7 research outputs found

    Comparing Mexican spotted owl habitat suitability in two different habitat types using a multi-scale ensemble learning framework

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    Habitat fragmentation and loss are major threats to species conservation worldwide. Studying species-habitat relationships is a crucial first step toward understanding species habitat requirements, which is necessary for conservation and management planning. However, some species inhabit a range of habitat types, potentially making the use of range-wide habitat models inappropriate due to non-stationarity. The Mexican spotted owl (Strix occidentalis lucida) (MSO) is a species that inhabits both forests and rocky canyonlands, two habitats with large differences in environmental conditions. It is unclear whether the species uses habitat differently in these two habitat types or if previously builthabitat models for forest-dwelling owls can be used to understand where MSO use habitat in rocky canyonlands. To explore this, we developed the first scale-optimized habitat suitability model for this subspecies of spotted owl in rocky canyonlands using an ensemble framework. I then compared my results with a previously builthabitat model for MSO in forested areas. In the rocky canyonland model, slope (800 m scale), cumulative degree days (1200 m scale), insolation (1000 m scale), and monsoon precipitation (100 m scale) were the most important environmental covariates. In contrast, in the forest model, percent canopy cover (100 m scale), percent mixed-conifer (5000 m scale), and slope (500 m scale) were the most important environmental covariates. The rocky canyonland model performed well, while the forest model performed poorly and predicted low suitability across the entire study area, including areas with known nesting locations. These results confirm the non-stationarity in habitat use for MSOs between rocky canyonland and forest habitats and underscore the importance of accounting for non-stationarity across different geographic regions when modeling habitat. Hence, when transferring habitat suitability models from one region to another, it is necessary to evaluate the transferability of the model by accounting for non-stationarity

    Northern spotted owl nesting habitat under high potential wildfire threats along the California Coastal Redwood Forest

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    Large and severe wildfires, exacerbated by climate change and human behavior, are occurring more frequently in many forests across the western United States. While wildfire is a natural part of most terrestrial ecosystems, rapidly changing fire regimes have the potential to alter habitat beyond the adaptive capabilities of species. Spatial assessments of wildfire risks to species habitat may allow managers to pinpoint locations for management activities. To illustrate this, we spatially assessed wildfire risk within habitat that supports the nesting activity of the federally threatened northern spotted owl (Strix occidentalis caurina) in the California redwood coast ecoregion. To accomplish this, we built a scale-optimized ensemble nesting habitat suitability model and identified habitat with the highest wildfire hazard potential. Percent canopy cover at 100-m scale, slope at 400-m scale, and January precipitation at 800-m scale were the most influential environmental covariates for predicting northern spotted owl nesting habitat. Nearly 60% of nesting habitat was predicted to be at high or very high (>1986 index value) wildfire risks. We identified three areas in the Maple Creek Area of Humboldt County, Jackson State Demonstration Forest in Mendocino County, and Point Reyes National Seashore in Marin County, California with a high concentration of nesting habitat that are at a very high risk of experiencing high severity wildfires. We recommend these areas be targeted for future research to understand the impact of wildfire on northern spotted owl as well as management attention

    On the need for rigorous welfare and methodological reporting for the live capture of large carnivores: A response to de Araujo et al. (2021)

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    1.De Araujo et al. (Methods in Ecology and Evolution, 2021, https://doi.org/10.1111/2041-210X.13516) described the development and application of a wire foot snare trap for the capture of jaguars Panthera onca and cougars Puma concolor. Snares are a commonly used and effective means of studying large carnivores. However, the article presented insufficient information to replicate the work and inadequate consideration and description of animal welfare considerations, thereby risking the perpetuation of poor standards of reporting. 2.Appropriate animal welfare assessments are essential in studies that collect data from animals, especially those that use invasive techniques, and are key in assisting researchers to choose the most appropriate capture method. It is critical that authors detail all possible associated harms and benefits to support thorough review, including equipment composition, intervention processes, general body assessments, injuries (i.e. cause, type, severity) and post-release behaviour. We offer a detailed discussion of these shortcomings. 3.We also discuss broader but highly relevant issues, including the capture of non-target animals and the omission of key methodological details. The level of detail provided by authors should allow the method to be properly assessed and replicated, including those that improve trap selectivity and minimize or eliminate the capture of non-target animals. 4.Finally, we discuss the central role that journals must play in ensuring that published research conforms to ethical, animal welfare and reporting standards. Scientific studies are subject to ever-increasing scrutiny by peers and the public, making it more important than ever that standards are upheld and reviewed. 5. We conclude that the proposal of a new or refined method must be supported by substantial contextual discussion, a robust rationale and analyses and comprehensive documentation

    A comprehensive review on the recent development of anaerobic sludge digestions: Performance, mechanism, operational factors, and future challenges

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    After the industrial revolution, rapid population growth and burning fossil fuels led to the achievement of massive amounts of both liquid and solid waste, which can pose numerous threats for all compartments of environment. Anaerobic Digestion (AD) has been one of the most applicable techniques used during the last few decades to overcome the unpleasant presence of both organic fraction of waste and sewage sludge (SS), and as the result of this technique, biogas which is one of the main sources of energy can be produced. Therefore, the application of AD as a solution to overcome sludge and biodegradable fraction of solid waste has been the center of attentions since significant amounts of waste and sludge are being produced every day. In this regard a comprehensive review was conducted to know the advantages, disadvantages, various techniques that can improve methane yield, insights on the pretreatment methods, and operating factors was conducted to elucidate research gaps and future opportunities. Also, in the current study we discussed about operating conditions of single-stage digesters, two-stage digesters, anaerobic co-digestion. Our study is the first comprehensive review worked on the techniques by which we can improve methane yield from AD system

    Evaluation of motorists perceptions toward collision of an endangered large herbivore in Iran

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    Large herbivores possess high dispersal rates and require vast areas to roam due to their ecology. This will make them susceptible to anthropogenic threats such as vehicle-collisions. Persian onager (Equus hemionus onager), as the only representative of Artiodactyla in Iran, is not an exception. Persian onager-vehicle collision can not only be lethal for themselves but also for motorists. Given the importance of this twofold issue, an important step being taken to reduce collisions was the installation of signs that warn motorists of the high probability of onager-vehicle collisions. We developed a questionnaire to (1) assess the effectiveness of warning signs from motorists’ perspective, and (2) to identify the most important factors affecting motorist beliefs in the effectiveness of warning signs. We solicited responses to our questionnaire from motorists on a road with a high Persian onager-vehicle-collision rate in Southern Iran (Hassan Abad-Meshkan Road). To identify factors affecting motorists' beliefs in the effectiveness of warning signs we used logistic regression and for classifying motorists’ beliefs in the effectiveness of warning signs we used decision tree. Our result showed that motorists' driving speed, lack of adequate safety equipment on the road (e.g. light, police camera), using cellphone while driving, and concern about wildlife damage while driving on the road were the significant factors affecting motorists' beliefs toward the effectiveness of Persian onager warning signs. It is necessary to increase road safety equipment, install standard warning signs at the Persian onager crossing points, and study the behavior of motorists and the rate of road casualties after the mitigation methods to protect this species

    Integrating spatial analysis and questionnaire survey to better understand human-onager conflict in Southern Iran

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    Abstract Southern Iran is a conservation priority area for the endangered Persian onager (Equus hemionus onager), which is threatened by habitat fragmentation and conflict with local communities. To better understand factors that influence onager conservation, we administered a questionnaire in local communities to survey their ecological knowledge, personal experience related to onager, and attitudes toward traditional solutions for reducing crop damage by onager. In addition, we used resistant kernel and factorial least-cost path analyses to identify core areas and corridors for onager movement, and spatial randomization of vehicle collisions and crossing locations to test the predictive ability of resistant kernel and factorial least-cost path predictions of movement. We found that local communities that were knowledgeable about onagers experienced less crop damage from onager compared with those who used traditional methods. Habitat connectivity models revealed that core areas of movement are highly concentrated at the center of protected areas. Some sections of core areas have been cut off by roads where most vehicle collisions with onagers occurred. We propose that effective onager conservation will require integrated landscape-level management to reduce mortality risk, protection of core areas and corridors, development of mitigation strategies to reduce vehicle collisions, and conflict mediation between local communities and onagers

    On the need for rigorous welfare and methodological reporting for the live capture of large carnivores: A response to de Araujo et al. (2021)

    No full text
    Abstract De Araujo et al. (Methods in Ecology and Evolution, 2021, https://doi.org/10.1111/2041‐210X.13516) described the development and application of a wire foot snare trap for the capture of jaguars Panthera onca and cougars Puma concolor. Snares are a commonly used and effective means of studying large carnivores. However, the article presented insufficient information to replicate the work and inadequate consideration and description of animal welfare considerations, thereby risking the perpetuation of poor standards of reporting. Appropriate animal welfare assessments are essential in studies that collect data from animals, especially those that use invasive techniques, and are key in assisting researchers to choose the most appropriate capture method. It is critical that authors detail all possible associated harms and benefits to support thorough review, including equipment composition, intervention processes, general body assessments, injuries (i.e. cause, type, severity) and post‐release behaviour. We offer a detailed discussion of these shortcomings. We also discuss broader but highly relevant issues, including the capture of non‐target animals and the omission of key methodological details. The level of detail provided by authors should allow the method to be properly assessed and replicated, including those that improve trap selectivity and minimize or eliminate the capture of non‐target animals. Finally, we discuss the central role that journals must play in ensuring that published research conforms to ethical, animal welfare and reporting standards. Scientific studies are subject to ever‐increasing scrutiny by peers and the public, making it more important than ever that standards are upheld and reviewed. We conclude that the proposal of a new or refined method must be supported by substantial contextual discussion, a robust rationale and analyses and comprehensive documentation
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