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Prescribed fires are widely used for oak (Quercus) regeneration in hardwood forests, but the reported effects on terrestrial salamanders are variable, with some authors describing little to no effect of prescribed fire on salamanders and others reporting negative results. Factors such as variable fire intensity, sampling methodology, and imperfect salamander detection, which vary by study, may influence the effects of prescribed fires on salamanders. We examined the response of red-backed (Plethodon cinereus) and zig-zag (Plethodon dorsalis) salamanders to prescribed fire in forests of the Midwest U.S., accounting for changes in salamander behavior and detection by accounting for capture probability, and considering the influence of local fire intensity. We also explored the effects of fire on environmental variables (leaf litter depth, soil moisture, soil temperature, and soil pH) to identify possible mechanisms driving fire's influence on salamanders. From spring 2019 through fall 2022, a total of 4922 salamander captures were recorded, representing 1939 individually marked salamanders at six coverboard grids in southern Indiana. Occurrence of fire affected survival and temporary emigration of salamanders, likely indicating that salamanders retreated underground, on two of the four grids. Fire occurrence and intensity did not significantly affect environmental variables except for leaf litter depth, which was negatively affected. However, soil moisture had a stronger influence on salamander capture probability than leaf litter. Overall, effects of prescribed fires on salamander populations in this study were inconsistent. In contrast, environmental factors had strong impacts on salamanders, but themselves exhibited either no relationship or a short-term relationship to prescribed fire variables. Notably, large salamander populations may be better able to tolerate prescribed fires. Such populations will be important to support during prescribed fire management to protect the species, especially as the effects of repeated prescribed fires and compounding effects are unknown. Understanding the interplay between forest management practices and wildlife habitat features such as soil moisture and leaf litter will be critical to identifying best practices for supporting wildlife populations reliant on such features during prescribed fires. • Of three prescribed fires in southern Indiana, only two affected salamander populations. • Prescribed fire effects on salamanders were variable, overshadowed by environmental factors. • Large salamander populations may better tolerate prescribed fires. • Supporting salamander populations during prescribed fires is important for forest management. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Prescribed burning is a key risk reduction tool in southern Australia. • Effective risk planning requires predictable prescribed burn outcomes. • Over a 6-year period, 29.6% of planned burns were not completed. • Of completed burns, a median of 15.5% of area remained unburnt. • Burn coverage could be predicted from burn size, fuel type, seasonality and aridity. Abstract Prescribed burning is a widely used strategy in forested landscapes to reduce the risk from wildfires to human lives and valued assets. The ability for managers to undertake prescribed burns is contingent on fuel, weather and operational constraints. In practice, not all areas nominated to be burnt get completed, and within burns that occur, not all the area is burnt. There has been limited research into rates of successful implementation of prescribed burns for fuel management and the degree to which the outcomes of prescribed burning are predictable. To better understand this, we undertook a quantitative analysis of prescribed burn outcomes in the State of Victoria, Australia between July 2009 and July 2015, investigating the likelihood of burns being completed and the time between nomination and completion. For those completed, we used Generalized Additive Models to investigate patterns of burn coverage, both for individual points within burns and aggregated to the burn level. We found a large proportion (29.6%) of scheduled prescribed burns were never burnt, and the time between nomination and completion was highly variable. The size of the nominated burn area was found to influence both the likelihood of completion and the likelihood of burns being postponed. Of burns that were completed, the proportion of area burnt was highly variable (mean 74%, median 84%). Patterns of burnt area were predictable: our point level model could predict the likelihood of any point within a burn being burnt with 66% accuracy from fuel type, aridity and temperature seasonality. The model was more confident in predicting what would remain unburnt than what would burn. Our burn level model explained 55% of variation in the proportion burnt from area weighted fuel type, average aridity, temperature seasonality and the size of the nominated burn area. An ability to foresee the outcomes of prescribed burn programs is important for managers in designing effective risk reduction programs. [ABSTRACT FROM AUTHOR]

Highlights • Box turtle survival decreased with increasing fire extent and frequency in longleaf pine forests. • Disease resulted in more deaths in box turtles than direct interactions with fire. • Fire did not affect turtle growth rates or body condition. • Mortality peaked in winter and spring in both fire-maintained and unburned forests. • Females had higher mortality rates than males in both fire-maintained and unburned forests. Abstract Prescribed fire is commonly used as a tool to meet a range of forest management goals. Owing to their limited movement abilities, terrestrial turtles are likely to be at high risk of injury and mortality, and to experience other fitness consequences with population-level implications from fire. Using radiotelemetry, we studied the responses of Eastern Box Turtles, Terrapene carolina carolina , to prescribed fire management in a sandhills Longleaf Pine forest system over a five-year period and compared our results to a nearby population in an unburned coastal plain location. Individual variation in turtle survival was strongly dependent on how frequently and extensively the areas were burned, with annual survival rates of 94.5% in unburned areas decreasing to 45.9% in the most extensively burned areas. Turtles at the fire-maintained sandhills site had annual survival rates 4.9% less than at the unburned coastal plain site, and females had annual survival rates 6.8% less than males. Survival varied seasonally, with greatest mortality rates in winter and spring, especially among females. Growth rates and body condition did not differ between sites, nor did they vary according to fire extent and frequency at the fire-maintained site. Although mortality was greater and spatially variable at the fire- maintained site, annual survival rates across the site (86–90% for females and males, respectively) were comparable to other stable populations of T. carolina. The lesser than expected mortality rate at the fire-maintained site was likely the result of turtles' strong selection of mesic hardwood forests near bottomlands and streams – habitats that may serve as refugia from fire. In areas where T. carolina conservation is a priority, land managers should integrate maintenance of fire refuge habitats into burn planning to minimize unintended negative impacts to this imperiled species. [ABSTRACT FROM AUTHOR]

Prescribed fire conducted in fire-prone areas is a cost-effective choice for forest management, but it also affects many of the physicochemical and bio-geological properties of the forest soil, in a similar manner to wild fires. The aim of this study is to investigate the nature of the mercury mobilization after a prescribed fire and the subsequent temporal changes in concentration. A prescribed fire was conducted in a legacy mine site in Central Victoria, Australia, in late August 2015 and soil sample collection and analyses were carried out two days before and two days after the fire, followed by collection at the end of each season and after an intense rainfall event in September 2016. Results revealed the occurrence of mercury volatilization (8.3–97%) during the fire, and the mercury concentration displayed a significant difference (p < 0.05) before and immediately after the fire. Integrated assessment with number of pollution indices has shown that the study site is extremely contaminated with mercury during all the sampling events, and this poses a serious ecological risk due to the health impacts of mercury on human and ecosystems. In times of climate fluctuation with concomitant increase in forest fire (including prescribed fire), and subsequent precipitation and runoff, the potential for an increased amount of mercury being mobilized is of heighted significance. Therefore, it is recommended that prescribed fire should be cautiously considered as a forest management strategy in any mercury affected landscapes. [ABSTRACT FROM AUTHOR]

• Turtles selected habitats that provided refuge from winter prescribed fires. • Turtles buried deep enough to avoid lethal temperatures during winter fires. • Spring emergence varied over a 58-day period, but was repeatable within individuals. • Turtles maintained less spatial fidelity to refuges in burned areas. • No fire-related injury or mortality occurred during winter dormancy. • Burning during winter dormancy may minimize threats to turtle populations. Prescribed fire is an essential management practice in pyrogenic ecosystems, but fire can also be a significant disturbance and source of mortality for both target and non-target species. Seasonal periods of animal inactivity may provide opportunities to design burn plans that minimize negative impacts to species of conservation concern, but few studies have rigorously examined this possibility. Using radiotelemetry, we studied overwintering behavior and interactions with fire in a forest-dwelling terrestrial turtle, the Eastern Box Turtle (Terrapene carolina carolina), over an eight-year period at two sites that use prescribed fire in forest management. Turtles at both sites selected predominantly hardwood forests and mesic habitats and avoided upland pine forests. Turtles buried deepest (2.9 – 3.2 cm) below the soil-litter interface in late February and then moved gradually shallower until emergence in early April. Emergence timing varied over a 58-day period, but was consistent within individuals from year to year. Turtles also maintained fidelity to refuge locations, but those overwintering in burned areas selected sites over twice as far from refuges used in previous years compared to those in unburned areas. The areas and habitats selected by turtles during winter served as refugia from fire, and those whose refuges did burn remained buffered from lethal temperatures even at shallow burial depths. The only fire-related injury or mortality occurred during seasons of surface activity. Timing burning and other forest management practices during periods of winter dormancy may thus minimize threats to turtle populations, but modifications to prescribed fire regimes must also be balanced with other management objectives. [ABSTRACT FROM AUTHOR]