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USGS2014

The Pedestrian Evacuation Analyst: geographic information systems software for modeling hazard evacuation potential

Recent disasters such as the 2011 Tohoku, Japan, earthquake and tsunami; the 2013 Colorado floods; and the 2014 Oso, Washington, mudslide have raised awareness of catastrophic, sudden-onset hazards that arrive within minutes of the events that trigger them, such as local earthquakes or landslides. Due to the limited amount of time between generation and arrival of sudden-onset hazards, evacuations are typically self-initiated, on foot, and across the landscape (Wood and Schmidtlein, 2012). Although evacuation to naturally occurring high ground may be feasible in some vulnerable communities, evacuation modeling has demonstrated that other communities may require vertical-evacuation structures within a hazard zone, such as berms or buildings, if at-risk individuals are to survive some types of sudden-onset hazards (Wood and Schmidtlein, 2013). Researchers use both static least-cost-distance (LCD) and dynamic agent-based models to assess the pedestrian evacuation potential of vulnerable communities. Although both types of models help to understand the evacuation landscape, LCD models provide a more general overview that is independent of population distributions, which may be difficult to quantify given the dynamic spatial and temporal nature of populations (Wood and Schmidtlein, 2012). Recent LCD efforts related to local tsunami threats have focused on an anisotropic (directionally dependent) path distance modeling approach that incorporates travel directionality, multiple travel speed assumptions, and cost surfaces that reflect variations in slope and land cover (Wood and Schmidtlein, 2012, 2013). The Pedestrian Evacuation Analyst software implements this anisotropic path-distance approach for pedestrian evacuation from sudden-onset hazards, with a particular focus at this time on local tsunami threats. The model estimates evacuation potential based on elevation, direction of movement, land cover, and travel speed and creates a map showing travel times to safety (a time map) throughout a hazard zone. Model results provide a general, static view of the evacuation landscape at different pedestrian travel speeds and can be used to identify areas outside the reach of naturally occurring high ground. In addition, data on the size and location of different populations within the hazard zone can be integrated with travel-time maps to create tables and graphs of at-risk population counts as a function of travel time to safety. As a decision-support tool, the Pedestrian Evacuation Analyst provides the capability to evaluate the effectiveness of various vertical-evacuation structures within a study area, both through time maps of the modeled travel-time landscape with a potential structure in place and through comparisons of population counts within reach of safety. The Pedestrian Evacuation Analyst is designed for use by researchers examining the pedestrian-evacuation potential of an at-risk community. In communities where modeled evacuation times exceed the event (for example, tsunami wave) arrival time, researchers can use the software with emergency managers to assess the area and population served by potential vertical-evacuation options. By automating and managing the modeling process, the software allows researchers to concentrate efforts on providing crucial and timely information on community vulnerability to sudden-onset hazards.

Techniques and Methods↗
USGS2014

A methodological toolkit for field assessments of artisanally mined alluvial diamond deposits

This toolkit provides a standardized checklist of critical issues relevant to artisanal mining-related field research. An integrated sociophysical geographic approach to collecting data at artisanal mine sites is outlined. The implementation and results of a multistakeholder approach to data collection, carried out in the assessment of Guinea’s artisanally mined diamond deposits, also are summarized. This toolkit, based on recent and successful field campaigns in West Africa, has been developed as a reference document to assist other government agencies or organizations in collecting the data necessary for artisanal diamond mining or similar natural resource assessments.

Techniques and Methods↗
USGS2005

ShakeMap manual: technical manual, user's guide, and software guide

ShakeMap (http://earthquake.usgs.gov/shakemap) --rapidly, automatically generated shaking and intensity maps--combines instrumental measurements of shaking with information about local geology and earthquake location and magnitude to estimate shaking variations throughout a geographic area. The results are rapidly available via the Web through a variety of map formats, including Geographic Information System (GIS) coverages. These maps have become a valuable tool for emergency response, public information, loss estimation, earthquake planning, and post-earthquake engineering and scientific analyses. With the adoption of ShakeMap as a standard tool for a wide array of users and uses came an impressive demand for up-to-date technical documentation and more general guidelines for users and software developers. This manual is meant to address this need. ShakeMap, and associated Web and data products, are rapidly evolving as new advances in communications, earthquake science, and user needs drive improvements. As such, this documentation is organic in nature. We will make every effort to keep it current, but undoubtedly necessary changes in operational systems take precedence over producing and making documentation publishable.

Techniques and Methods↗
USGS2017

PRISM software—Processing and review interface for strong-motion data

Rapidly available and accurate ground-motion acceleration time series (seismic recordings) and derived data products are essential to quickly providing scientific and engineering analysis and advice after an earthquake. To meet this need, the U.S. Geological Survey National Strong Motion Project has developed a software package called PRISM (Processing and Review Interface for Strong-Motion data). PRISM automatically processes strong-motion acceleration records, producing compatible acceleration, velocity, and displacement time series; acceleration, velocity, and displacement response spectra; Fourier amplitude spectra; and standard earthquake-intensity measures. PRISM is intended to be used by strong-motion seismic networks, as well as by earthquake engineers and seismologists.

Techniques and Methods↗
USGS2010

MATLAB tools for improved characterization and quantification of volcanic incandescence in Webcam imagery: Applications at Kilauea Volcano, Hawai'i

Webcams are now standard tools for volcano monitoring and are used at observatories in Alaska, the Cascades, Kamchatka, Hawai‘i, Italy, and Japan, among other locations. Webcam images allow invaluable documentation of activity and provide a powerful comparative tool for interpreting other monitoring datastreams, such as seismicity and deformation. Automated image processing can improve the time efficiency and rigor of Webcam image interpretation, and potentially extract more information on eruptive activity. For instance, Lovick and others (2008) provided a suite of processing tools that performed such tasks as noise reduction, eliminating uninteresting images from an image collection, and detecting incandescence, with an application to dome activity at Mount St. Helens during 2007. In this paper, we present two very simple automated approaches for improved characterization and quantification of volcanic incandescence in Webcam images at Kīlauea Volcano, Hawai‘i. The techniques are implemented in MATLAB (version 2009b, ® The Mathworks, Inc.) to take advantage of the ease of matrix operations. Incandescence is a useful indictor of the location and extent of active lava flows and also a potentially powerful proxy for activity levels at open vents. We apply our techniques to a period covering both summit and east rift zone activity at Kīlauea during 2008–2009 and compare the results to complementary datasets (seismicity, tilt) to demonstrate their integrative potential. A great strength of this study is the demonstrated success of these tools in an operational setting at the Hawaiian Volcano Observatory (HVO) over the course of more than a year. Although applied only to Webcam images here, the techniques could be applied to any type of sequential images, such as time-lapse photography. We expect that these tools are applicable to many other volcano monitoring scenarios, and the two MATLAB scripts, as they are implemented at HVO, are included in the appendixes. These scripts would require minor to moderate modifications for use elsewhere, primarily to customize directory navigation. If the user has some familiarity with MATLAB, or programming in general, these modifications should be easy. Although we originally anticipated needing the Image Processing Toolbox, the scripts in the appendixes do not require it. Thus, only the base installation of MATLAB is needed. Because fairly basic MATLAB functions are used, we expect that the script can be run successfully by versions earlier than 2009b.

Hawaii↗
USGS2015

A multipurpose camera system for monitoring Kīlauea Volcano, Hawai'i

We describe a low-cost, compact multipurpose camera system designed for field deployment at active volcanoes that can be used either as a webcam (transmitting images back to an observatory in real-time) or as a time-lapse camera system (storing images onto the camera system for periodic retrieval during field visits). The system also has the capability to acquire high-definition video. The camera system uses a Raspberry Pi single-board computer and a 5-megapixel low-light (near-infrared sensitive) camera, as well as a small Global Positioning System (GPS) module to ensure accurate time-stamping of images. Custom Python scripts control the webcam and GPS unit and handle data management. The inexpensive nature of the system allows it to be installed at hazardous sites where it might be lost. Another major advantage of this camera system is that it provides accurate internal timing (independent of network connection) and, because a full Linux operating system and the Python programming language are available on the camera system itself, it has the versatility to be configured for the specific needs of the user. We describe example deployments of the camera at Kīlauea Volcano, Hawai‘i, to monitor ongoing summit lava lake activity.

Hawai'i↗
USGS2018

Operational tracking of lava lake surface motion at Kīlauea Volcano, Hawai‘i

Surface motion is an important component of lava lake behavior, but previous studies of lake motion have been focused on short time intervals. In this study, we implement the first continuous, real-time operational routine for tracking lava lake surface motion, applying the technique to the persistent lava lake in Halema‘uma‘u Crater at the summit of Kīlauea Volcano, Hawai‘i. We measure lake motion by using images from a fixed thermal camera positioned on the crater rim, transmitting images to the Hawaiian Volcano Observatory (HVO) in real time. We use an existing optical flow toolbox in Matlab to calculate motion vectors, and we track the position of lava upwelling in the lake, as well as the intensity of spattering on the lake surface. Over the past 2 years, real-time tracking of lava lake surface motion at Halema‘uma‘u has been an important part of monitoring the lake’s activity, serving as another valuable tool in the volcano monitoring suite at HVO.

Hawai‘i↗
USGS2013

Modeling crustal deformation near active faults and volcanic centers: a catalog of deformation models and modeling approaches

This manual provides the physical and mathematical concepts for selected models used to interpret deformation measurements near active faults and volcanic centers. The emphasis is on analytical models of deformation that can be compared with data from the Global Positioning System (GPS) receivers, Interferometric synthetic aperture radar (InSAR), leveling surveys, tiltmeters and strainmeters. Source models include pressurized spherical, ellipsoidal, and horizontal penny-shaped geometries in an elastic, homogeneous, flat half-space. Vertical dikes and faults are described following the mathematical notation for rectangular dislocations in an elastic, homogeneous, flat half-space. All the analytical expressions were verified against numerical models developed by use of COMSOL Multyphics, a Finite Element Analysis software (http://www.comsol.com). In this way, typographical errors present were identified and corrected. Matlab scripts are also provided to facilitate the application of these models.

Techniques and Methods↗
USGS2018

THRESH—Software for tracking rainfall thresholds for landslide and debris-flow occurrence, user manual

Precipitation thresholds are used in many areas to provide early warning of precipitation-induced landslides and debris flows, and the software distribution THRESH is designed for automated tracking of precipitation, including precipitation forecasts, relative to thresholds for landslide occurrence. This software is also useful for analyzing multiyear precipitation records to compare timing of threshold exceedance with dates and times of historical landslides. This distribution includes the main program THRESH for comparing precipitation to several kinds of thresholds, two utility programs, and a small collection of Python and shell scripts to aid the automated collection and formatting of input data and the graphing and further analysis of output results. The software programs can be deployed on computing platforms that support Fortran 95, Python 2, and certain Unix commands. The software handles rainfall intensity-duration thresholds, cumulative recent-antecedent precipitation thresholds, and peak intensity thresholds as well as various measures of antecedent precipitation. Users should have predefined rainfall thresholds before running THRESH.

Techniques and Methods↗
USGS2015

Field Manual of Wildlife Diseases

Welcome to a new version of the “Field Manual of Wildlife Diseases.” Unlike the previous printed versions of this publication, this new version is being developed as a “living“ electronic publication. Content will periodically be added and (or) updated as warranted, and it will always be reviewed by scientific experts (“peer reviewed”) before it is released. Thus, this publication will never be completed, and readers should download revised versions of specific chapters, glossaries, and the appendixes whenever they visit the publication Web site. The purpose of this manual is to provide information that will enhance the ecological understanding and comfort level of nonspecialists so that they can address various aspects of wildlife disease within the context of wildlife conservation and management. Other readers, from students to science professionals, may also find the information presented to be of interest and value. Constructive suggestions from readers will help guide adjustments as this project progresses. We begin this new manual with introductory contextual and historical background about the convergence of wildlife disease with wildlife management as a wildlife conservation concern (section A, chap. 1). The remainder of the publication is focused on pragmatic information and considerations for addressing various aspects of wildlife disease. Section B focuses on concepts associated with disease surveillance and response to outbreaks, and section C deals with specific techniques for disease surveillance and investigation. Section D, “Diseases of Wild Birds,” and others that follow will address diseases of concern in various species groups. Electronic links facilitate timely access to a wide variety of supplemental information and processes relevant to content in this new version of the “Field Manual of Wildlife Diseases.”

Techniques and Methods↗
USGS2015

Introduction

This is the third iteration of the National Wildlife Health Center's (NWHC) field guide developed primarily to assist field managers and biologists address diseases they encounter. By itself, the first iteration, “Field Guide of Wildlife Diseases: General Field Procedures and Diseases of Migratory Birds,” was simply another addition to an increasing array of North American field guides and other publications focusing on disease in free-ranging wildlife populations. Collectively, those publications were reflecting the ongoing transition in the convergence of wildlife management and wildlife disease as foundational components within the structure of wildlife conservation as a social enterprise serving the stewardship of our wildlife resources. For context, it is useful to consider those publications relative to a timeline of milestones involving the evolution of wildlife conservation in North America.

Techniques and Methods↗
USGS2015

Mortality investigation

Wildlife mortality events usually occur unannounced and may find management agencies unaware. These events can become highly visible and politically charged affairs, depending upon the scale or species involved. The public, media, and (or) politicians may pressure managers, field investigators, and diagnosticians to quickly identify the cause or to comment on potential causes, the significance of the event, what is being done about it, and a resolution. It may be common during such events for speculation to rage, and for conflicting theories to be advanced to explain either the environmental conditions that led to the mortality or the actual cause of death. The overarching goal of a wildlife mortality investigation is to determine what happened and to identify causative factors that may have led to the event. Steps include obtaining the relevant history (defined later), conducting on-site field evaluations when necessary, collecting suitable samples, and completing appropriate diagnostic laboratory analyses. These procedures allow diagnosticians and biologists to determine the potential cause of mortality as swiftly as possible, or at the very least, to systematically eliminate potential causes of mortality so as to allow managers to focus on the most probable cause. Investigating mortalities in free-ranging wildlife poses a series of challenges requiring careful preparation, clear evaluation of objectives, and flexible implementation.

Techniques and Methods↗
USGS2020

Safe work practices for working with wildlife

Most wildlife biologists, technicians, and veterinarians complete their tasks safely and uneventfully every day. However, some significant risks exist in this line of work, and injuries, illnesses, and accidental deaths among wildlife workers do occur. Aviation accidents (airplane and helicopter), drownings, and car and truck accidents are the most common causes of fatalities among wildlife workers (Sasse, 2003). Although rare, serious zoonotic infections also happen. Being mindful of occupational hazards and zoonoses (diseases transmitted between humans and animals), and the various ways to minimize these risks, can help workers stay safe and healthy on the job.

Techniques and Methods↗
USGS2016

Recording and submitting specimen history data

Summary In wildlife disease investigations, determining the history or background of a problem is the first significant step toward establishing a diagnosis and aiding agencies with management considerations. The diagnostic process and overall investigation is often greatly expedited by a chronological record accompanying specimens submitted for laboratory evaluation. Knowing where and when the outbreak is taking place, what the environmental conditions and species involved are, and clinical signs in sick animals, along with necropsy findings and diagnostic test results are important for understanding the natural history or epizootiology of disease outbreaks. It becomes increasingly difficult to retrospectively obtain all of the pertinent history as time passes. The most helpful information is that which is obtained at the time of the die-off event by perceptive field biologists and other observers. Significant events preceding morbidity and/or mortality also provide valuable information on which to base corrective actions. In this chapter, readers will find information regarding what type of information should be recorded, how it should be recorded and why it is relevant to a disease investigation. A thoughtful approach in providing as much information as possible surrounding the situation including about host species and the biotic and abiotic environment, greatly aids in determining the most likely causative agent(s).

Techniques and Methods↗
USGS2015

Wildlife specimen collection, preservation, and shipment

Specimens are used to provide supporting information leading to the determination of the cause of disease or death in wildlife and for disease monitoring or surveillance. Commonly used specimens for wildlife disease investigations include intact carcasses, tissues from carcasses, euthanized or moribund animals, parasites, ingested food, feces, or environmental samples. Samples from live animals or the environment (e.g., contaminated feed) in the same vicinity as a mortality event also may be helpful. The type of specimen collected is determined by availability of samples and biological objectives. Multiple fresh, intact carcasses from affected species are the most useful in establishing a cause for a mortality event. Submission of entire carcasses allows observation of gross lesions and abnormalities, as well as disease testing of multiple tissues. Samples from live animals may be more appropriate when sick animals cannot be euthanized (e.g., threatened or endangered species) or for research and monitoring projects examining disease or agents circulating in apparently healthy animals or those not exhibiting clinical signs. Samples from live animals may include collections of blood, hair, feathers, feces, or ectoparasites, or samples obtained by swabbing lesions or orifices. Photographs and videos are useful additions for recording field and clinical signs and conveying conditions at the site. Collection of environmental samples (e.g., feces, water, feed, or soil) may be appropriate when animals cannot be captured for sampling or the disease agent may persist in the environment. If lethal collection is considered necessary, biologists should refer to the policies, procedures, and permit requirements of their institution/facility and the agency responsible for species management (U.S. Fish and Wildlife Service or State natural resource agency) prior to use in the field. If threatened or endangered species are found dead, or there is evidence of illegal take, field personal should contact local wildlife law enforcement authorities immediately and prior to handling the carcass. Prior to collecting samples, it is important to determine the capabilities and submission criteria of the laboratory receiving the samples. Some laboratories may specialize in a limited number of tests, be equipped to accept only certain types of tissues (instead of entire carcasses), or specialize in particular species or group of animals (e.g., reptiles, birds, mammals). Diagnostic laboratories have specific requirements regarding preparation, labeling, and shipping of samples. Adherence to these requirements helps ensure the usefulness of any submitted specimens. Although laboratories may vary in the cost and turnaround times for diagnostic tests, some laboratories may be able to prioritize samples and accommodate accelerated time frames if communicated at the time of submission. Keeping a prepacked kit with basic carcass-collection supplies, including a paper copy of the specimen history form (available for download from the Web sites of most diagnostic laboratories), in the office or vehicle will decrease the chances of forgetting an essential item and decrease response time for arriving at an event.

Techniques and Methods↗
USGS2015

Special considerations for specimen collections that may be involved in law enforcement cases

Causes of mortality in wildlife include natural conditions—such as the viral, bacterial, and fungal diseases discussed in other chapters of this manual—and human intervention. Direct human intervention in wildlife deaths may be associated with individual human actions, such as gunshot or poisonings, or with institutions, such as wind farms or mining operations. Mortality that can be directly attributed to humans may be considered a crime based on the animal(s) affected and (or) the agent used. Wildlife laws were established to protect our nation’s wildlife resources and assist in conserving healthy populations of native wildlife. A variety of laws pertain to wildlife, such as the Migratory Bird Treaty Act, which makes it illegal, except as permitted, to capture, kill, or possess a portion or all of any migratory bird, a member of the group that includes the vast majority of wild birds present in the United States. Similar to pathogens that can spread unchecked through a wild population, a person or an institution that illegally kills wildlife may continue this practice indefinitely or until the illegal activities are detected and addressed. Convicting the perpetrator of a crime, however, requires that certain practices and procedures be followed so that a solid legal case can be constructed. As with any crime, investigation of the event is led by law enforcement personnel who are well-versed in the applicable laws, oversee the collection of evidence, and pursue persons or entities of interest. These individuals are uniquely qualified and trained to maintain the integrity of evidence, evaluate suspects to effectively prosecute the case, and effect the penalties of the law. The investigation of direct crimes against humans may involve teams of 5–10 law enforcement agents and specialists—each with a certain focus such as blood spatter, fingerprints, or ballistics—in processing a crime scene. In contrast, investigations of crimes against wildlife generally involve markedly fewer wildlife law enforcement agents, and in many instances of unlawful wildlife death, only one law enforcement agent is available to process an entire crime scene and work on a case. Thus, the assistance of individuals familiar with the geographical area, the endemic animal populations, and the local ecology can be very important for building an effective case. The aims of this chapter are to 1) help biologists or field personnel recognize the signs that indicate a crime may have been committed, and 2) to give readers a basic understanding of how a wildlife crime scene is processed. This chapter is not intended to give readers the tools to investigate a crime scene alone, but will hopefully make them a valuable asset to law enforcement agents who respond to the scene. An effectively processed case, resulting in prosecution of a suspect, supports the law as a deterrent to future acts that could endanger the conservation of wildlife.

Techniques and Methods↗
USGS2020

Human dimensions considerations in wildlife disease management

In 1943, Aldo Leopold observed that the real problem of wildlife management is not how to handle wildlife, but how to manage humans. As with any other aspect of wildlife management, social sciences can improve understanding the human dimensions of wildlife disease management (WDM). Human activities have accelerated the emergence of wildlife diseases, and human concerns about the ecological, social, and economic impacts of wildlife diseases and their management have led to diseases becoming headline-worthy public issues. This chapter provides guidance to help front-line professionals understand and address the public’s perspectives and behaviors relevant to WDM. This chapter focuses on practical needs of wildlife disease managers who have to consider and interact with specific stakeholders and the broader public. The chapter does not dive deeply into social science; instead it briefly reviews some concepts that are most relevant to WDM. The chapter also suggests where to look for assistance and additional resources for further reading. Following brief introductory comments, the chapter is organized around a simple model of the general process for WDM. It addresses three key areas where social science can assist in WDM—audience research to understand stakeholders; engaging stakeholders in wildlife disease management; and using risk communication about wildlife diseases and disease management to inspire risk-wise behavior.

Techniques and Methods↗
USGS2015

Information resources

During recent decades, natural resources agency personnel and others involved with the management and stewardship of wildlife have experienced an increasing need to access information and obtain technical assistance for addressing a diverse array of wildlife disease issues. This Chapter provides a broad overview of selected sources for obtaining supplemental information and technical assistance for addressing wildlife disease issues in North America. Specifically, examples of existing major wildlife disease programs focusing on free-ranging wildlife populations are highlighted; training opportunities for enhancing within-agency wildlife disease response are identified; a selected reading list of wildlife disease references is provided; and selected Web sites providing timely information on wildlife disease are highlighted. No attempt is made to detail all the North American programs and capabilities that address disease in free-ranging wildlife populations. Instead, this Chapter is focused on enhancing awareness of the types of capabilities that exist as potential sources for assistance and collaboration between wildlife conservation agency personnel and others in addressing wildlife disease issues. A wide variety of entities across North America are involved in wildlife disease investigations; however, the formal assembly of multidimensional programs that primarily address disease for the benefit of free-ranging wildlife is rather limited. The Southeastern Cooperative Wildlife Disease Study (SCWDS), the National Wildlife Health Center (NWHC), and the Canadian Wildlife Health Cooperative (CWHC) are selected examples. These programs are highlighted because of the scope of their capabilities and long-term involvement in assisting State and Federal natural resource agencies combat wildlife disease. A variety of other sources for possible assistance in addressing wildlife disease issues exists throughout North America and globally. It is prudent for wildlife conservation field biologists, managers, and administrators to be aware of such local resources. Ideally, awareness and knowledge of the types of assistance those programs can provide should be obtained prior to disease crisis events since appropriate, timely intervention often is required to minimize wildlife losses from disease and prevent the establishment of new infectious diseases within wildlife populations and geographic areas. Increasing recognition of the substantial number of infectious diseases being transferred between wildlife, domestic animals, and humans has led to increased collaborative investigations between wildlife, domestic, and human health programs. That collaboration has led to a heightened focus on wildlife disease within some public health and agriculture agencies. For purposes of this Chapter, wildlife disease is narrowly defined as those diseases (infectious and noninfectious) causing morbidity and mortality in free-ranging wildlife populations. Therefore, there is no focus on the numerous fish disease or environmental contaminant programs that exist on behalf of North American fauna.

Techniques and Methods↗