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Summary1. Altered global climates in the 21st century pose serious threats for biological systems and practical actions are needed to mount a response for species at risk. 2. We identify management actions from across the world and from diverse disciplines that are applicable to minimizing loss of amphibian biodiversity under climate change. Actions were grouped under three thematic areas of intervention: (i) installation of microclimate and microhabitat refuges; (ii) enhancement and restoration of breeding sites; and (iii) manipulation of hydroperiod or water levels at breeding sites. 3. Synthesis and applications. There are currently few meaningful management actions that will tangibly impact the pervasive threat of climate change on amphibians. A host of potentially useful but poorly tested actions could be incorporated into local or regional management plans, programmes and activities for amphibians. Examples include: installation of irrigation sprayers to manipulate water potentials at breeding sites; retention or supplementation of natural and artificial shelters (e.g. logs, cover boards) to reduce desiccation and thermal stress; manipulation of canopy cover over ponds to reduce water temperature; and, creation of hydrologoically diverse wetland habitats capable of supporting larval development under variable rainfall

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The susceptibility of Archey's frog Leiopelma archeyi to Batrachochytrium dendrobatidis (Bd) is unknown, although one large population is thought to have declined sharply due to chytridiomycosis. As primary infection experiments were not permitted in this endangered New Zealand species, 6 wild-caught L. archeyi that naturally cleared infections with Bd while in captivity were exposed again to Bd to assess their immunity. These frogs were from an infected population at Whareorino, which has no known declines. All 6 L. archeyi became reinfected at low intensities, but rapidly self cured, most by 2 wk. Six Litoria ewingii were used as positive controls and developed heavier infections and clinical signs by 3 wk, demonstrating that the zoospore inoculum was virulent. Six negative controls of each species remained uninfected and healthy. Our results show that L. archeyi that have self cured have resistance to chytridiomycosis when exposed. The pattern is consistent with innate or acquired immunity to Bd, and immunological studies are needed to confirm this. KEY WORDS: Leiopelma archeyi · Litoria ewingii · Batrachochytrium dendrobatidis · Chytridiomycosis Resale or republication not permitted without written consent of the publisherContribution to DAO Special 4 'Chytridiomycosis: an emerging disease'

The spread of chytridiomycosis, an emerging infectious disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is one of many threats facing amphibians worldwide. Ascertaining the severity of this threat to particular amphibian species is necessary if managers are to prioritize conservation actions. In New Zealand, Bd has been detected on both threatened endemic (Leiopelma spp.) and widespread introduced (Litoria spp.) anuran species, but Le. archeyi, one of four native species, has demonstrated low susceptibility to chytridiomycosis in captivity. To determine potential impacts of Bd on New Zealand's native anuran fauna, we assessed the susceptibility of two native species, Le. pakeka and Le. hochstetteri, to chytridiomycosis. We exposed Bd-naïve individuals to a virulent New Zealand isolate of Bd, and monitored infection status with quantitative real-time polymerase chain reaction. Both species demonstrated low susceptibility and all individuals cleared Bd infection (Le. hochstetteri by week 10, Le. pakeka by week 15). Furthermore, no frogs demonstrated clinical signs of chytridiomycosis. Since Le. archeyi has similarly demonstrated low susceptibility, this appears to be a genus-wide trend, which warrants further study of the mechanism of this response. These findings, in agreement with results from field surveys and analyses of skin peptide defenses, suggest that Bd poses a low risk to leiopelmatids. An investigative study of potential susceptibility to Bd, such as this one, can better equip managers to target imminent threats and focus conservation plans for at-risk amphibian fauna.