Disease refuge or ecological trap: location-specific performance of amphibian hotspot shelters

Artificial hotspot shelters have been developed as a conservation tool to help frogs thermally escape the amphibian chytrid fungus, a pathogen highly sensitive to elevated temperatures. To evaluate how these structures perform under contrasting climatic conditions, we deployed temperature loggers inside hotspot shelters and beneath wooden board analogue retreats at two Australian field sites: a humid subtropical site in Sydney (NSW) and a cool semi-arid site in Werribee (VIC). Hourly temperatures were recorded throughout winter and used to quantify daily microhabitat thermal regimes relevant to chytrid suppression and amphibian physiology. The dataset presented here consists of daily site-level summaries, including mean temperature, daily maxima and minima, and total hours above biologically important thresholds (20 °C, 25 °C, 30 °C), derived by averaging across all structures at each site. Ambient weather variables from the Australian Bureau of Meteorology are not included due to licensing restrictions, but full station metadata are provided in the article’s supplementary materials.

Methods
iButton loggers recorded hourly temperatures inside each hotspot shelter and beneath wooden board analogue retreats. For each day and each site, temperatures were summarised to daily means, daily maxima and minima, and total hours above biologically relevant thermal thresholds (20 °C, 25 °C, 30 °C). All structure-level values were then averaged to produce a single daily site-level value for each variable.

These site-level summaries were analysed separately for the Sydney and Werribee trials using generalised least squares (GLS) models with an AR(1) correlation structure to account for temporal autocorrelation among days. Models tested how daily microhabitat temperatures responded to ambient maximum temperature and solar exposure.

Note on derived thermal metrics:

Daily values for hours above thermal thresholds (20 °C, 25 °C, 30 °C) and daily mean/max/min temperatures represent derived summaries calculated from the raw hourly iButton logger records. The underlying raw hourly logger data are not included in this repository but can be provided upon reasonable request.