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We present the California‐Nevada Adjoint Simulations (CANVAS) model, an adjoint waveform tomography model of the crust and uppermost mantle of the states of California and Nevada. We used WUS256 (Rodgers et al., 2022, https://doi.org/10.1029/2022jb024549) as the starting model and iteratively decreased the minimum period of CANVAS from 30 to 12 s. CANVAS was iterated in two distinct stages: the first stage with source mechanisms from the Global Centroid Moment Tensor (GCMT) catalog and the second stage with inverted moment tensors (MT) using the CANV_WUS model (Doody et al., 2023, https://doi.org/10.1029/2023jb026463). We show that updating the MTs with 3D Green's functions improved waveform fits and azimuthal coverage of windowed data used to calculate the gradients. As for the model itself, we improved waveform fits over WUS256, particularly in the dispersed surface waves. CANVAS resolved tectonic features seen in other models and accurately defined the depth to basement of major basins, including the Central Valley and the Ventura Basin. We propose CANVAS as a starting model for crustal tomography models on smaller scales. Plain Language Summary: California sits at the boundary of three tectonic plates and a large portion of the population lives in areas of high seismic hazard. Understanding earthquake ground shaking requires accurate models of the Earth's interior. We present a full waveform inversion (FWI) seismic wavespeed model of California and Nevada. FWI determines Earth structure by modeling wave propagation to optimize the fit of synthetic data to observed data from recorded earthquakes. We ran 161 iterations on a high‐performance computing (HPC) system to produce the California‐Nevada Adjoint Simulations (CANVAS) model, which used data with a minimum period of 12 s. Using an intermediate version of the model, we inverted for earthquake source parameters and showed that updating sources contribute to accurately modeling waveforms at shorter periods. The final version of CANVAS agrees with previous studies on tectonic structure and resolved the depth to basement of major basins in California. We propose that CANVAS be used as a starting model for other regional studies of California and Nevada. Key Points: We present an adjoint waveform tomography model of California and Nevada iterated for 161 iterations down to a minimum period of 12 sCANVAS resolves known tectonic structures and can accurately constrain depths to basement of major basins in CaliforniaWe propose CANVAS as a high‐quality starting model for smaller‐scale regional tomography studies [ABSTRACT FROM AUTHOR]

Adult female survival and calf recruitment influence population dynamics, but there is limited information on calving and neonatal mortality of boreal woodland caribou (Rangifer tarandus caribou; caribou) in Ontario, Canada. We identified calf parturition sites and 5‐week neonatal mortality using a movement‐based approach across 3 northern Ontario study regions (Pickle Lake, Nakina, and Cochrane) that vary in their capacity to support caribou populations. In comparing 22 caribou‐years of video‐collar footage during 2010–2013 to predictions of the movement‐based approach, we found live parturition events were 100% correctly classified, date of parturition was within 1.08 ± 0.28 (x¯ ± SE) days, and mortality events up to 5 weeks postpartum were 88% correctly classified. Across study regions, 87% of 186 caribou were pregnant and 76% of 107 caribou‐years indicated birth events with median parturition dates a week later in Cochrane (23 May) than in Pickle Lake (17 May) and Nakina (16 May). Based on selection ratios of caribou‐years with calves‐at‐heel (n = 80), caribou consistently selected for lowlands and closed‐canopied forests and mostly against early‐seral stands (<20 yrs old) and areas near linear features during the neonatal and the post‐neonatal period (up to 35 days postpartum). Based on the video footage and movement models, 30% of 81 caribou‐years that indicated live births also showed females lost their calf within the first 5 weeks postpartum, with higher risk of neonatal mortality associated with increased use of lowlands and greater postpartum movement rates. This study provides informative metrics of caribou reproduction across northern Ontario that will contribute to future population modeling and identifies important landscape features to be considered in future industrial development and land use planning for caribou conservation. © 2020 The Wildlife Society. Parturition and neonatal mortality rates can be predicted accurately from movement rates. Caribou selected calving (neonatal and post‐neonatal) areas to minimize predation risk, but greater use of lowlands and increased movement rates postpartum increased risk of neonatal mortality. [ABSTRACT FROM AUTHOR]

While the acoustic waveform inversion method is increasingly used in geophysical acoustics to constrain source parameters, the inversion results are often provided without any uncertainty analysis. This study presents a probabilistic representation for acoustic waveform inversion and method to evaluate the inversion uncertainty using ground-truth data. A posteriori probability distribution of source estimate is described by a priori waveform misfit covariance and the variance of acoustic source model. The probabilistic framework is applied to local explosion infrasound to estimate the yields of explosions and uncertainty. Estimated yields showed overall good agreement with the true yields (less than 25% errors). The uncertainty of the estimated yield is represented by the sum of the waveform inversion uncertainty and source model uncertainty. It is shown that the yield uncertainty attributed to local infrasound inversion (within 10 km) is as small as the uncertainty caused by 10% prediction errors in the acoustic source model. These results indicate that the acoustic source model uncertainty should also be considered for accurate yield estimation and that local infrasound can be a valuable tool to understand the magnitude of the source uncertainty. [ABSTRACT FROM AUTHOR]

Abstract: Local infrasound is widely used to constrain source parameters of near‐surface events (e.g., chemical explosions and volcanic eruptions). While atmospheric conditions are critical to infrasound propagation and source parameter inversion, local atmospheric variability is often ignored by assuming homogeneous atmospheres, and their impact on the source inversion uncertainty has never been accounted for due to the lack of quantitative understanding of infrasound variability. We investigate atmospheric impacts on local infrasound propagation by repeated explosion experiments with a dense acoustic network and in situ atmospheric measurement. We perform full 3‐D waveform simulations with local atmospheric data and numerical weather forecast model to quantify atmosphere‐dependent infrasound variability and address the advantage and restriction of local weather data/numerical weather model for sound propagation simulation. Numerical simulations with stochastic atmosphere models also showed nonnegligible influence of atmospheric heterogeneity on infrasound amplitude, suggesting an important role of local turbulence. [ABSTRACT FROM AUTHOR]

Abstract: We performed fully deterministic broadband (0–4 Hz) high‐performance computing ground motion simulations of a magnitude 7.0 scenario earthquake on the Hayward Fault (HF) in the San Francisco Bay Area of Northern California. Simulations consider average one‐dimensional (1‐D) and three‐dimensional (3‐D) anelastic structure with flat and topographic free surfaces. Ground motion intensity measures (GMIMs) for the 3‐D model display dramatic differences across the HF due to geologic heterogeneity, with low wave speeds east of the HF amplifying motions. The median GMIMs agree well with Ground Motion Prediction Equations (GMPEs); however, the 3‐D model generates more scatter than the 1‐D model. Ratios of 3‐D/1‐D GMIMs from the same source allow isolation of path and site effects for the 3‐D model. These ratios show remarkably similar trends as site‐specific factors for the GMPE predictions, suggesting that wave propagation effects in our 3‐D simulations are on average consistent with empirical data. [ABSTRACT FROM AUTHOR]

Vertical stratification in the low atmosphere impacts near-ground sound propagation. On clear days, for example, negative gradients of low-atmospheric temperature can lead to upward refraction of acoustic waves and create a zone of silence near the ground, where no acoustic rays can arrive. We investigate impacts of lower tropospheric temperature and wind-velocity gradient on acoustic wave propagation using numerical simulations. Sound refraction in the atmosphere is a frequency-dependent wave phenomenon, and therefore classical ray methods based on infinite-frequency approximation may not be suitable for modeling acoustic wave amplitudes. In this study, a full-waveform acoustic solver was used to predict amplitudes of acoustic waves taking into account meteorological conditions (temperature, pressure and wind). Local radiosonde sounding data were input into acoustic simulations to characterize the background conditions of the local atmosphere. The results of numerical modeling indicate that acoustic overpressure amplitudes were significantly affected by local atmospheric wind speed and direction near the ground. Local wind changes the effective sound speed profile in the atmosphere and influences overpressure amplitude decay governed by upward refraction. We compared 3-D finite-difference modeling results with acoustic overpressure measurements from the Humming Roadrunner explosion experiments conducted in New Mexico in 2012. The modeling results showed good agreement with the observations in peak amplitudes when a background wind was weak and well characterized by local atmospheric data. However, when a strong wind was present at an explosion and its variability was poorly characterized by local radiosonde sounding, the numerical prediction of local acoustic amplitude agreed poorly with the observations. Additional numerical simulations with the inclusion of surface wind data indicate that local acoustic amplitudes could be significantly variable depending on near-ground wind changes. [ABSTRACT FROM AUTHOR]

Both declining and increasing moose (Alces alces) populations have been reported across North America over the last decade. We surveyed all jurisdictions with extant moose populations to determine the extent of these population trends. In 2014-2015, the North American moose population was estimated at ~1,000,000 animals distributed in 30 jurisdictions, which is unchanged since the turn of the century. Populations occurred in 12 Canadian provinces or territories, and in at least 18 states. In the past 5 years, moose density is believed to be increasing in 9, relatively stable in 8, and declining in 11 jurisdictions; estimates of change were unavailable in 2 jurisdictions. In 2014-2015, an estimated 425,537 licensed moose hunters harvested 82,096 moose in 23 jurisdictions. Hunter numbers increased by 39,118, whereas total harvest remained virtually unchanged from a decade earlier. Harvests by Indigenous and subsistence users, although largely unquantified, are believed substantial and important to quantify in certain jurisdictions. A variety of active and passive harvest strategies used to manage moose are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Habitat-based prediction of population density relies on relationships between landscape configuration (i.e., abundance of land-cover types) and equilibrium density. This may be accomplished by estimating resource selection probability functions (RSPFs) based on presence-absence data, or by relating carrying capacity to landscape covariates. We used RSPFs for moose ( Alces alces) from 2 study sites and carrying capacities from 34 wildlife management units across northern Ontario, Canada, to create 2 estimators of moose density. We compared the predictions of both models to moose density in a novel site obtained via aerial census. We also projected the RSPF across 34 management units and compared predicted density to estimated carrying capacity of each unit. The RSPF and carrying capacity models predicted moose equilibrium densities that were statistically indistinguishable from the estimated density of moose at the novel study site, but the carrying capacity model generated uninformatively broad prediction intervals. The RSPF failed to predict carrying capacities in management units across Ontario; however, the differences between RSPF estimates and carrying capacities varied predictably with differences in covariates related to forage availability, suggesting habitat selection strength and RSPF transferability vary with landscape quality. Estimating densities using RSPFs relies on a consistent relationship between habitat selection and animal density; thus, RSPF applicability across space will depend heavily on similarity between the novel and original sites. Demographic projection benefits from broad spatiotemporal datasets that improve reliability but that are relatively rare and subject to broad error. Our findings suggest that selection-based population estimation is preferable to demographically based models because of increased precision of estimates, the immediacy of available data (e.g., single survey or radio-telemetry in multiple sites vs. many generations of population estimates in a time series across space), and the capacity to predict fine-scale patterns of distribution and abundance. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

ABSTRACT We tracked 122 female moose in northwestern Ontario, Canada, using global positioning system (GPS) radio-collars between 1995 and 2001. We used step-selection functions (SSF) to evaluate changes in moose habitat selection as a function of temperature across seasons (summer and winter), stand types, and stand heights. We obtained mean activity levels of moose within stand types and across seasons from motion sensors in the collars. Selection increased for aquatic stand types as a function of temperature across both summer and winter. Selection for stand height was also temperature-dependent, with tall stands being most favored at warm temperatures and least favored at cold temperatures. Moose activity levels increased slightly at higher temperatures during the winter but were mostly constant, whereas summer activity declined significantly with increasing temperature. Seasonal activity levels were mostly constant within habitats, but activity was consistently higher in aquatic habitats compared to woody habitats, with the highest mean activity levels observed when moose were located in open water and marshes during the summer. Our findings corroborate the work of others that moose primarily select habitat based on documented foraging requirements, whereas they may alter mid-day selection for specific stand types providing thermal cover under varied temperatures, indicating a behavioral response to thermoregulatory needs. Increased activity levels at low summer temperatures, and in habitats found to provide thermal cover, support the conclusion that moose may alter their activity to alleviate heat stress, and that temperature-mediated changes in habitat selection may facilitate otherwise energetically costly behavior (e.g., movement). © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Delineating demographic structure across an organism's range can reveal the extent to which population dynamics in different geographic areas are driven by local or external factors and can be crucial for effective conservation and management. Obtaining optimal data for such analyses can be time and resource-intensive and impending development and resource extraction pressures may necessitate the examination of existing data, even when they are less than ideal. We analyzed a historic telemetry dataset containing satellite radio-collar locations of 73 forest-dwelling woodland caribou in northern Ontario to determine demographic structure. We applied several clustering methods (i.e., agglomerative, divisive and fuzzy k-means) to median seasonal locations. Results were used to distinguish demographic units and minimum convex polygons and fixed-kernel density estimates were used to delineate unit boundaries and core areas. For areas where sampling was considered representative of the distribution of caribou on the landscape, we assessed demographic distinctness by evaluating intra-individual variation in cluster membership, membership strength and distance between boundaries and core areas of adjacent units. The number and composition of clusters identified was similar among methods and caribou were grouped into 6 general clusters. The distinctions between the three clusters identified in the central portion of the province (i.e., Lac Seul, Wabakimi, Geraldton) and the two clusters identified in the eastern portion of the province (i.e., Cochrane and Cochrane-Quebec) were determined to represent demographic structuring. Additional distinctions in other areas (i.e., between The Red Lake and Lac Seul clusters in the west and between the central and eastern clusters) may just be artifacts of the original sampling effort. Amongst demographic units, there was no evidence of individual flexibility in cluster membership and average membership strength was very high. There was little to no overlap between boundaries and core areas of adjacent units, but distances between adjacent unit boundaries were relatively low. Additional sampling effort is needed to further delineate demographic structure in Ontario caribou. [ABSTRACT FROM AUTHOR]

We evaluated three methods of estimating population size of woodland caribou (boreal ecotype) on the Slate Islands in northern Ontario. Located on the north shore of Lake Superior, the Slate Islands provide a protected and closed population with very limited predator influence that is ideal for a comparison of survey methods. Our objective was to determine the costs and benefits of three population estimation techniques: (1) forward looking infrared (FLIR) technology to count the number of caribou on regular-spaced transects flown by fixed-wing aircraft; (2) observers to count the number of caribou seen or heard while walking random transects in the spring; and, (3) mark-recapture sampling of caribou pellets using DNA analysis. FLIR and the genetics 3-window approach gave much tighter confidence intervals but similar population estimates were found from all three techniques based on their overlapping confidence intervals. There are various costs and benefits to each technique that are discussed further. Understanding the costs and benefits of different population estimation techniques is necessary to develop cost-effective programs for inventorying and monitoring this threatened species not only on the Slate Islands but for other populations as well. [ABSTRACT FROM AUTHOR]

Traditionally, seasons for animals have been designated based on single external variables such as climate or plant phenology, rather than an animal's response to the dynamic environments within which it lives. By interpreting a rate of movement function of cumulative movement through time we established a method that distinguishes transitions between behaviors limited by winter habitat conditions from those present during summer. Identification of these time periods provides temporal definition to subsequent home-range analyses and use- availability comparisons. We used location data from 32 Global Positioning System-collared female moose (Alces alces) to demonstrate the method. We used model selection (Akaike's Information Criterion) to differentiate between candidate rate of movement response curves. Of 32 moose, 29 clearly conformed to an annual movement pattern described by a logistic curve, with increased rates of movement in summer compared to winter. Conversely, 3 aberrant individuals did not alter their movement rate through the year and were best fit with a linear response curve. The seasonal rate of movement model we developed suggests an average summer period of 122 days (median = 119 days, range = 96-173 days) for moose in northwestern Ontario, Canada. The rate of movement model we applied to individuals indicated 1 May as the median date for the winter-summer transition (range = 2 Apr-24 May), and the median transition from summer to winter was 25 August (range = 1 Aug-23 Oct). Wide variation in timing and duration of summer and winter seasons among individuals demonstrates potential failure of the single external variable approach to capture the suite of factors potentially influencing animal behaviors. By plotting cumulative distance moved throughout the year, we elucidated individual variation in response to known and unknown variables that affect animal movement. Accounting for variability among individuals in designation of biologically significant temporal boundaries is critical to delineation of seasonally important habitats for conservation and sustainability of healthy wildlife populations. [ABSTRACT FROM AUTHOR]

Abstract: The Red Sea Rift, an archetype of a newly formed ocean basin, is an ideal environment in which to study the controversial processes associated with continental rifting. Different models have been proposed to explain how rifting in the Red Sea evolved; however, accurate constraints on lithospheric structure have not been available to discriminate rifting models. We use the S-wave receiver function technique to produce the first images of the lithosphere–asthenosphere boundary (LAB) structure along the Red Sea and throughout the Arabian Peninsula. Lithospheric thickness varies considerably, with thin lithosphere centered on the rift axis, thickening toward the Arabian interior. Gravity data are well fit by our structural model and indicate that high surface topography along the rift flank is not in isostatic equilibrium, requiring dynamic compensation for its support. While our derived structure is consistent with active rifting processes, previous studies demonstrated that the Red Sea initiated as a passive rift. Therefore, our results suggest a two-stage rifting history, where extension and erosion by flow in the underlying asthenosphere are responsible for variations in LAB depth. LAB topography guides asthenospheric flow beneath western Arabia and the Red Sea, demonstrating the important role lithospheric variations play in the thermal modification of tectonic environments. [Copyright &y& Elsevier]

Abstract: A moderate (M ∼5) earthquake struck the northeastern United Arab Emirates (UAE) and northern Oman on March 11, 2002. The event was felt over a wide area of the northern Emirates and was accompanied by smaller (felt) events before and after the March 11 main shock. The event was large enough to be detected and located by global networks at teleseismic distances. We estimated focal mechanism and depth from broadband complete regional waveform modeling. We report a normal mechanism with a slight right-lateral strike-slip component consistent with the large-scale tectonics. The normal component suggests relaxation of obducted crust of the Semail ophiolite (specifically, the Khor Fakkan Block) while the right-lateral strike-slip component of the mechanism is consistent with shear across the Oman Line. Felt earthquakes are rare in the region, however no regional seismic network exists in the UAE to determine local seismicity. This event offers a unique opportunity to study the active tectonics of the region as well as inform future studies of seismic hazard in the UAE and northern Oman. [Copyright &y& Elsevier]

Moose-vehicle collisions are a serious concern in many areas of North America and Fennoscandia. In northwestern Ontario, more than 400 moose-vehicle collisions occur annually, and 26 fatal collisions have occurred over the last 10 years. To avoid colliding with a moose, a motorist must: (1) successfully see or detect the presence of the animal; (2) determine whether or not the moose poses a threat requiring evasive action; (3) determine what action, if necessary, is required; and (4) implement the action. Whereas perception-reaction times of motorists have been studied in detail, allowing calculations of post-detection distances travelled by a vehicle at different speeds, distances at which a moose can first be seen by a driver at night are unknown. We used a full-size moose decoy to determine the distances at which an animal could be detected at night when it was positioned on each shoulder and in the middle of a highway using high and low beam headlamp settings of different vehicles. Overall, we found the mean detection distance across all vehicle types, headlamp settings, and moose decoy locations to be 105 m (range: 23-210 m). Headlamp setting was a significant factor; on the low beam setting, mean detection distance was 74 m and on the high beam setting it was 137 m. Moose decoy location was also important; combining the data for both headlamp settings, mean detection distances were 89 m, 93 m, and 133 m for the left, right, and centre positions, respectively. There was no relationship between headlamp height of different vehicles and moose detection distance. Comparing our results with previously known perception-reaction times of motorists, we determined that drivers travelling at night in excess of about 70 km/h are very likely to be overdriving the illumination capabilities of their headlamps for moose encounters. For drivers using a low beam headlamp setting, the maximum safe speed drops to about 60 km/h and on high beam setting, rises to about 80-90 km/h. These results suggest that along highway corridors where collisions with motor vehicles present a serious threat to public safety and may have significant impacts on local moose populations, speed limits should be set no higher than 70 km/h at night. [ABSTRACT FROM AUTHOR]

Studies the lithosperic structure of the Arabian shield and platform from regional waveform modelling and surface wave velocities. Indication of the lithospheric structures on the Arabian Platform crustal thickness; Composition of the Arabian Platform crust; Implication of the Poisson ratio on the Arabian shield associated with Red Sea for continental volcanism.

Presents a study on the performance of Global Positioning Systems (GPS) collars under the controlled canopy conditions of the Thunder Bay experimental forest. Study areas and research methods; Management implications; Statistical data.

Evaluates the use of an automated animal location system based on Global Positioning System (GPS) technology for wildlife research. Variation in positional accuracies; Influence of habitat on GPS-collar performance under canopy conditions; Location errors in three-dimensional mode.

Discusses the use of spatial and temporal resolution of the Global Positioning System (GPS) data to study the interactions of animals and their habitat. Increase in the use of GPS to increase the volume locational data accumulated by researchers; Selection and comparisons of home-range estimates.

Reports on the use of NAVSTAR Global Positioning System (NAVSTAR GPS) based telemetry system to monitor the moose population of Ontario. Introduction of the Timber Management Guidelines for the Provision of Moose Habitat; Limitations of VHF-based animal-location systems; Reconfiguring GPS-based animal-borne units.

Wildlife models focused solely on a single strong influence (e.g., habitat components, wildlife harvest) are limited in their ability to detect key mechanisms influencing population change. Instead, we propose integrated modeling in the context of cumulative effects assessment using multispecies population dynamics models linked to landscape‐climate simulation at large spatial and temporal scales. We developed an integrated landscape and population simulation model using ALCES Online as the model‐building platform, and the model accounted for key ecological components and relationships among moose (Alces alces), grey wolves (Canis lupus nubilus), and woodland caribou (Rangifer tarandus caribou) in northern Ontario, Canada. We simulated multiple scenarios over 5 decades (beginning 2020) to explore sensitivity to climate change and land use and assessed effects at multiple scales. The magnitude of effect and the relative importance of key factors (climate change, roads, and habitat) differed depending on the scale of assessment. Across the full extent of the study area (654,311km2 [ecozonal scale]), the caribou population declined by 26% largely because of climate change and associated predator‐prey response, which led to caribou range recession in the southern part of the study area. At the caribou range scale (108,378 km2), which focused on 2 herds in the northern part of the study area, climate change led to a 10% decline in the population and development led to an additional 7% decline. At the project scale (8,331 km2), which was focused more narrowly on the landscape surrounding 4 proposed mines, the caribou population declined by 29% largely in response to simulated development. Given that observed caribou population dynamics were sensitive to the cumulative effects of climate change, land use, interspecific interactions, and scale, insights from the analysis might not emerge under a less complex model. Our integrated modeling framework provides valuable support for broader regional assessments, including estimation of risk to caribou and Indigenous food security, and for developing and evaluating potential caribou recovery strategies. © 2021 The Wildlife Society. : Boreal woodland caribou in northern Ontario, Canada, are sensitive to climate change and land use because of direct effects to habitat and indirect effects by way of the moose‐wolf‐caribou system. We present an integrated modeling framework with sufficient complexity to assess multispecies population dynamics across large spatial scales that would provide support for project‐level, range level, and regional assessments and planning, including assessment of risk to caribou sustainability and Indigenous food security and for developing and assessing potential caribou recovery strategies. [ABSTRACT FROM AUTHOR]

This research uses the acoustic coda phase delay method to estimate relative changes in air temperature between explosions with varying event masses and heights of burst. It also places a bound on source–receiver distance for the method. Previous studies used events with different shapes, height of bursts, and masses and recorded the acoustic codas at source–receiver distances less than 1 km. This research further explores the method using explosions that differ in mass (by up to an order of magnitude) and are placed at varying heights. Source–receiver distances also cover an area out to 7 km. Relative air temperature change estimates are compared to complementary meteorological observations. Results show that two explosions that differ by an order of magnitude cannot be used with this method because their propagation times in the near field and their fundamental frequencies are different. These differences are expressed as inaccuracies in the relative air temperature change estimates. An order of magnitude difference in mass is also shown to bias estimates higher. Small differences in height of burst do not affect the accuracy of the method. An upper bound of 1 km on source–receiver distance is provided based on the standard deviation characteristics of the estimates. [ABSTRACT FROM AUTHOR]

Habitat alteration and climate change are two important environmental stressors posing increasing threats to woodland caribou, Rangifer tarandus caribou, in Ontario. Our first objective was to identify the importance of linear features, habitat, and climate on the occurrence of woodland caribou during the winter season using over 30 years of records (1980-2012). Our second objective was to forecast the impacts of climate change on the future occurrence and range of woodland caribou. Woodland caribou occurrence and environmental data collected during 1980 to 2012 were obtained from the Ontario Ministry of Natural Resources (OMNR). Logistic regression models were used to identify the importance of linear features, habitat, and climate on woodland caribou. We then forecast future caribou occurrences using 126 future climate projections. Woodland caribou preferred coniferous forests and mixed forests that tended to be associated with increased lichen coverage, and regions with colder winters. Woodland caribou also avoided anthropogenically disturbed regions, such as areas associated with high road density or developed areas. Caribou range extent was projected to contract by 57.2-100% by 2050 and 58.9-100% by 2070. Furthermore, all 126 climate change scenarios forecast a range loss of at least 55% for woodland caribou in Ontario by 2050. We project complete loss of woodland caribou in Ontario if winter temperatures increase by more than 5.6°C by 2070. We found that woodland caribou in Ontario are sensitive to changes in climate and forecasted that an average of 95% of Ontario's native woodland caribou could become extirpated by 2070. The greatest extirpations were projected to occur in the northernmost regions of Ontario as well as northeastern Ontario, while regions in western Ontario were projected to have the lowest rates of extirpation. This underscores the importance of mitigating greenhouse gases as a means to protect this iconic species. [ABSTRACT FROM AUTHOR]

Variation in predation can have important consequences for predators and prey, but little is known about associated mechanisms. Diel interactions between predators and prey are commonly assumed to be influenced by movement speeds of both predators and prey individuals, sensu the ideal gas model, but the influencing factors of diel predation dynamics have yet to be empirically examined., In this study, we apply principles of the ideal gas model to predict diel variation in kill frequency of moose ( Alces alces) by wolves ( Canis lupus) in northern Ontario, Canada based on GPS radio-telemetry data combined with field verification of kills., We used GPS telemetry data from wolves and moose combined with a unique data set on the diel pattern of wolf kills to test whether predator movement rate, prey movement rate, and ambient light condition influence diel variation in kill rates of wolves on moose., Our results indicate that the kill rate between wolves and moose was principally related to the effective movement rate of predators and prey, as predicted by the ideal gas model. We found little evidence that light conditions had any effect on kill rates, but rather the majority of kill rate variation corresponded to wolf movement rate, which was over an order of magnitude higher than that of moose. [ABSTRACT FROM AUTHOR]

Understanding the impacts of disturbance on individual fitness is important for wildlife management, and critical for the conservation of species at risk. We compared the fitness and seasonal range use of 39 woodland caribou in Ontario study areas contrasted by their level of human disturbance. We previously showed that wolf density in the disturbed site was higher, likely due to human-modified landscapes favoring moose, the primary prey of wolves. In this paper we address three objectives. First, because the assimilation of dietary nitrogen is heavily influenced by metabolic processes related to stress, we hypothesized that ratios of nitrogen isotopes ( δ 15 N) may indicate changes in body condition in ungulates and be useful proxies for changes in fitness. Second, we predicted that increased predation risk from wolves in disturbed areas would result in measurable declines in caribou body condition. Third, we hypothesized that one mechanism for fitness declines among caribou in the disturbed area was increased wolf activity restricting caribou seasonal movements. We showed change in δ 15 N in the tissues of caribou was correlated with body condition scoring using fat assessment. We used GPS collars to quantify seasonal range use and found that fitness was higher, and seasonal range overlap was lower, in caribou using the nondisturbed area. Winter fitness declines were significantly larger in the more disturbed area. Our study identifies another mechanism by which the cumulative effects of human-disturbed landscapes on caribou fitness could contribute to global declines in caribou populations. [ABSTRACT FROM AUTHOR]

The distribution and abundance of woodland caribou (Rangifer tarandus caribou) have declined dramatically in the past century. Without intervention the most southern population of caribou in eastern North America is expected to disappear within 20 years. Although translocations have reintroduced and reinforced some populations, approximately half of caribou translocation efforts fail. Translocations are resource intensive and risky, and multiple interrelated factors must be considered to assess their potential for success. Structured decision-making tools, such as Bayesian belief networks, provide objective methods to assess different wildlife management scenarios by identifying the key components and relationships in an ecosystem. They can also catalyze dialogue with stakeholders and provide a record of the complex thought processes used in reaching a decision. We developed a Bayesian belief network for a proposed translocation of woodland caribou into a national park on the northeastern coast of Lake Superior, Ontario, Canada. We tested scenarios with favourable (e.g., good physical condition of adult caribou) and unfavourable (e.g., high predator densities) conditions with low, medium, and high numbers of translocated caribou. Under the current conditions at Pukaskwa National Park, augmenting the caribou population is unlikely to recover the species unless wolf densities remain low (<5.5/1000 km2) or if more than 300 animals could be translocated. [ABSTRACT FROM AUTHOR]

One of the most challenging tasks in wildlife conservation and management is to clarify how spatial variation in land cover due to anthropogenic disturbance influences wildlife demography and long‐term viability. To evaluate this, we compared rates of survival and population growth by woodland caribou (Rangifer tarandus caribou) from 2 study sites in northern Ontario, Canada that differed in the degree of anthropogenic disturbance because of commercial logging and road development, resulting in differences in predation risk due to gray wolves (Canis lupus). We used an individual‐based model for population viability analysis (PVA) that incorporated adaptive patterns of caribou movement in relation to predation risk and food availability to predict stochastic variation in rates of caribou survival. Field estimates of annual survival rates for adult female caribou in the unlogged (x¯= 0.90) and logged (x¯= 0.76) study sites recorded during 2010–2014 did not differ significantly (P > 0.05) from values predicted by the individual‐based PVA model (unlogged: x¯ = 0.87; logged: x¯= 0.79). Outcomes from the individual‐based PVA model and a simpler stage‐structured matrix model suggest that substantial differences in adult survival largely due to wolf predation are likely to lead to long‐term decline of woodland caribou in the commercially logged landscape, whereas the unlogged landscape should be considerably more capable of sustaining caribou. Estimates of population growth rates (λ) for the 2010–2014 period differed little between the matrix model and the individual‐based PVA model for the unlogged (matrix model x¯ = 1.01; individual‐based model x¯ = 0.98) and logged landscape (matrix model x¯ = 0.88; individual‐based model x¯ = 0.89). We applied the spatially explicit PVA model to assess the viability of woodland caribou across 14 woodland caribou ranges in Ontario. Outcomes of these simulations suggest that woodland caribou ranges that have experienced significant levels of commercial forestry activities in the past had annual growth rates <0.89, whereas caribou ranges that had not experienced commercial forestry operations had population growth rates >0.96. These differences were strongly related to regional variation in wolf densities. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We used matrix and individual‐based population viability assessment models to compare the demography of woodland caribou populations in Ontario in unlogged landscapes with those in logged landscapes. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. [ABSTRACT FROM AUTHOR]

Use of camera traps for non-invasive data collection is increasingly common in wildlife studies. This technique presents a valuable, but generally unexploited, opportunity to learn about carnivore diet through direct observations of predators with prey. To highlight this potential, we present a collection of photographic observations from Michipicoten Island, ON, Canada, that improve our knowledge of the diets of northern carnivores. These include the first documentation of Vulpes vulpes (Red Fox) consumption of a Colaptes auratus (Northern Flicker) and the first photographic evidence of wintertime consumption of a Lithobates sp. (frog) by a Mustela erminea (Short-tailed Weasel). We discuss the implications of these observations and the use of camera traps to gather data on carnivore diets, including caveats to this technique. [ABSTRACT FROM AUTHOR]

Abstract: The ideal free distribution assumes that animals select habitats that are beneficial to their fitness. When the needs of dependent offspring differ from those of the parent, ideal habitat selection patterns could vary with the presence or absence of offspring. We test whether habitat selection depends on reproductive state due to top‐down or bottom‐up influences on the fitness of woodland caribou (Rangifer tarandus caribou), a threatened, wide‐ranging herbivore. We combined established methods of fitting resource and step selection functions derived from locations of collared animals in Ontario with newer techniques, including identifying calf status from video collar footage and seasonal habitat selection analysis through latent selection difference functions. We found that females with calves avoided predation risk and proximity to roads more strongly than females without calves within their seasonal ranges. At the local scale, females with calves avoided predation more strongly than females without calves. Females with calves increased predation avoidance but not selection for food availability upon calving, whereas females without calves increased selection for food availability across the same season. These behavioral responses suggest that habitat selection by woodland caribou is influenced by reproductive state, such that females with calves at heel use habitat selection to offset the increased vulnerability of their offspring to predation risk. [ABSTRACT FROM AUTHOR]

ABSTRACT: Habitat loss has been implicated in the decline of forest‐dwelling caribou (Rangifer tarandus caribou), but it is unknown how biting insects, potentially important components of boreal forest habitat for caribou, influence the activity of this threatened species. During summers in 2011 and 2012 in northern Ontario, Canada, we quantified the relative abundance of black flies, mosquitoes, and tabanids in boreal forest stands of different ages and related their abundance to caribou activity. We counted insects in young (25–35 yrs since forest harvesting), intermediate (36–69 yrs), and old (≥70 yrs) stands using sweep nets and counts on human subjects. We related the daily variation in abundance of these insect families, along with daily maximum temperature, to the activity of female caribou, determined by accelerometers in global positioning system collars. We found higher insect abundance in young versus old stands. During the first 5 minutes in a forest stand, the rate of accumulation of mosquitoes and black flies on human subjects increased, but at a decelerating rate, whereas tabanid abundance declined over time. On days when tabanids were more numerous, female caribou were less active, possibly a response to reduce exposure and harassment. To a lesser extent, mosquitoes and black flies also tended to elicit lower activity of caribou. Our study reveals that biting flies can alter the behavior of female caribou in the boreal forest. Loss of old stands may accentuate the potential for insect harassment. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Woodland caribou (Rangifer tarandus caribou) in Ontario are a threatened species that have experienced a substantial retraction of their historic range. Part of their decline has been attributed to increasing densities of anthropogenic linear features such as trails, roads, railways, and hydro lines. These features have been shown to increase the search efficiency and kill rate of wolves. However, it is unclear whether selection for anthropogenic linear features is additive or compensatory to selection for natural (water) linear features which may also be used for travel. We studied the selection of water and anthropogenic linear features by 52 resident wolves (Canis lupus x lycaon) over four years across three study areas in northern Ontario that varied in degrees of forestry activity and human disturbance. We used Euclidean distance-based resource selection functions (mixed-effects logistic regression) at the seasonal range scale with random coefficients for distance to water linear features, primary/secondary roads/railways, and hydro lines, and tertiary roads to estimate the strength of selection for each linear feature and for several habitat types, while accounting for availability of each feature. Next, we investigated the trade-off between selection for anthropogenic and water linear features. Wolves selected both anthropogenic and water linear features; selection for anthropogenic features was stronger than for water during the rendezvous season. Selection for anthropogenic linear features increased with increasing density of these features on the landscape, while selection for natural linear features declined, indicating compensatory selection of anthropogenic linear features. These results have implications for woodland caribou conservation. Prey encounter rates between wolves and caribou seem to be strongly influenced by increasing linear feature densities. This behavioral mechanism–a compensatory functional response to anthropogenic linear feature density resulting in decreased use of natural travel corridors–has negative consequences for the viability of woodland caribou. [ABSTRACT FROM AUTHOR]

Site-specific variation in relative habitat abundance and disturbance regimes may produce differences in habitat preferences of associated populations. An evaluation of the predictive power of habitat selection models across space would benefit our understanding of the reliability of models of selection and space use in predicting animal occurrence. We used presence-absence data from winter surveys of moose ( Alces alces (L., 1758)) to estimate resource selection functions (RSFs) across two study sites using Far North Land Cover updated with recent disturbance from fire and timber harvest. Moose selected foraging habitat (e.g., deciduous land cover) and for increasing deciduous foliage cover (ΔNDVI, i.e., the difference in the normalized difference vegetation index). Snow depth negatively influenced habitat selection, likely due to increased predation risk and reduced movement and foraging efficiency. Models lost little predictive power when applied to another site based on comparison of receiver operating characteristic (ROC) curves. Our results corroborated the current body of knowledge concerning moose habitat selection, i.e., moose preferentially use forest stands dominated by deciduous species, but suggested that moose strongly avoided very recently disturbed areas. Minimal site-specific variation and ROC comparison suggests that RSFs may be extended into novel systems, given adequate consideration for habitat quality and abundance, thereby simplifying management needs of this important species. [ABSTRACT FROM AUTHOR]

Although local variation in territorial predator density is often correlated with habitat quality, the causal mechanism underlying this frequently observed association is poorly understood and could stem from facultative adjustment in either group size or territory size., To test between these alternative hypotheses, we used a novel statistical framework to construct a winter population-level utilization distribution for wolves ( Canis lupus) in northern Ontario, which we then linked to a suite of environmental variables to determine factors influencing wolf space use. Next, we compared habitat quality metrics emerging from this analysis as well as an independent measure of prey abundance, with pack size and territory size to investigate which hypothesis was most supported by the data., We show that wolf space use patterns were concentrated near deciduous, mixed deciduous/coniferous and disturbed forest stands favoured by moose ( Alces alces), the predominant prey species in the diet of wolves in northern Ontario, and in proximity to linear corridors, including shorelines and road networks remaining from commercial forestry activities., We then demonstrate that landscape metrics of wolf habitat quality - projected wolf use, probability of moose occupancy and proportion of preferred land cover classes - were inversely related to territory size but unrelated to pack size., These results suggest that wolves in boreal ecosystems alter territory size, but not pack size, in response to local variation in habitat quality. This could be an adaptive strategy to balance trade-offs between territorial defence costs and energetic gains due to resource acquisition. That pack size was not responsive to habitat quality suggests that variation in group size is influenced by other factors such as intraspecific competition between wolf packs. [ABSTRACT FROM AUTHOR]

We used remote video cameras to assess seasonal diet composition of woodland caribou ( Rangifer tarandus tarandus (L., 1758)) at three areas across the boreal forest of Ontario. Caribou consume lichens in winter, but we expected they would significantly reduce lichen consumption in favour of higher protein levels in green plants in summer. We sampled videos from 23 caribou, from 2 years, to derive seasonal diet composition. Diet differed among seasons and study areas, except in winter when lichens dominated. Diet breadth doubled from winter to summer, but overlap between seasons was still >60%. Green plants were less commonly eaten than we expected, only three genera were preferred, and few species constituted more than 2% of the diet. Preferred foods varied by land-cover types. Diet differed between managed and unmanaged landscapes but did not result from use of plant species found in successional habitats. Caribou selected a nonoptimal diet in the snow-free seasons, especially with respect to protein, suggesting factors other than nutrition influenced diet choice, and indicating the possibility of bottom-up limitation on production. [ABSTRACT FROM AUTHOR]

The diet of woodland caribou ( Rangifer tarandus caribou Gmelin, 1788) in the boreal zone of North America is poorly understood. In large part this is because they occur at low densities in environments that are difficult to access. The only method available for identifying food requirements of wildlife has been histological examination of fecal samples, a technique that suffers from a number of serious limitations. Our study used fecal samples from 125 woodland caribou and animal-borne videos to address two questions: (1) How do the new technologies, video cameras and DNA barcoding, compare with conventional diet analyses of fecal pellets? and (2) Can these techniques be used to determine the diet of woodland caribou? Our results show that microhistology estimates provide an inaccurate approximation of diet; <15% correlation with either barcoding or video techniques. Taxonomic resolution of the histology estimates was very low. Taxonomic resolution to species found in fecal samples was good using video (42%) but better using DNA barcoding (94%). DNA barcoding and video technologies provided dietary data that were highly correlated (70%) among major groups of plants, with terrestrial lichens dominating the late winter through early spring diet. The high species resolution of DNA barcoding may be supplemented by information on habitat preference and degree of feeding selectivity obtained by video surveillance. These novel technologies may be important tools for identifying critical habitat requirements and associated conservation strategies needed for elusive wildlife species that are endangered. [ABSTRACT FROM AUTHOR]

We present a broad-band tomographic model of Lg attenuation in the Middle East derived from source- and site-corrected amplitudes. Absolute amplitude measurements are made on hand-selected and carefully windowed seismograms for tens of stations and thousands of crustal earthquakes resulting in excellent coverage of the region. A conjugate gradient method is used to tomographically invert the amplitude data set of over 8000 paths over a 45°× 40° region of the Middle East. We solve for Q variation, as well as site and source terms, for a wide range of frequencies ranging from 0.5 to 10 Hz. We have modified the standard attenuation tomography technique to more explicitly define the earthquake source expression in terms of the seismic moment. This facilitates the use of the model to predict the expected amplitudes of new events, an important consideration for earthquake hazard or explosion monitoring applications. The attenuation results have a strong correlation to tectonics. Shields have low attenuation, whereas tectonic regions have high attenuation, with the highest attenuation at 1 Hz found in eastern Turkey. The results also compare favourably to other studies in the region made using Lg propagation efficiency, Lg/ Pg amplitude ratios and two-station methods. We tomographically invert the amplitude measurements for each frequency independently. In doing so, it appears the frequency dependence of attenuation in all regions is not compatible with the power-law representation of Q( f ), an assumption that is often made. [ABSTRACT FROM AUTHOR]

We report the crustal structure for two locations in Iraq estimated by joint inversion of P-wave receiver functions (RFs) and surface (Rayleigh) wave group velocity dispersion. RFs were computed from teleseismic recordings at two temporary broad-band seismic stations located in Mosul (MSL) in the Zagros Fold Belt and Baghdad (BHD) in the Mesopotamian Foredeep. Group velocity dispersion curves at the sites were derived from continental-scale tomography. The inversion results show that the crustal thicknesses are 39 km at MSL and 43 km at BHD. We observe a strong PsMoho at BHD consistent with a sharp Moho discontinuity. However, at MSL we observe a weak PsMoho suggesting a transitional Moho where crustal thickening is likely to be occurring in the deep crust. Both sites reveal low velocity surface layers consistent with sedimentary thickness of about 3 km at station MSL and 7 km at BHD and agreeing well with the previous reports. Ignoring the sediments, the crystalline crustal velocities and thicknesses are remarkably similar at both stations. The similarity of crustal structure suggests that the crust of the northeastern proto-Arabian Platform was uniform before subsidence and deposition of the sediments in the Cenozoic. If crystalline crustal structure is uniform across the northern Arabian Platform then crustal thickness variations in the Zagros Fold Belt and Thrust Zone should reveal the history of deformation and crustal shortening in the Arabian–Eurasian collision zone and not reflect pre-existing crustal thickness variations in the Arabian Plate. [ABSTRACT FROM AUTHOR]

We have used data from the Kuwait National Seismic Network (KNSN) to estimate the seismic structure of Kuwait using a limited amount of seismic data. First, we made surface wave dispersion measurements and calculated receiver functions from the relatively small amount of data available from the broad-band station, KBD. Models were derived from the joint inversion of teleseismic receiver functions and Rayleigh and Love fundamental mode surface wave group velocity dispersion. While both surface waves and receiver functions by themselves can be used to estimate lithospheric structure, we have successfully combined the two to reduce non-uniqueness in estimates based on the individual data sets. The resulting KUW1 model features a thick (8 km) sedimentary cover and crustal thickness of 45 km. Crustal velocities below the sedimentary cover are consistent with global averages for stable platforms. We infer upper-mantle velocities (7.84 km s–1 P-wave velocity; 4.40 km s–1 S-wave velocity) that are slightly lower than expected for a stable platform. In comparison with other crustal structure estimates for the Arabian platform to the west, the crust is thicker and the mantle is slower in Kuwait. This is consistent with the overall tectonic trends of the region that find increasing crustal thickness between the divergent plate boundary at the Red Sea and the convergent plate boundary at the Zagros Mts, as well as slow mantle velocities beneath this nearby orogenic zone. The resulting model fits the traveltimes of regional phases (Pn, Pg, Sn and Lg). Independent inversion of local earthquake traveltimes recorded by KNSN (allowing for event hypocentre relocation) results in a remarkably similar velocity structure, providing confidence that the joint inversion of receiver functions and surface wave group velocities can impose accurate constraints on crustal structure for local event location and network operations. Relocation of events in Kuwait improves the clustering of events and results in shallower hypocentres. [ABSTRACT FROM AUTHOR]

The decline of woodland caribou (Rangifer tarandus caribou) has been attributed to anthropogenic landscape disturbances, but critical distance thresholds and time lags between disturbance and extirpation are unknown. Using a database of caribou presence and extirpation for northern Ontario, Canada, geo-coded to 10 X 10-km cells, we constructed logistic regression models to predict caribou extirpation based on distance to the nearest of each of 9 disturbance types: forest cutovers, fires, roads, utility corridors, mines, pits and quarries, lakes, trails, and rail lines. We used Akaike's Information Criterion to select parsimonious models and Receiver-Operating Characteristic curves to derive optimal thresholds. To deal with the effects of spatial autocorrelation on estimates of model significance, we used subsampling and restricted randomizations. Forest cutovers were the best predictor of caribou occupancy, with a tolerance threshold of 13 km to nearest cutover and a time lag of 2 decades between disturbance by cutting and caribou extirpation. Management of woodland caribou should incorporate buffers around habitat and requires long-term monitoring of range occupancy. [ABSTRACT FROM AUTHOR]

Abstract: Seismic anisotropy, a property linked to the texture of the mantle rock, should be distributed with depth along the trace of the Dead Sea Rift (DSR), owing to a combination of present day and ancient tectonics. Using data from four permanent and one temporary seismic observatories we evaluate birefringence (splitting) of 91 teleseismic core-refracted shear waves, primarily SKS phases. We find significant levels of birefringence in the bulk of observed phases. We also find that birefringence parameters (fast directions and delays) vary as a function of source–receiver geometry. Notably, the pattern of this directional variation in birefringence is quite similar at all sites we have examined. We interpret observed birefringence in SKS phases in terms of one- and two-layer models. Single-layer models for all stations exhibit a fast polarization oriented 12–19° east of north, with anisotropy sufficient to generate 1.3-s time delay. We find strong evidence for at least two distinct anisotropic layers. For the two layer models, the upper layers resemble the single-layer models, showing near-north fast polarizations and delays on the order of 1s. Three out of four sites show fast polarizations in the lower layer that strike 50–80° CW from north with time delays 0.3–0.6s. One site, at the northern end of the DSR, displays a higher degree of anisotropy in the lower layer, and a more northerly fast polarization. Overall, the lower layers at all sites appear to be consistent with the deformation caused by plate motion relative to the asthenosphere. The fabric in the upper layer is sub-parallel to the present-day transcurrent motion on the DSR, but also matches the typical orientation of lithospheric seismic anisotropy in the Arabian shield. Our overall conclusion is that the impact of the DSR on the rock fabric of the mantle lithosphere is probably quite weak. [Copyright &y& Elsevier]

We analyzed mantle anisotropy along the Red Sea and across the Arabian Peninsula using shear-wave splitting recorded by stations from three different seismic networks—the largest, most widely distributed array of stations examined across the Arabian Peninsula to date. Stations near the Gulf of Aqaba display fast orientations aligned parallel to the Dead Sea transform fault, most likely related to the strike-slip motion between Africa and Arabia. However, most of our observations across Arabia are statistically the same (at a 95% confidence level), with north-south—oriented fast directions and delay times averaging ~1.4 s. Since end-member models of fossilized anisotropy and present-day asthenospheric flow do not adequately explain these observations, we interpret them as a combination of plate- and density-driven flow in the asthenosphere. The combination of northeast-oriented flow associated with absolute plate motion with northwest-oriented flow associated with the channelized Afar upwelling along the Red Sea produces a north-south resultant that matches the observations and supports models of active rifting. [ABSTRACT FROM AUTHOR]