Different analytical techniques used on the same data set may lead to different conclusions about the existence and strength of genetic structure. Therefore, reliable interpretation of the results from different methods depends on the efficacy and reliability of different statistical methods. In this paper, we evaluated the performance of multiple analytical methods to detect the presence of a linear barrier dividing populations. We were specifically interested in determining if simulation conditions, such as dispersal ability and genetic equilibrium, affect the power of different analytical methods for detecting barriers. We evaluated two boundary detection methods (Monmonier's algorithm and WOMBLING), two spatial Bayesian clustering methods (TESS and GENELAND), an aspatial clustering approach (STRUCTURE), and two recently developed, non-Bayesian clustering methods [PSMIX and discriminant analysis of principal components (DAPC)]. We found that clustering methods had higher success rates than boundary detection methods and also detected the barrier more quickly. All methods detected the barrier more quickly when dispersal was long distance in comparison to short-distance dispersal scenarios. Bayesian clustering methods performed best overall, both in terms of highest success rates and lowest time to barrier detection, with GENELAND showing the highest power. None of the methods suggested a continuous linear barrier when the data were generated under an isolation-by-distance (IBD) model. However, the clustering methods had higher potential for leading to incorrect barrier inferences under IBD unless strict criteria for successful barrier detection were implemented. Based on our findings and those of previous simulation studies, we discuss the utility of different methods for detecting linear barriers to gene flow.

Bat guano is a relatively untapped reservoir of information, having great utility as a DNA source because it is often available at roosts even when bats are not and is an easy type of sample to collect from a difficult-to-study mammalian order. Recent advances from microbial community studies in primer design, sequencing, and analysis enable fast, accurate, and cost-effective species identification. Here, we borrow from this discipline to develop an order-wide DNA mini-barcode assay (Species from Feces) based on a segment of the mitochondrial gene cytochrome c oxidase I (COI). The assay works effectively with fecal DNA and is conveniently transferable to low-cost, high-throughput Illumina MiSeq technology that also allows simultaneous pairing with other markers. Our PCR primers target a region of COI that is highly discriminatory among Chiroptera (92% species-level identification of barcoded species), and are sufficiently degenerate to allow hybridization across diverse bat taxa. We successfully validated our system with 54 bat species across both suborders. Despite abundant arthropod prey DNA in guano, our primers were highly specific to bats; no arthropod DNA was detected in thousands of feces run on Sanger and Illumina platforms. The assay is extendable to fecal pellets of unknown age as well as individual and pooled guano, to allow for individual (using singular fecal pellets) and community (using combined pellets collected from across long-term roost sites) analyses. We developed a searchable database (http://nau.edu/CEFNS/Forestry/Research/Bats/Search-Tool/) that allows users to determine the discriminatory capability of our markers for bat species of interest. Our assay has applications worldwide for examining disease impacts on vulnerable species, determining species assemblages within roosts, and assessing the presence of bat species that are vulnerable or facing extinction. The development and analytical pathways are rapid, reliable, and inexpensive, and can be applied to ecology and conservation studies of other taxa.

Habitat fragmentation and associated reduced dispersal of wildlife can lead to an accumulation of related individuals in fragments. The altered kin interactions and amplified chance of inbred matings has profound implications for mating and social systems, and ultimately population persistence. Nonetheless, within-fragment population processes are rarely studied. With this aim, we examined relatedness structure in two candidate isolated populations (Kulpara and Scrubby Peak) of southern hairy-nosed wombats (Lasiorhinus latifrons). Wombats were sampled by remote hair-trapping for genotyping at 14 microsatellite loci, enabling individual identification and estimation of space-use and associative behaviour with respect to relatedness. Genetic data indicated that Scrubby Peak was not strongly isolated, against predictions from landscape structure and history. In isolated Kulpara, inhibited female dispersal (normally the dispersing sex) was associated with high population density and altered kin relationships. First, female relatives preferentially coexisted, a radical departure from the previously reported active avoidance of female relatives in continuous habitat. This is consistent with females in altered habitat interacting with more- rather than less-related females to minimize the cost:benefit ratio of proximity to other wombats. Second, inbreeding avoidance appeared to be stronger at Kulpara than in conspecific populations with natural population structures. Although these adaptive behaviours may have contributed to persistence of the Kulpara population in the short term, they are unlikely to ensure its long-term viability in the face of ongoing isolation because they can act only to slow the rate of inbreeding and mitigate some of its negative impacts.

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Spatiotemporal distributions of key resources are hypothesized to underpin sociobiological patterns. Burrow availability and quality is of paramount importance to fossorial animals. The southern hairy-nosed wombat (Lasiorhinus latifrons) burrows in both hard and friable soils. Theoretical and empirical studies suggest that the harder substrate should promote closer geographical clustering of burrows than in softer soils. Clustered burrows are expected to be associated with larger group sizes. If sociality is driven by constraint rather than advantage, patterns of spatial and temporal distribution of animals within and among groups may show indications of avoidance or even antagonism, and 'making the best of a bad job' via positive kin associations to offset the disadvantages of high-density living. To test these ideas, we compared warren relatedness and social structure of L. latifrons on friable soils (Nullarbor Plain) and hard calcrete (Brookfield Conservation Park, BCP). Individuals were sampled by noninvasive collection of hairs for genotyping to identify individuals and to estimate their space-use and associative behaviour with respect to relatedness. Burrows in calcrete were indeed more clumped, and warren and group size larger. Differences in spatiotemporal organization and relatedness structure between sites were in the expected direction: (i) Nullarbor males associated and shared warrens less than at BCP; and (ii) Nullarbor spatial relatedness patterning data were not consistent with proposed female breeding dispersal, in contrast to those at BCP. Under Nullarbor (low density) conditions, cooperation or tolerance between males may be less advantageous, and accessing or digging burrows should be less of a constraint for juvenile females.