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Grassland birds have exhibited dramatic and widespread declines since the mid‐20th century. Greater prairie chickens (Tympanuchus cupido pinnatus) are considered an umbrella species for grassland conservation and are frequent targets of management, but their responses to land use and management can be quite variable. We used data collected during 2007–2009 and 2014–2015 to investigate effects of land use and grassland management practices on habitat selection and survival rates of greater prairie chickens in central Wisconsin, USA. We examined habitat, nest‐site, and brood‐rearing site selection by hens and modeled effects of land cover and management on survival rates of hens, nests, and broods. Prairie chickens consistently selected grassland over other cover types, but selection or avoidance of management practices varied among life‐history stages. Hen, nest, and brood survival rates were influenced by different land cover types and management practices. At the landscape scale, hens selected areas where brush and trees had been removed during the previous year, which increased hen survival. Hens selected nest sites in hay fields and brood‐rearing sites in burned areas, but prescribed fire had a negative influence on hen survival. Brood survival rates were positively associated with grazing and were highest when home ranges contained ≈15%–20% shrub/tree cover. The effects of landscape composition on nest survival were ambiguous. Collectively, our results highlight the importance of evaluating responses to management efforts across a range of life‐history stages and suggest that a variety of management practices are likely necessary to provide structurally heterogeneous, high‐quality habitat for greater prairie chickens. Brush and tree removal, grazing, hay cultivation, and prescribed fire may be especially beneficial for prairie chickens in central Wisconsin, but trade‐offs among life‐history stages and the timing of management practices must be considered carefully., Greater prairie chickens (Tympanuchus cupido pinnatus) are considered an umbrella species for grassland conservation and are frequent targets of management, but their responses to land use and management can be quite variable. We examined habitat, nest‐site, and brood‐rearing site selection by hens and modeled effects of land cover and management on hen, nest, and brood survival. Collectively, our results highlight the importance of evaluating responses to management efforts across a range of life‐history stages and suggest that a variety of management practices are likely necessary to provide structurally heterogeneous, high‐quality habitat for greater prairie chickens.

Under Wisconsin state law, the greater prairie chicken (GRPC; Tympanuchus cupido pinnatus) has been listed as a threatened species since 1976. In 2014-15, we conducted a pilot study to determine the prevalence and intensity of gapeworms (Syngamus spp.) in female Wisconsin GRPCs collected from 2 monitored populations. We captured 62 female GRPCs using walk-in-style traps for females and night lighting for juveniles ≥45 days of age. From these individuals, we collected 15 carcasses of radio-marked birds, most of whom died due to predation events. Through dissection, we identified gapeworm in 20% of examined carcasses and report an intensity ranging between 4 and 74 worms.

Effective management of wildlife requires a full understanding of population dynamics and knowledge of potential drivers that influence population growth. The Ruffed Grouse (Bonasa umbellus) is a popular upland game bird widely distributed across the northern United States and Canada that has experienced population declines within portions of its range in response to forest maturation and habitat loss. Although the species has been extensively studied, few efforts have been made to synthesize demographic data into a sensitivity analysis to guide management actions. We reviewed the literature and compiled Ruffed Grouse vital rates from 14 field studies conducted across four decades (1982–2018) within the Upper Great Lakes region of Michigan, Minnesota, and Wisconsin, USA. We parameterized a deterministic matrix model to evaluate population dynamics and conducted sensitivity analyses to identify vital rates projected to have the greatest influence on the finite rate of population change (λ). Our modeling effort projected a stable but highly variable annual rate of population change (λ = 1.01; 95% CI = 0.88–1.14) for Ruffed Grouse in the Upper Great Lakes region. Stochastic rates of population change derived from spring drumming surveys (λ = 1.01; 95% CI = 0.61–1.45) and Christmas Bird Count surveys (λ = 0.99; 95% CI = 0.62–1.76) of the corresponding regional population provided validation of stable trends over the same time period as our demographic model. Prospective elasticities and variance-scaled sensitivities suggested λ would be greatly influenced by components of reproductive performance: nesting success, chick survival, and post-fledging juvenile survival. Retrospective analysis indicated that much of the overall variability in λ and annual productivity was also attributed to annual variation in nesting success. Management of this species has often focused on fall and overwinter survival, but population projection models provided little evidence that survival was the predominant factor affecting population growth of Ruffed Grouse in this region. A suite of confounding factors and demographic processes that drive population trends can differ significantly across a species' range. In the Upper Great Lakes region, management efforts aimed at maximizing reproductive success would likely have the greatest potential influence on Ruffed Grouse population growth. Other types of systematic, regional survey data can also be useful for validating population trends derived from demographic modeling studies.LAY SUMMARYThe Ruffed Grouse (Bonasa umbellus) has been extensively studied, but few efforts have been made to synthesize demographic data into a sensitivity analysis to guide management.A comprehensive understanding of life history traits and vital rates that influence population growth is crucial for maximizing wildlife conservation and management efforts.We summarized Ruffed Grouse vital rates from field studies within the Upper Great Lakes region of Michigan, Minnesota, and Wisconsin, USA, to evaluate population growth.Our analyses projected a stable but highly variable annual rate of population change for Ruffed Grouse in the Upper Great Lakes region.Management efforts aimed at maximizing reproductive success, particularly nesting success and chick survival, would likely have the greatest potential influence on Ruffed Grouse population growth.

Here, we develop scaling laws for (1) the distribution of impact-induced heat within the mantle and (2) shape of the impact-induced melt based on more than 100 smoothed particle hydrodynamic (SPH) simulations. We use Legendre polynomials to describe these scaling laws and determine their coefficients by linear regression, minimizing the error between our model and SPH simulations. The input parameters are the impact angle $\theta$ ($0^{\circ}, 30^{\circ}, 60^{\circ}$, and $90^{\circ}$), total mass $M_T$ ($1M_{\rm Mars}-53M_{\rm Mars}$, where $M_{\rm Mars}$ is the mass of Mars), impact velocity $v_{\rm imp}$ ($v_{\rm esc} - 2v_{\rm esc}$, where $v_{\rm esc}$ is the mutual escape velocity), and impactor-to-total mass ratio $\gamma$ ($0.03-0.5$). We find that the equilibrium pressure at the base of a melt pool can be higher (up to $\approx 80 \%$) than those of radially-uniform global magma ocean models. This could have a significant impact on element partitioning. These melt scaling laws are publicly available on GitHub ($\href{https://github.com/mikinakajima/MeltScalingLaw}{https://github.com/mikinakajima/MeltScalingLaw}$)., Comment: Published in Earth and Planetary Science Letters

The eastern wild turkey (Meleagris gallopavo silvestris) is an economically important upland game bird that has been successfully reintroduced in Wisconsin, USA, and now occurs across the entire state. Although populations have become relatively stable across much of the state, recent concerns have been expressed regarding a plateau in total harvest and declines in local abundance across some areas. Current ecological and demographic parameters are needed to develop biologically justifiable and efficient management strategies. To address these concerns, we used demographic data collected during recent studies on wild turkey survival and productivity in 2 contrasting landscapes with differing proportions of forest and open cover. We then used the properties of deterministic matrix models to identify parameters predicted to have the greatest effect on the finite rate of population change (λ) in both landscapes. Our analyses projected population decline for turkeys in predominately forested landscapes (λ = 0.782) and population increases in more open landscapes (λ = 1.112). Variance-scaled sensitivities suggested that λ was most sensitive to variation in nest and poult survival for populations in both landscapes. A life-table response experiment further indicated that higher λ in open landscapes was largely attributable to greater rates of yearling and adult female survival during the nesting and brood-rearing period. Simulated variations suggest manipulations in female harvest during the fall either-sex season had less impact on λ than did alterations in components of fecundity. Our model results indicated that wild turkey population growth varies across landscapes in southwest and west-central Wisconsin. Management practices that address factors influencing components of fecundity likely have the greatest effect on λ in both landscapes. Additionally, populations in forested landscapes may require more conservative harvests to enhance female survival if population stability or increase is to be realized. © 2014 The Wildlife Society.

Eastern wild turkeys (Meleagris gallopavo silvestris) have colonized the entire state of Wisconsin, USA since being successfully reintroduced in the 1970s. Recently, conservation groups have expressed concerns regarding habitat quantity and quality in association with population plateaus and declines in local abundance in some portions of the state. Estimates of survival and productivity are needed to identify the current population status and for drafting effective management plans. We evaluated female eastern wild turkey demographic parameters and the relationship of these parameters to landscape composition between townships that were forest-dominated and those that were primarily open (e.g., cropland, pasture) in southwest and west-central Wisconsin. We radiomarked 129 female eastern wild turkeys during a 2-year field study (2010–2012). Seasonal variation and landscape effects on survival were important components in our top models, which accounted for >98% of the relative support. Seasonal survival (±SE) was lowest during spring (15 Mar–18 Jul) across both landscapes (0.672 ± 0.039). The model-averaged estimate of annual (15 Mar–14 Mar) female survival across all study townships was 0.515 ± 0.035 and survival estimates were lower in forested landscapes (2010 = 0.450 ± 0.075, 2011 = 0.279 ± 0.094) than in open landscapes (2010 = 0.707 ± 0.053, 2011 = 0.651 ± 0.045). Predation accounted for 77.8% of all mortalities and was highest during spring; predator-related mortalities were more frequent in forested townships (P = 0.027). Nest survival was similar in forested landscapes (θˆ=0.273±0.08) and open landscapes (θˆ=0.201±0.07). Additionally, we estimated apparent nesting success to be 0.256 ± 0.04 and it was not different between landscapes (P = 0.573). Poult survival was lower in forested landscapes compared to open landscapes at 4 weeks post-hatch (P = 0.008). Differences in eastern wild turkey population demographics may exist in separate local populations that are in close albeit different types of landscapes. Management of eastern wild turkeys that enhances female and poult survival during the nesting and brood-rearing periods can greatly influence population growth, particularly in forest-dominant landscapes. © 2014 The Wildlife Society.

Supplemental translocations to small, isolated populations can be a valuable strategy to counteract the effects of genetic drift by increasing genetic diversity. We studied the genetic consequences of a translocation of greater prairie-chickens (Tympanuchus cupido pinnatus) to Wisconsin, which has a small population (

We examined the influence of woody vegetation on reclaimed surface mines on relative abundance of Grasshopper Sparrows (Ammodramus savannarum), Henslow's Sparrows (A. henslowii), Eastern Meadowlarks (Sturnella magna), Savannah Sparrows (Passerculus sandwichensis), Bobolinks (Dolichonyx oryzivorus), and Dickcissels (Spiza americana) as well as nest-site selection and nesting success of Grasshopper and Henslow's sparrows and Eastern Meadowlarks. Grasshopper and Henslow's sparrows were the most abundant grassland species on reclaimed mines. Numbers of Grasshopper, Henslow's, and Savannah sparrows, and Bobolinks were negatively associated with percent cover of woody vegetation within 100 m of survey locations. Only Grasshopper Sparrows responded to woody vegetation at nest-patch scales, as random locations had >2.5 times as much woody cover as nest locations. Daily nest survival (DNS) was negatively associated with amount of woody vegetation within 100 m of Grasshopper (DNS 0.76 ± 0.001 SE) and Hensl...