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Lizard diets are highly diverse and have contributed to the diversification, biogeographical distributions, and evolution of novel traits across this global radiation. Many parts of a lizards ecology-including habitat preferences, foraging modes, predation risks, interspecific competition, and thermal constraints, among others-interact to shape diets, and dietary niche partitioning simultaneously contributes to co-occurrence within communities. We used DNA metabarcoding of fecal samples to identify prey items in the diets of three sympatric Sceloporus lizards in the Madrean Sky Islands of Arizona, USA. We found evidence for dietary niche partitioning between interacting species concomitant with their respective ecologies. We also compared diet composition between populations to understand how conserved or plastic species diets are between different environments. Our findings suggest that habitat generalists are also diet generalists in this system, while the same may be true for specialists. The identification of prey items to much lower taxonomic levels than previously documented further reveals hidden diversity in the diets of these species and underscores the utility of metabarcoding for understanding the full complexity of lizard diets.

The New Mexico Jumping Mouse (Zapus luteus) is a federally endangered granivore active for only 3 to 5 months annually. Knowledge of diet can help guide habitat recovery and yet despite calls for restoration of its riparian habitat, the diet of Z. luteus remains largely unknown. To date, only 8 plant species have been described in the diet—whereas insectivory, mycophagy, and dietary shifts have only been hypothesized. In the late summer, Z. luteus rapidly accumulates fat for a 9-month hibernation and restoration may fail if seasonal variation in the diet is overlooked. We used DNA metabarcoding on fecal DNA (n = 165) to resolve dietary taxa within multiple trophic levels of the diet and investigate monthly patterns of consumption. Seldom studied in metabarcoding frameworks, we also investigated exogenous contamination in Sherman live-capture traps. Potential contamination among feces, pelage, and trap surfaces was detectable but low (median = 0% to 2%), with fecal communities distinct from exogenous sources. The diet of Z. luteus was varied and most frequently (frequency of occurrence) of graminoids, forbs, lepidopterans, dipterids, and false-truffles. For plant foods, dietary diversity increased throughout their season of activity, shifting from sedges and woody vegetation in the early season (June to July) to forbs and grasses in the late season (August to September). Insect consumption was consistently detected throughout the season, whereas mycophagy was more frequently detected in August, when hypogeous fungi are typically more abundant. The breadth of dietary taxa suggests plasticity in resource use, potentially accommodating diverse patterns of seed availability throughout their active period. Shifts in plant consumption may reflect a dietary adaptation to the phenological patterns of their plant communities, a synchrony that might benefit both pre- and post-hibernation survival. Our work substantially improves our understanding of the diet of Z. luteus (241 dietary taxa) and will be useful for guiding habitat recovery. It also offers scalable methods to further investigate the diet under disturbance contexts (e.g. grazing, wildfire, drought). [ABSTRACT FROM AUTHOR]

Bats are prodigious consumers of agricultural and forest pests, and are, therefore, a natural asset for agricultural productivity, suppressing populations of such pests. This study provides baseline information of diet of 143 bats belonging to eight insectivorous bat species from agricultural areas of Rwanda while evaluating the effectiveness of bats as pest suppressors. Using DNA metabarcoding to analyze bat fecal pellets, 85 different insect species were detected, with 60% (n = 65), 64% (n = 11) and 78% (n = 9) found to be agricultural pests from eastern, northern and western regions, respectively. Given the high percentages of agricultural pests detected, we submit that Rwandan insectivorous bats have the capacity for biocontrol of agricultural pests. Rwandan bat populations should be protected and promoted since they may foster higher crop yields and sustainable livelihoods. [ABSTRACT FROM AUTHOR]

The southern hairy-nosed wombat (Lasiorhinus latifrons) is a cryptic, primarily nocturnal marsupial, for which behavioral information is notably lacking. Animals that are difficult to observe can be identified and tracked by individual-specific genotypes obtained from remotely collected DNA sources; wombats are excellent candidates for such an approach because freshly plucked hair is easily captured at burrow entrances. Twice a year during 1999-2001, we employed an intensive remote hair-collection regime coupled with individual-resolution genetic analysis to sample a South Australian population in a 63.3-[km.sup.2] protected conservation reserve. Individuals were identified using 5 highly polymorphic microsatellite markers and further examined using another 10 markers to resolve ambiguities, enabling assessment of burrow- and space-use patterns. Analyses of rate of discovery of new individuals indicated that nearly all wombats inhabiting the study area were detected (102); there were > 1,000 'capture' events, and 90% of individuals were detected multiple times. Surprisingly, a female sex bias existed despite females being the dispersing sex. Space use was conservative and likely a reflection of adaptations enabling energy conservation. Transits between the northern and southern sections of the study area were nearly nonexistent. No sex or consistent seasonal differences were found in burrow, warren, or space use, other than in interaction with other factors. However, a strong increase in activity and space use in September 2001 relative to other sampling periods may be attributed to activities associated with mating. The thoroughness and evenness of this study's sampling strategy was markedly effective for this species, as, with appropriate modification and optimization, it will likely be for other shy and cryptic organisms. Key words: marsupial biology, microsatellites, molecular ecology, noninvasive genetic sampling, space use