Effective wildlife management often relies on estimates of animal density, and cue counting is a viable estimation strategy.A key component of density estimation from dung, a form of cue counting, is estimation of the persistence time, t ^, of dung piles. However, differences between observers on what constitutes a dung pile may alter subsequent density estimates.Additionally, many researchers studying white-tailed deer (Odocoileus virginianus) have substituted for t ^the number of days between the date in which 98% of deciduous trees shed leaves in autumn and field sampling. To address these 2 concerns, we compared 3 methods for estimating t ^of whitetailed deer pellet groups: (1) a common modelling approach based on observations from a single observer (single-observer method), (2) a method that accommodates interobserver variation on the status of dung during field surveys (interobserver method), and (3) the days elapsed since 98% of deciduous trees shed autumn leaves (leaf-off method). We then applied these 3 t ^estimates to distance-sampling data on pellet groups from white-tailed deer that we collected along transects during 3 sampling seasons from 2019-2021 in westcentral Indiana. We estimated habitat-and year-specific deer densities. Persistence probability of pellet groups varied across habitats and years, positively with age and number of pellets, and negatively with precipitation and temperature. In several instances, we found strong or marginal differences between densities estimated using the leaf-off method and the other

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Oak (Quercus) species are prominent in southern US forests. The ability to recycle nitrogen (N) during dormancy is an important adaptation to conserve a limited resource, but N resorption in southern oaks is not well understood. Leaf protein and chlorophyll are both degraded during senescence to release N that can be stored in stems and roots. We hypothesized that leaf N would decrease soon after degradation of leaf protein and/or chlorophyll. Chlorophyll, protein, and N content were measured in leaves of Q. texana, Q. phellos, and Q. nigra during fall 2016 and 2017, in Arkansas. Degradation of protein, which holds the majority of leaf N, started early, in September, whereas chlorophyll degradation and N export from leaves occurred in late November. The delay between protein degradation and N export indicates that N resorption is drawn out over months in southern oaks, because of an unknown mechanism. Protracted leaf senescence could be due to a physiological or biochemical constraint, or it could be an adaptive trait where fall is typically warm and water-limited, but occasionally wet. Our results lay a foundation for future studies to examine how environmental stress may affect nutrient resorption during leaf senescence in southern oak species.

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