Importance of fire in influencing the occurrence of snakes in an upland region of arid Australia

Experimentally testing animal responses to prescribed fire size and severity

Deserts are often highly biodiverse and provide important habitats for many threatened species. Fire is a dominant disturbance in deserts, and prescribed burning is increasingly being used by conservation managers and Indigenous peoples to mitigate the damaging effects of climate change, invasive plants, and land-use change. The size, severity, and patchiness of fires can affect how animals respond to fire. However, there are almost no studies examining such burn characteristics in desert environments, which precludes the use of such information in conservation planning. Using a before-after control-impact approach with 20 sampling sites, we studied the outcomes of 10 prescribed burns of varying size (5-267 ha), severity, and patchiness to identify which variables best predicted changes in small mammal and reptile species richness and abundance. Three of the 13 species showed a clear response to fire. Captures increased for 2 species (1 mammal, 1 reptile) and decreased for 1 species (a reptile) as the proportional area burned around traps increased. Two other mammal species showed weaker positive responses to fire. Total burn size and burn patchiness were not influential predictors for any species. Changes in capture rates occurred only at sites with the largest and most severe burns. No fire-related changes in capture rates were observed where fires were small and very patchy. Our results suggest that there may be thresholds of fire size or fire severity that trigger responses to fire, which has consequences for management programs underpinned by the patch mosaic burning paradigm. The prescribed burns we studied, which are typical in scale and intensity across many desert regions, facilitated the presence of some taxa and are unlikely to have widespread or persistent negative impacts on small mammal or reptile communities in this ecosystem provided that long unburned habitat harboring threatened species is protected.

Predator responses to fire: A global systematic review and meta-analysis

Knowledge of how disturbances such as fire shape habitat structure and composition, and affect animal interactions, is fundamental to ecology and ecosystem management. Predators also exert strong effects on ecological communities, through top-down regulation of prey and competitors, which can result in trophic cascades. Despite their ubiquity, ecological importance and potential to interact with fire, our general understanding of how predators respond to fire remains poor, hampering ecosystem management. To address this important knowledge gap, we conducted a systematic review and meta-analysis of the effects of fire on terrestrial, vertebrate predators world-wide. We found 160 studies spanning 1978-2018. There were 36 studies with sufficient information for meta-analysis, from which we extracted 96 effect sizes (Hedges' g) for 67 predator species relating to changes in abundance indices, occupancy or resource selection in burned and unburned areas, or before and after fire. Studies spanned geographic locations, taxonomic families and study designs, but most were located in North America and Oceania (59% and 24%, respectively), and largely focussed on felids (24%) and canids (25%). Half (50%) of the studies reported responses to wildfire, and nearly one third concerned prescribed (management) fires. There were no clear, general responses of predators to fire, nor relationships with geographic area, biome or life-history traits (e.g. body mass, hunting strategy and diet). Responses varied considerably between species. Analysis of species for which at least three effect sizes had been reported in the literature revealed that red foxes Vulpes vulpes mostly responded positively to fire (e.g. higher abundance in burned compared to unburned areas) and eastern racers Coluber constrictor negatively, with variances overlapping zero only slightly for both species. Our systematic review and meta-analysis revealed strong variation in predator responses to fire, and major geographic and taxonomic knowledge gaps. Varied responses of predator species to fire likely depend on ecosystem context. Consistent reporting of ongoing monitoring and management experiments is required to improve understanding of the mechanisms driving predator responses to fire, and any broader effects (e.g. trophic interactions). The divergent responses of species in our study suggest that adaptive, context-specific management of predator-fire relationships is required.

A Review Of Major Impact Factors Of Hostilities Influencing Biodiversity In The Eastern Ukraine (Modeled On Selected Animal Species)

We identified major factors (both direct and indirect), caused by the hostilities in Ukrainian ATO zone that adversely influence local biodiversity and environment. Damaged conservational territories (objects of nature conservation fund) were assessed. One of the most severe factors, the fires were studied using data from Terra MODIS remote sensing, resulting in a model of localization and spatial configuration of fires on natural and agricultural territories in ATO zone during June-September 2014. In that period, 2901 ignitions were registered in ATO zone, exceeding the numbers for previous four years. It was determined that 81 % of all of the ignitions happened on natural steppe and forest areas, 19 % in settlements. Th e fires damaged 18 % of forest area, 23 % of the steppe area and 14 % of arable lands of ATO zone. For two snake species of Red book of Ukraine — eastern Elaphe dione and more widespread Hierophis caspius — it was shown that most of the animals and their biotopes in Luhansk and Donetsk Regions of Ukraine are under threat. Far example, 65–82 % of 108 finds of these Colubridae registered in the eastern Ukraine are located in the ATO zone and near to hostilities. GIS models also showed that more than 50 % of biotopes, suitable for these snakes, are in the ATO zone or near it. Based on world-wide experience and our own observations, we safely assume that the events of 2014 in the ATO territory can possibly cause far-reaching adverse consequences for natural landscapes, local flora and fauna, and the massive local disappearance of plant and animal populations.

Extant population of the Critically Endangered central rock-rat Zyzomys pedunculatus located in the Northern territory, Australia

The central rock-rat Zyzomys pedunculatus is categorized as Critically Endangered on the IUCN Red List. Over the last 50 years the species had only been recorded from 14 sites within a 600 km2 area of the West MacDonnell National Park and immediate surroundings in the Northern Territory, Australia. The central rock-rat disappeared from monitoring sites in 2002, coincident with the onset of drought conditions and extensive wildfires. With concern growing for the survival of the species, we sought to locate an extant population. During 2009–2012 we surveyed sites throughout the western sector of the West MacDonnell National Park, including sites where rock-rats had previously been recorded. From a total of 55 sites and 5,000 trap nights we located eight central rock-rats from only five sites (overall detection rate = 0.16 rock-rats per 100 trap nights). All sites were on two mountain-top locations, both of which are over 1,250 m altitude. Evidence of reproductive activity was observed at both locations but the subpopulations were relatively localized and no individuals were captured at any of the sites from which the species was known previous to these surveys. Although the rugged mountains may provide the central rock-rat with some refuge from predation and wildfires, more research is needed to understand better the factors suppressing and constraining the species at the population and landscape scales. Immediate management priorities are prescribed burning to limit the extent and severity of wildfires and trialling a baiting programme with 1080 to target feral cats in the mountains.

Body sizes, activity patterns and habitat relationships of the orange-naped snake (Furina ornata) (Serpentes : Elapidae) in the MacDonnell Ranges, Northern Territory

Orange-naped snakes (Furina ornata) are small elapids that occur in tropical to arid regions throughout northern and central Australia. We report on the first field-based study of this species, investigating body sizes, activity patterns, and habitat use in the semiarid MacDonnell Ranges bioregion of central Australia. Using systematic road-cruising, we encountered 69 live F. ornata along a 77-km sealed road-transect over a 12-month period from August 2009 to July 2010. Based on measures of snout-to-vent length (SVL), we found that female F. ornata (mean SVL = 459 ± 6.3 (s.e.) mm; n = 16) were larger than males (SVL = 372 ± 25.2 (s.e.) mm; n = 44) (t = 4.7358, P < 0.0001), and that both sexes were larger than previously reported from museum specimens. Despite the extreme weather variability experienced in arid Australia, we found that activity patterns were not significantly related to temperature, rainfall or humidity, and F. ornata was active in all but the single coldest month of the year. The habitat-use analysis found that F. ornata was more likely to be recorded in areas with greater cover of hummock grass (Triodia spp.) and less cover of rocky outcrops or boulders. Hummock grasslands in arid Australia have an abundant and diverse skink fauna, which may attract F. ornata, whose diet consists primarily of diurnal skinks.