytrid is uncertain but is probably not important in most areas. This is because 1) adult toads are rarely infected in the wild and 2) although in the lab tadpoles and metamorphs can be infected and metamorphs die with heavy infections, natural toad breeding sites are generally too warm for the fungus. However, in the colder parts of the toad range there are potential impacts.
How will this species be managed?
Key management sites for this threatened species are being identified by the NSW Government
and other program partners, where feasible, cost-effective and beneficial management actions can be undertaken.
Currently, no management sites have been identified for this threatened species.
Identify whether individuals from populations differing in degree of population recovery exhibit corresponding variation in their degree of susceptibility/resistance to infection in a controlled laboratory environment.
Identify the degree of variation between populations in terms of underlying natural genetic drift.
Identify specific immune mechanisms occurring throughout active infection, comparing this with both control (unexposed frogs) and between source populations for any major observed differences.
Characterise key genes involved in the immune response and compare allelic diversity between populations for these key immune genes.
Identify whether any allelic diversity identified is associated with directional (positive) selection that could be consistent with the evolution of resistance to chytridiomycosis.