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Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum., (© 2020 The Authors. Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

In response to foraging for foods that fluctuate in availability, generalists often exhibit the ability to switch between different food sources. Many of the Carnivora on an omnivorous-frugivorous diet display temporal dietary switching and specialism, but the mechanisms underlying this are incompletely understood. Here we studied the diet of the opportunistically frugivorous yellow-throated marten (Martes flavigula) with regard to food-resource exploitation in a subtropical forest of central China. Diet was determined through scat analyses combined with surveys to estimate local food abundance. Peak fruit consumption and the lowest utilization of small mammals occurred when fruit abundance reached its temporal maximum in the environment in synchrony with a concomitant peak in small mammal abundance. When both fruits and small mammals were least abundant in the environment, the marten's diet shifted to the maximum utilization of small mammals with no fruit consumption. This dietary switching could not be explained by the fluctuation in the abundance of principal prey in the environment, that is, small mammals, but by the ease of procurement of fruit at peak fruiting season. The marten's diet thus does not simply reflect primary resource abundance but is a function of the relative abundance and inferred availability of alternative food types. This case study of the yellow-throated marten provides insight into foraging strategies that depend on the relative, temporal availability of food types, a phenomenon observed for other generalist omnivores (including several Carnivora). [ABSTRACT FROM AUTHOR]

Patterns of space use can provide valuable insights into patterns of activity and social structure of poorly known mammal species. From April 2005 to November 2006 we radiotracked a low-density population of ferret badgers (Melogale moschata) in central China. Fourteen males and 8 females were caught. Nine of these individuals (6 males and 3 females) were followed; mean (± SD) 100% minimum convex polygon (MCP100) home range was 128.3 ± 131.9 ha, with no difference between sexes. For MCP100, neither nightly movement distances nor daily activity patterns revealed significant variation due to sex or season. Core areas (50% minimum convex polygon [MCP50]) were typically located centrally within overall home ranges. Two distinct groups of animals were evident in the radiotracked subpopulation, one consisting of 7 adults and the other composed of at least the 2 remaining collared badgers with field signs of additional badgers from the periphery of our study area. Within each group, home ranges of radiocollared individuals overlapped extensively (62.1% ± 26.5% for MCP100; 59.6% ± 23.0% for MCP95; 37.1% ± 24.5% for MCP50), and up to 4 adults per group shared the same burrow (sett). We consider the implications of our data for understanding of mustelid sociospatial behavior. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report the effects of tourist trail on mammals in a developing Protected Area (PA). [•] Mammal signs along transects adjacent to less used, unpaved trails were affected less. [•] Species and guilds exhibited different sign score responses to Trail Type and Use. [•] Paucity of larger mammal signs was associated with greater Trail Use. [•] However, smaller mammals were associated with human-modified forest types. [ABSTRACT FROM AUTHOR]