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On the Ground • A recent publication by Carter et al. (2017) presents research on the effects of deferred rotation grazing and water provisioning on a suite of environmental variables. • We detail issues that call into question the validity of the results and conclusions reported by the authors. • Data were not collected in a scientifically rigorous way. • Sufficient detail is not presented for the study to be replicated. • The authors do not adhere to standard statistical definitions or assumptions. • The study suffers from unaccounted for pseudoreplication. • The authors draw conclusions beyond the reasonable scope of inference.

Prior to 1900, coyotes (Canis latrans) were restricted to the western and central regions of North America, but by the early 2000s, coyotes became ubiquitous throughout the eastern United States. Information regarding morphological and genetic structure of coyote populations in the southeastern United States is limited, and where data exist, they are rarely compared to those from other regions of North America. We assessed geographic patterns in morphology and genetics of coyotes with special consideration of coyotes in the southeastern United States. Mean body mass of coyote populations increased along a west‐to‐east gradient, with southeastern coyotes being intermediate to western and northeastern coyotes. Similarly, principal component analysis of body mass and linear body measurements suggested that southeastern coyotes were intermediate to western and northeastern coyotes in body size but exhibited shorter tails and ears from other populations. Genetic analyses indicated that southeastern coyotes represented a distinct genetic cluster that differentiated strongly from western and northeastern coyotes. We postulate that southeastern coyotes experienced lower immigration from western populations than did northeastern coyotes, and over time, genetically diverged from both western and northeastern populations. Coyotes colonizing eastern North America experienced different selective pressures than did stable populations in the core range, and we offer that the larger body size of eastern coyotes reflects an adaptation that improved dispersal capabilities of individuals in the expanding range.

The influence of harvest on wild populations has been the focus of substantial debate, and has widespread implications for the management of wild populations. Traditional views of harvest are based on density-dependent responses of populations to harvest. However, alternate mechanisms can and do induce compensation (e.g., individual heterogeneity). Selective harvest of successful females and their offspring is thought to occur in some grouse populations (e.g., blue grouse [Dendragapus spp.], greater sage-grouse [Centrocercus urophasianus]), and delaying harvest within a season has been proposed as a viable strategy to overcome this type of selective harvest. However, a recent examination regarding the effects of harvest on greater sage-grouse strongly criticized the recommendation of delayed harvest. Herein, we address the criticism of the delayed harvest strategy and provide an examination of projecting the effects of harvest in the face of individual heterogeneity using deterministic projection models. We demonstrate that under proportional harvesting strategies, given a fixed harvest rate, early additive harvest does not have a larger effect on the population than additive harvest later in the season. Moreover, we show that when higher quality individuals (i.e., individuals with higher survival and reproductive rates) are more susceptible to harvest, individual heterogeneity in harvest effects will induce depensatory dynamics when density-dependent effects are only additive. Conversely, even when density-dependent effects are additive, if lower quality individuals are more susceptible to harvest, heterogeneity will induce partial compensation. Reducing the selectivity of harvest on higher quality individuals (i.e., shifting harvest onto lower quality groups) could reduce the risk of artificial selection and induce partial compensation. Therefore, we recommend managers consider the spatiotemporal patterns of populations and time harvest to maximize the heterogeneity tradeoff between higher and lower quality individuals. © 2017 The Wildlife Society.

We detected heartworm (Dirofilaria immitis) in 37.2% of 212 coyotes ( Canis latrans ) collected from 28 counties in Florida, US, between February 2010 and April 2014. Adult coyotes had a higher prevalence (45.6% of 103) than juveniles (29% of 80), and there was no significant difference in prevalence between adult male and female coyotes. Adults demonstrated a higher prevalence of heartworm in northern counties (56% of 91) than in southern counties (23.1% of 121) and a higher prevalence in urban areas (58.1% of 31) than in rural areas (33.3% of 63). There was no significant difference in mean body weight between infected and uninfected adult males or females. Intensity ranged from 1 to 144 (x̄ =21.29, SD=23.89, n=77). Mixed-sex heartworm infections were found in 88.9% of positive hosts, where the female-to-male ratio of worms was 1.14:1 (n=27). No pathologic changes attributable to heartworm infection were seen. A subsample of heartworms was confirmed to be D. immitis by targeted PCR amplification and DNA sequencing. Of 25 samples submitted for genotyping eight sequence haplotypes were found, all of which were distinct from all publicly available sequences derived from heartworms collected from domestic dogs ( Canis lupus familiaris). These sequences revealed more polymorphisms than did previous samples of D. immitis, which provides a broader foundation for the possibility that the heartworms will develop resistance to anthelmintics.

Estimating the climatic and habitat factors that affect animal movement patterns (e.g., migration, dispersal, site fidelity) is informative for management and conservation. Juvenile Greater Sage-Grouse (Centrocercus urophasianus) have been identified as having a significant influence on population growth, but relatively little is known about factors that influence survival, movement, and the potential interrelation between the two. Movement out of fall habitat has been suggested to influence the survival of juvenile Greater Sage-Grouse. We reconceptualized the nest survival model (equating movement out of a focal area with failure of a nest) to extend its use to movement data on juveniles in south-central Utah. We found that juveniles' seasonal movements were affected by a linear trend in time (β = −0.655, 95% confidence interval [CI]: −1.049 to −0.26) and by precipitation (β = −3.718, 95% CI: −6.687 to −0.749), with an interaction between the parameters (β = 0.360, 95% CI: 0.002–0.718). In the a...

Occurrence of melanism in the coyote (Canis latrans) has been poorly documented. We collected 244 coyote carcasses throughout Florida during 2011–2014 and documented 18 cases of melanism (7.4%). Melanistic individuals were positively correlated with tree canopy cover (βcanopy mean = 0.11, se = 0.03, P < 0.001) and consequently observed only in northern portions of Florida. However, geographic trends (e.g., northing, easting, north-westing) did not explain variation in our data as well as habitat. Melanism varied through space from locally abundant to absent, but the drivers perpetuating variation in frequency of melanism are likely complex as the mechanisms for polymorphic maintenance are unclear.

Human-mediated range expansions have increased in recent decades and represent unique opportunities to evaluate genetic outcomes of establishing peripheral populations across broad expansion fronts. Over the past century, coyotes (Canis latrans) have undergone a pervasive range expansion and now inhabit every state in the continental United States. Coyote expansion into eastern North America was facilitated by anthropogenic landscape changes and followed two broad expansion fronts. The northern expansion extended through the Great Lakes region and southern Canada, where hybridization with remnant wolf populations was common. The southern and more recent expansion front occurred approximately 40 years later and across territory where gray wolves have been historically absent and remnant red wolves were extirpated in the 1970s. We conducted a genetic survey at 10 microsatellite loci of 482 coyotes originating from 11 eastern U.S. states to address how divergent demographic histories influence geographic patterns of genetic diversity. We found that population structure corresponded to a north–south divide, which is consistent with the two known expansion routes. Additionally, we observed extremely high genetic diversity, which is atypical of recently expanded populations and is likely the result of multiple complex demographic processes, in addition to hybridization with other Canis species. Finally, we considered the transition of allele frequencies across geographic space and suggest the mid-Atlantic states of North Carolina and Virginia as an emerging contact zone between these two distinct coyote expansion fronts.

Many techniques to evaluate survival and movement of wildlife rely on the capture and instrumentation of individuals. However, effective capture techniques for Great Egrets (Ardea alba) outside the breeding season remain elusive, particularly a method to attain robust sample sizes to investigate several aspects of biology. A handheld pneumatic net gun method was developed and successfully captured 97 Great Egrets in 121 trap days. No direct mortalities or substantial injuries occurred. The handheld pneumatic net gun was more cost-effective than commercially available or similar devices, and could prove useful for sensitive species where injury or mortality must be minimized or where the use of explosive devices is restricted.

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) adult hen and juvenile survival have been shown to have significant influence on population growth rates. However, assessing the sensitivity of population growth rates to variability in juvenile survival has proven difficult because of limited information concerning the potentially important demographic rate. Sage-grouse survival rates are commonly assessed using necklace-type radio transmitters. Recent technological advances have lead to increased interest in the deployment of dorsally mounted global positioning system (GPS) transmitters for studying sage-grouse ecology. However, the use of dorsally mounted transmitters has not been thoroughly evaluated for sage-grouse, leading to concern that birds fitted with these transmitters may experience differentialmortality rates. Weevaluated theeffect oftransmitter positioning(dorsal vs.necklace) on juvenile sage-grouse survival using a controlled experimental design with necklace-style and suture-backpack very high frequency (VHF) transmitters. To evaluate theeffects oftemporalvariation, sex, andtransmitter type on juvenile sage-grouse survival, we monitored 91 juveniles captured in south-central Utah from 2008 to 2010. We instrumented 19 females with backpacks, 14 males with backpacks, 39 females with necklaces, and 19 males with necklaces. We used Program MARK to analyze juvenile survival data. Although effects were only marginally significant from a statistical perspective, sex (P ¼0.103) and transmitter type (P ¼0.09) were deemed to have biologically meaningful impacts on survival. Dorsally mounted transmitters appeared to negatively affected daily survival (btransmitter type ¼� 0.55, SE ¼0.32). Temporal variation in juvenile sage- grouse daily survival was best described by a quadratic trend in time, where daily survival was lowest in late September and was high overwinter. An interaction between the quadratic trend in time and year resulted in the low point of daily survival shifting within the season between years (27 vs. 17 Sep for 2008 and 2009, respectively). Overall (15 Aug-31 Mar) derived survival ranged 0.42-0.62 for females and 0.23-0.44 for males. For all years pooled, the probability death was due to predation was 0.73, reported harvest was 0.16, unreported harvest was 0.09, and other undetermined factors was 0.02. We observed 0% and 6.8% crippling loss (from hunting) in 2008 and 2009, respectively. We recommend the adoption of harvest management strategies that attempt to shift harvest away from juveniles and incorporate crippling rates. In addition, future survival studies on juvenile sage-grouse should use caution if implementing dorsally mounted transmitters because of the potential for experimental bias. 2014 The Wildlife Society.

Species conservation efforts often use short‐term studies that fail to identify the vital rates that contribute most to population growth. Although the greater sage‐grouse (Centrocercus urophasianus; sage‐grouse) is a candidate for protection under the U.S. Endangered Species Act, and is sometimes referred to as an umbrella species in the sagebrush (Artemisia spp.) biome of western North America, the failure of proposed management strategies to focus on key vital rates that may contribute most to achieving population stability remains problematic for sustainable conservation. To address this dilemma, we performed both prospective and retrospective perturbation analyses of a life cycle model based on a 12‐yr study that encompassed nearly all sage‐grouse vital rates. To validate our population models, we compared estimates of annual finite population growth rates (λ) from our female‐based life cycle models to those attained from male‐based lek counts. Post‐fledging (i.e., after second year, second year, and juvenile) female survival parameters contributed most to past variation in λ during our study and had the greatest potential to change λ in the future, indicating these vital rates as important determinants of sage‐grouse population dynamics. In addition, annual estimates of λ from female‐based life cycle models and male‐based lek data were similar, providing the most rigorous evidence to date that lek counts of males can serve as a valid index of sage‐grouse population change. Our comparison of fixed and mixed statistical models for evaluating temporal variation in nest survival and initiation suggest that conservation planners use caution when evaluating short‐term nesting studies and using associated fixed‐effect results to develop conservation objectives. In addition, our findings indicated that greater attention should be paid to those factors affecting sage‐grouse post‐fledging females. Our approach demonstrates the need for more long‐term studies of species vital rates across the life cycle. Such studies should address the decoupling of sampling variation from underlying process (co)variation in vital rates, identification of how such variation drives population dynamics, and how decision makers can use this information to re‐direct conservation efforts to address the most limiting points in the life cycle for a given population.

Research on long-lived iteroparous species has shown that reproductive success may increase with age, until the onset of senescence, and that prior reproductive success may influence current reproductive success. Such complex reproductive dynamics can complicate conservation strategies, especially for harvested species. Further complicating the matter is the fact that most studies of reproductive costs are only able to evaluate a single measure of reproductive effort. We systematically evaluated the effects of climatic variation and reproductive trade-offs on multiple reproductive vital rates for greater sage-grouse (Centrocercus urophasianus; sage-grouse), a relatively long-lived galliforme of conservation concern throughout western North America. Based on over a decade of field observations, we hypothesized that reproduction is influenced by previous reproductive success. We monitored hen reproductive activity from 1998 to 2010, and used generalized linear mixed models to assess effects of climate and previous reproductive success on subsequent reproductive success. Reproductive trade-offs manifested as chronic effects on subsequent reproduction and were not apparent in all measures of subsequent reproduction. Neither nest initiation nor clutch size were found to be affected by climatic variables (either year t - 1 or t) or previous reproductive success. However, both nest and brood success were affected by climatic variation and previous reproductive success. Nest success was highest in years with high spring snowpack, and was negatively related to previous brood success. Brood success was positively influenced by moisture in April, negatively associated with previous nest success, and positively influenced by previous brood success. Both positive and negative effects of previous reproduction on current year reproduction were observed, possibly indicating high levels of individual heterogeneity in female reproductive output. Our results support previous research in indicating that climatic variability may have significant negative impacts on reproductive rates.