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Chapter 9: Occurrence of small mammals: Deer mice and challenge of trapping across large spatial extents
Small mammal communities living in sagebrush ( Artemisia spp. ) may be sensitive to habitat isolation and invasion by exotic grass species. Yet there have been no spatially explicit models to improve our understanding of landscape-scale factors determining small mammal occurrence or abundance. We live-trapped small mammals at 186 locations in the Wyoming Basin Ecoregional Assessment area to develop species distribution (habitat) models for each species. Most small mammal species (n = 14) were trapped at a only few locations. As a result, we developed a small mammal model only for the deer mouse ( Peromyscus maniculatus ). Deer mice were associated with areas having moderately productive habitat as measured by Normalized Difference Vegetation Index (NDVI), increased grassland land cover, contagion of sagebrush land cover, and proximity to intermittent water. The proportion of big sagebrush ( Artemisia tridentata ) within 0.27 km, proportion of mixed shrubland within 5 km, soil clay content, and proximity to pipelines were inversely related to the occurrence of deer mice. Understanding habitat characteristics for deer mice helps our overall understanding of the ecological processes within sagebrush habitats because deer mice act as predator, prey, competitor, and disease reservoir. Development of the empirical data necessary for spatially explicit habitat modeling of small mammal distributions at large spatial extents requires an extensive trapping effort in order to obtain enough observations to construct models, calculate robust detectability estimates, and overcome issues such as trap shyness and population cycling.
Challenges in real-time data collection at active volcanoes in the Pacific Northwest, the Philippines, and Alaska [abs.]
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Organizations challenged by global database development
Several international programs have identified the need for a global 1-kilometer spatial database for land cover and land characterization studies. In 1992, the US Geological Survey (USGS) EROS Data Center (EDC), the European Space Agency (ESA), the National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA) will collect and archive all 1-kilometer Advanced Very High Resolution Radiometer (AVHRR) data acquired during afternoon orbital passes over land.
The increasingly complex challenge of gas hydrate reservoir simulation
No abstract available.
Challenges in recovering resources from acid mine drainage
Metal recovery from mine waters and effluents is not a new approach but one that has occurred largely opportunistically over the last four millennia. Due to the need for low-cost resources and increasingly stringent environmental conditions, mine waters are being considered in a fresh light with a designed, deliberate approach to resource recovery often as part of a larger water treatment evaluation. Mine water chemistry is highly dependent on many factors including geology, ore deposit composition and mineralogy, mining methods, climate, site hydrology, and others. Mine waters are typically Ca-Mg-SO4±Al±Fe with a broad range in pH and metal content. The main issue in recovering components of these waters having potential economic value, such as base metals or rare earth elements, is the separation of these from more reactive metals such as Fe and Al. Broad categories of methods for separating and extracting substances from acidic mine drainage are chemical and biological. Chemical methods include solution, physicochemical, and electrochemical technologies. Advances in membrane techniques such as reverse osmosis have been substantial and the technique is both physical and chemical. Biological methods may be further divided into microbiological and macrobiological, but only the former is considered here as a recovery method, as the latter is typically used as a passive form of water treatment.
Unique challenges facing Southwestern tribes: Chapter 17
Executive Summary When considering climate change, risks to Native American lands, people, and cultures are noteworthy. Impacts on Native lands and communities are anticipated to be both early and severe due to their location in marginal environments. Because Native American societies are socially, culturally, and politically unique, conventional climate change adaptation planning and related policies could result in unintended consequences or conflicts with Native American governments, or could prove to be inadequate if tribal consultation is not considered. Therefore, it is important to understand the distinct historical, legal, and economic contexts of the vulnerability and adaptive capacity of Southwestern Native American communities. The key messages presented in this chapter are: • Vulnerability of Southwestern tribes is higher than that for most groups because it is closely linked to endangered cultural practices, history, water rights, and socio-economic and political marginalization, characteristics that most Indigenous people share. (high confidence) • Very little data are available that quantify the changes that are occurring or that establish baseline conditions for many tribal communities. Additional data are crucial for understanding impacts on tribal lands for resource monitoring and scientific studies. (high confidence) • The scant data available indicate that at least some tribes may already be experiencing climate change impacts. (medium confidence) • Tribes are taking action to address climate change by instituting climate-change mitigation initiatives, including utility-scale, alternative-energy projects, and energy-conservation projects. Tribes are also evaluating their existing capacity to engage in effective adaptation planning, even though financial and social capital is limited.
Challenges and opportunities in studying and managing striped bass and its hybrids in the 21st Century
No abstract available.
Methylmercury contamination of aquatic ecosystems: A widespread problem with many challenges for the chemical sciences
No abstract available.
Status of the threatened Chiricahua Leopard Frog and conservation challenges in Sonora, Mexico, with notes on other ranid frogs and non-native predators
In North America, ranid frogs (Ranidae) have experienced larger declines than any other amphibian family, particularly species native to the southwestern USA and adjacent Mexico; however, our knowledge of their conservation status and threats is limited in Mexico. We assessed the status of the federally listed as threatened (USA) Chiricahua Leopard Frog ( Lithobates chiricahuensis ) in Sonora, Mexico, based on a search of museum specimens, published records, unpublished accounts, and surveys from 2000–2016 of 84 sites within the geographical and elevational range of the species. We also provide information on occurrence of three other native ranid frog species encountered opportunistically during our surveys. The Chiricahua Leopard Frog is known in Sonora from only 20 historical (pre-2000) localities. Searches of three historical sites did not reveal any Chiricahua Leopard Frogs; however, we found it at three previously undocumented sites in 2016, all near Cananea. To our knowledge, these records are the first observations of Chiricahua Leopard Frogs in Sonora since 1998. Differences in conservation status between the USA and Sonora are likely due to differing magnitude and distribution of threats and a comparatively aggressive recovery program in the USA. For example, key non-native predators important in the decline of the Chiricahua Leopard Frog are much less widespread in Sonora compared to the southwestern USA, but there are fewer protections and recovery actions for the frog in Sonora than in the USA. Additional surveys for the Chiricahua Leopard Frog and other amphibians in Sonora should be a priority to fully assess threats and conservation status.
The Life of P: A biogeochemical and sociopolitical challenge in the Everglades
• Phosphorus (P) is an essential element for all life forms, yet to understand its life cycle and impact we need to grasp not only the biogeochemical life of P, but also how P intersects with human activities and values. • Phosphorus is the limiting nutrient in the oligotrophic Everglades ecosystem. Thus, the anthropogenic addition of P to the landscape and its subsequent transport, transformation, and persistence throughout the Everglades are critical to both the visual appearance and the ecological integrity of the Everglades ecosystem. • Legal and political attention to P in the Everglades have created a powerful social-cultural legacy. This legacy includes the continuing influence of P in Everglades restoration, the dissemination of knowledge about P cycling and mitigation among rural and urban Everglades residents, and social and political realignment of management priorities. • Management decisions based on legal mandates require not only robust scientific data about P-related processes, but also information on the behavior, well-being, and political decisions of tribal nations, agricultural enterprises, anglers, and others who use the South Florida landscape.
Global status of trout and char: Conservation challenges in the twenty-first century
Freshwater ecosystems are among the most threatened ecosystems in the world (Richter et al. 1997; Strayer and Dudgeon 2010), and freshwater fishes may now be the most threatened group of vertebrates (Ricciardi and Rasmussen 1999; Vorosmarty et al. 2010; Darwall and Freyhof 2016). Of the 7,300 freshwater fish species globally assessed by the International Union for Conservation of Nature (IUCN, www.iucnredlist.org) in 2013, nearly one of every three species was threatened with extinction (Darwall and Freyhof 2016). Growing pressures from a multitude of direct and indirect human stressors (e.g., habitat loss and degradation, pollution, invasive species, overexploitation, diversion or alteration of biological flows, climate change, and others) threaten the persistence of many freshwater fish species and entire aquatic communities around the globe (Limburg et al. 2011). This pattern is particularly true for salmonid fishes (family Salmonidae, subfamily Salmoninae, belonging to the genera Oncorhynchus, Salvelinus, Salmo, Hucho, Parahucho, Brachymystax, and Salvethymus). Salmonids are globally-distributed, coldwater taxa with life-cycles restricted entirely to freshwater ecosystems (typically referred to as trout and char), but also Atlantic and Pacific salmon with more complex anadromous life-histories.
California's Central Valley wintering waterfowl: Concerns and challenges
No abstract available.
Challenges in the assessment and classification of enhanced/engineered geothermal system resources
No abstract available.
Progress and challenges toward the development of a uniform moment magnitude catalog for eastern Canada
No abstract available.
ShakeAlert® earthquake warning: The challenge of transforming ground motion into protective actions
The USGS ShakeAlert® earthquake early warning (EEW) system is operational and providing public alerting in three West Coast states: California, Washington, and Oregon. Since 2006 the USGS has pursued a strategy of incrementally developing and rolling out EEW for increasingly larger areas and uses. As funding from federal and state budgets grew the system became more capable, detection methods were developed and improved, core network sensor stations were built or upgraded, and partners were enlisted to deliver alerts and implement protective actions. In the fall of 2018, the system became sufficiently functional to publicly declare it “open for business” in all three states for use by licensed partners to alert personnel in limited settings and take automated machine-to-machine actions. State-wide public alerting began in California in October of 2019, expanded to Oregon in March of 2021, and to Washington in May of 2021. Today millions of people can receive ShakeAlert-powered EEW through a variety of delivery methods and dozens of machine-to-machine protective systems are in place in transportation systems, utilities, fire stations, schools, hospitals, and public and private buildings. The ShakeAlert System implementation plan calls for a supporting network of 1,675 seismic stations. 1,129 (73%) have been completed and the rest should be done by 2025.