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Identifier Title Type Subject
Contact networks reveal potential for interspecific interactions of sympatric wild felids driven by space useContact networks reveal potential for interspecific interactions of sympatric wild felids driven by space useArticleBobcat
Competition
Development
Exurban
<em>Felis rufus</em>
Mountain lion
Networks
<em>Puma concolor</em>
Urbanization
Wildland–urban interface
Type:Article
Subject:Bobcat
Competition
Development
Exurban
<em>Felis rufus</em>
Mountain lion
Networks
<em>Puma concolor</em>
Urbanization
Wildland–urban interface
Description:Competitive interactions between species are fundamental to understanding species assemblages, community dynamics, and ecological processes. Anthropogenic landscape change, particularly resulting from urbanization, can alter interspecific interactions; however, different forms of urbanization are predicted to have contrasting effects on competitive interactions. We developed contact networks between bobcats and pumas to evaluate (1) the potential for interspecific interactions between wild felids and (2) how space-use metrics might change along the urban gradient, including low-density exurban development, wildland–urban interface, and wildland habitat, at both the population and individual level. We used an extensive telemetry data set for bobcats and pumas across multiple study areas to evaluate four space-use metrics: space-use overlap (used to define potential interactions among animals) and three additional contact network metrics, including degree (the number of potentially interacting animals), in-strength (sum of space-use overlap for animals), and equivalent social connectivity (ESC; considering both space-use extent and the amount of space-use overlap). Space-use extent was an important predictor of potential social interactions as measured by space-use metrics. Bobcats appeared to have a greater opportunity to interact with female pumas based on space-use overlap, degree, and in-strength, which demonstrates that relative scale of space-use extent among animals could be important for understanding interactions; ESC, however, was greater between bobcats and male pumas, likely due to the larger space-use extent by male compared to female pumas and the positive relationship between space-use extent and ESC. In addition, pumas and male bobcats exhibited a greater opportunity to interact, based on space-use overlap, degree, and in-strength, and demonstrated higher ESC compared to female bobcats. Counter to our predictions, felids associated with urbanized grids or with greater amounts of urbanization in their extent of space use did not appear to exhibit greater values of space-use metrics compared to animals with less exposure to urbanization; these results appear consistent with previous research evaluating population characteristics of felids across broad scales in our study areas. Greater ESC for male pumas and male bobcats suggests that males could be particularly important for facilitating connectivity of some ecological processes, such as the transmission of disease, through interspecific contact networks. [show more]
Continuous-time discrete-space models for animal movementContinuous-time discrete-space models for animal movementArticleAnimal movement
Multiple imputation
Varying-coefficient model
Markov chain
Type:Article
Subject:Animal movement
Multiple imputation
Varying-coefficient model
Markov chain
Description:The processes influencing animal movement and resource selection are complex and varied. Past efforts to model behavioral changes over time used Bayesian statistical models with variable parameter space, such as reversible-jump Markov chain Monte Carlo approaches, which are computationally demanding and inaccessible to many practitioners. We present a continuous-time discrete-space (CTDS) model of animal movement that can be fit using standard generalized linear modeling (GLM) methods. This CTDS approach allows for the joint modeling of location-based as well as directional drivers of movement. Changing behavior over time is modeled using a varying-coefficient framework which maintains the computational simplicity of a GLM approach, and variable selection is accomplished using a group lasso penalty. We apply our approach to a study of two mountain lions (Puma concolor) in Colorado, USA. [show more]
Cougar management in North AmericaCougar management in North AmericaArticleCougar
<em>Puma concolor</em>
Wildlife management
Conservation
Wildlife conservation
Type:Article
Subject:Cougar
<em>Puma concolor</em>
Wildlife management
Conservation
Wildlife conservation
Description:

The cougar is one of the most beautiful, enigmatic, and majestic animals in the Americas. Eliciting reverence for its grace and independent nature, it also triggers fear when it comes into contact with people, pets, and livestock or competes for hunters’ game. Mystery, myth, and misunderstanding surround this remarkable creature.

The cougar’s range once extended from northern Canada to the tip of South America, and from the Pacific to the Atlantic, making it the most widespread animal in the western hemisphere. But overhunting and loss of habitat vastly reduced cougar numbers by the early twentieth century across much of its historical range, and today the cougar faces numerous threats as burgeoning human development encroaches on its remaining habitat.

When Maurice Hornocker began the first long-term study of cougars in the Idaho wilderness in 1964, little was known about this large cat. Its secretive nature and rarity in the landscape made it difficult to study. But his groundbreaking research yielded major insights and was the prelude to further research on this controversial species.

The capstone to Hornocker’s long career studying big cats, Cougar is a powerful and practical resource for scientists, conservationists, and anyone with an interest in large carnivores.  He and conservationist Sharon Negri bring together the diverse perspectives of twenty-two distinguished scientists to provide the fullest account of the cougar’s ecology, behavior, and genetics, its role as a top predator, and its conservation needs. This compilation of recent findings, stunning photographs, and firsthand accounts of field research unravels the mysteries of this magnificent animal and emphasizes its importance in healthy ecosystem processes and in our lives.

[show more]
Cougars are recolonizing the midwest: analysis of cougar confirmations during 1990–2008Cougars are recolonizing the midwest: analysis of cougar confirmations during 1990–2008ArticleCougar
Midwest
<em>Puma concolor</em>
Recolonization
Type:Article
Subject:Cougar
Midwest
<em>Puma concolor</em>
Recolonization
Description:Although cougars (Puma concolor) were extirpated from much of midwestern North America around 1900, hard evidence of cougar presence has increased and populations have become established in the upper portions of the Midwest during the past 20 years. Recent occurrences of cougars in the Midwest are likely due to dispersal of subadult cougars into the region from established western populations, and may be indicative of further recolonization and range expansion. We compiled confirmed locations of cougars (i.e., via carcasses, tracks, photos, video, and DNA evidence) collected during 1990–2008 in 14 states and provinces of midwestern North America. We separated our study area into 2 regions (east and west), calculated number and types of confirmations, and assessed trends in confirmations during the study period. We recorded 178 cougar confirmations in the Midwest and the number of confirmations increased during the study period (r = 0.79, P ≤ 0.001). Confirmations by state or province ranged from 1 (Kansas, Michigan, and Ontario) to 67 (Nebraska). Carcasses were the most prevalent confirmation type (n = 56). Seventy-six percent of known-sex carcass confirmations were males, consistent with predominantly male-biased dispersal in cougars. More confirmations (P = 0.05) were recorded in the western region  than the eastern region . Seventy-nine percent of cougar confirmations occurred within 50 km of highly suitable habitat (i.e., forest areas with steep terrain and low road and human densities). Given the number of cougar confirmations, the increasing frequency of occurrences, and that long-distance dispersal has been documented via radiocollared individuals, our research suggests that cougars are continuing to recolonize midwestern North America. [show more]
Cougars on the edgeCougars on the edgeArticleCougars
Human-animal relationships
Populations
Boulder, Colorado
Type:Article
Subject:Cougars
Human-animal relationships
Populations
Boulder, Colorado
Description:Cougars once occupied a range in the Western Hemisphere larger than that of any terrestrial mammal (other than humans) since the Pleistocene (Rabinowitz 2010). Highly adaptable, cougars inhabited deserts, grasslands, tropical rainforests, temperate mountains, and boreal forests. After Europeans settled North America, however, they virtually eliminated eastern cougar populations and dramatically reduced western populations in an effort to protect livestock and valued game species, and also to protect themselves. Later, government funded control and bounty programs, along with widespread unregulated killing of predators in the late 1800s and early 1900s, contributed to further cougar population declines. [show more]
CPW Photo Warehouse: a custom database to facilitate archiving, identifying, summarizing and managing photo data collected from camera trapsCPW Photo Warehouse: a custom database to facilitate archiving, identifying, summarizing and managing photo data collected from camera trapsArticleCamera traps
Database
Multiple observers
Photos
Wildlife cameras
Type:Article
Subject:Camera traps
Database
Multiple observers
Photos
Wildlife cameras
Description:

Summary

  1. Contemporary methods for sampling wildlife populations include the use of remotely triggered wildlife cameras (i.e., camera traps). Such methods often result in the collection of hundreds of thousands of photos that must be identified, archived, and transformed into data formats required for statistical analyses.
  2. Cpw Photo Warehouse is a freely available software based in Microsoft Access® that has been customized for this purpose using Visual Basic® for Applications (VBA) code. Users navigate a series of point-and-click menu items that allow them to input information from camera deployments, automatically import photos (and image data stored within the photos) related to those deployments, and store data within a relational database. Images are seamlessly incorporated into the database windows, but are stored separately from the database.
  3. The database includes menu options that (i) facilitate identification of species within the images, (ii) allow users to view and filter any subset of the databased on study area, species, season, etc., and (iii) produce input files for common analyses such as occupancy, abundance, density and activity patterns using Programs mark, presence, density and the r packages ‘secr’ and ‘overlap’.
  4. Our database makes explicit use of multiple observers, which greatly enhances the efficiency and accuracy with which a large number of photos can be identified. Modular subsets of the data can be distributed to an unlimited number of observers on or off site for identification. Modules are then re-incorporated into the database using a custom import function.
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Cultivars of popular restoration grass developed for drought do not have higher drought resistance and do not differ in drought-related traits from other accessionsCultivars of popular restoration grass developed for drought do not have higher drought resistance and do not differ in drought-related traits from other accessionsArticleCultivars
Drought strategies
Functional traits
Intraspecific trait variation
Ontogeny
Root traits
Type:Article
Subject:Cultivars
Drought strategies
Functional traits
Intraspecific trait variation
Ontogeny
Root traits
Description:Numerous functional traits have been identified as key contributors to plant performance under drought. However, many of these traits, specifically root traits, are rarely considered in the development of native plant cultivars. In this study, we assessed whether cultivars of the perennial grass Elymus trachycaulus (Slender wheatgrass) developed for drought differ in (a) drought resistance (i.e. a plant's ability to maintain aboveground biomass productivity under water deficit), (b) aboveground and belowground traits, and (c) trait responses to drought from other accessions (i.e. other cultivars, wild accessions). We also evaluated trait plasticity, assessed whether multivariate trait relationships varied between control and drought conditions, and determined which suites of traits are related to drought resistance. We worked with seedlings at two developmental stages to assess whether patterns vary ontogenetically. E. trachycaulus cultivars developed for drought did not differ from other accessions in drought resistance or traits related to drought-coping strategies. The effects of drought and accession on drought resistance, traits, and trait plasticity varied by developmental stage, but relationships among traits varied little between the two developmental stages. A primary axis of functional variation related to resource acquisition (plant height, root length, root tips) was consistently associated with drought resistance. However, which secondary axes were related to drought resistance varied by developmental stage and moisture condition. Our results suggest that traits and performance of commonly used cultivars ought to be reexamined to determine whether they are actually the best candidates for revegetation projects in specific contexts. [show more]
Demography, education, and research trends in the
interdisciplinary field of disease ecology
Demography, education, and research trends in the
interdisciplinary field of disease ecology
ArticleHost-pathogen interaction
Infectious disease
Machine learning
Type:Article
Subject:Host-pathogen interaction
Infectious disease
Machine learning
Description:Micro-and macroparasites are a leading cause of mortality for humans, animals, and plants, and there is great need to understand their origins, transmission dynamics, and impacts. Disease ecology formed as an interdisciplinary field in the 1970s to fill this need and has recently rapidly grown in size and influence. Because interdisciplinary fields integrate diverse scientific expertise and training experiences, understanding their composition and research priorities is often difficult. Here, for the first time, we quantify the composition and educational experiences of a subset of disease ecology practitioners and identify topical trends in published research. We combined a large survey of self-declared disease ecologists with a literature synthesis involving machine-learning topic detection of over 18,500 disease ecology research articles. The number of graduate degrees earned by disease ecology practitioners has grown dramatically since the early 2000s. Similar to other science fields, we show that practitioners in disease ecology have diversified in the last decade in terms of gender identity and institution, with weaker diversification in race and ethnicity. Topic detection analysis revealed how the frequency of publications on certain topics has declined (e.g., HIV, serology), increased (e.g., the dilution effect, infectious disease in bats), remained relatively common (e.g., malaria ecology, influenza, vaccine research and development), or have consistently remained relatively infrequent (e.g., theoretical models, field experiments). Other topics, such as climate change, superspreading, emerging infectious diseases, and network analyses, have recently come to prominence. This study helps identify the major themes of disease ecology and demonstrates how publication frequency corresponds to emergent health and environmental threats. More broadly, our approach provides a framework to examine the composition and publication trends of other major research fields that cross traditional disciplinary boundaries. [show more]
Density and demography of snowshoe hares in central ColoradoDensity and demography of snowshoe hares in central ColoradoArticleColorado
Demography
Density
Forest management
<em>Lepus americanus</em>
Recruitment
Snowshoe hare
Survival
Telemetry
Type:Article
Subject:Colorado
Demography
Density
Forest management
<em>Lepus americanus</em>
Recruitment
Snowshoe hare
Survival
Telemetry
Description:To improve understanding of snowshoe hare ecology in the Southern Rockies and enhance the ability of agency personnel to manage subalpine landscapes for snowshoe hares (Lepus americanus) and lynx (Lynx canadensis) in the region, we estimated snowshoe hare density, survival, and recruitment in west-central Colorado, USA from July 2006–March 2009. We sampled 3 types of forest stands that purportedly provide good habitat for hares: 1) mature Engelmann spruce (Picea engelmannii)–subalpine fir (Abies lasiocarpa), 2) early seral, even-aged lodgepole pine (Pinus contorta), and 3) mid-seral, even-aged lodgepole pine that had been pre-commercially thinned. In all forest types and all seasons, snowshoe hare densities were <1.0 hares/ha. During summer, hare densities [±SE] were highest in early seral lodgepole pine (0.20 [0.01] to 0.66 [0.07] hares/ha), lowest in mid-seral lodgepole pine (0.01 [0.04] to 0.03 [0.03] hares/ha), and intermediate in mature spruce-fir (0.01 [0.002] to 0.26 [0.08] hares/ha). During winter, densities were more similar among the 3 stand types. Annual survival of hares was highest in mature spruce-fir (0.14 [0.05] to 0.20 [0.07]) and similar between the 2 lodgepole stand types (0.10 [0.03] to 0.16 [0.06]). Stand attributes indicative of dense cover were positively correlated with density estimates and explained relatively more spatial process variance in hare densities than other attributes. These same attributes were not positively correlated with hare survival. Both density and survival of hares in early seral lodgepole stands were positively correlated with the extent of similar stands in the surrounding landscape. Recruitment of juvenile hares occurred during all 3 summers in early seral lodgepole stands, 2 of 3 summers in mature spruce-fir stands, and in only 1 of 3 summers in mid-seral lodgepole. Based on estimates of density and demography specific to each forest type, we conclude that managers should maintain mature spruce-fir and early seral lodgepole stand types rather than thinned, mid-seral lodgepole stands to benefit snowshoe hares (and by association lynx) in central Colorado. Given the more persistent nature of spruce-fir compared to early seral lodgepole, and the fact that such stands cover considerably more area, mature spruce-fir may be the most valuable forest type for snowshoe hares in the region. [show more]
Density dependence in mule deer: A review of evidenceDensity dependence in mule deer: A review of evidenceArticleWildlife managers
Density dependence
<em>Odocoileus hemionus</em>
Colorado
Mule deer
Winter range habitat
Type:Article
Subject:Wildlife managers
Density dependence
<em>Odocoileus hemionus</em>
Colorado
Mule deer
Winter range habitat
Description:Wildlife managers often need tangible evidence of density dependence in populations to support decision making. Field experimentation to identify density dependent effects is often cost and time prohibitive. Thus, assimilation of existing knowledge into a balance of probabilities can serve as a surrogate for experimental research. A case study of such a process is found in the mule deer Odocoileus hemionus herds of Colorado. Wildlife managers and hunters expressed concern over a recent decline in western Colorado mule deer herds, yet the underlying cause of this decline is yet to be determined. In response to this management concern, we conducted a review of scientific evidence on Colorado's mule deer population dynamics. This review was done in the context of a conceptual model that portrays population growth as a function of population size, per capita growth rate and population carrying capacity. Similar declines that occurred during the 1960s and early 1990s resulted in similar reviews that identified research and management topics that would benefit mule deer. These topics included: harvest, predation, intraspecific competition, disease, interspecific competition, and habitat loss and degradation. Between the late 1990s and present time, many of these topics were addressed by research. The conventional working hypothesis in Colorado is that mule deer herds are limited by winter range habitat. We identify new gaps in knowledge and suggest potential, future research topics, as well as potential management strategies. We suggest a focus on integrated studies of multiple herbivores with density reduction experiments to address intra- and inter- specific competition. In addition, we suggest focused experiments that address the roles of mountain lion predation, black bear predation, and disease in mule deer population dynamics. [show more]