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Guidelines for determining flood flow frequency: Bulletin #17B of the Hydrology Subcommittee

In December 1967, Bulletin No. 15, "A Uniform Technique for Determining Flood Flow Frequencies," was issued by the Hydrology Committee of the Water Resources Council. The report recommended use of the Pearson Type III distribution with log transformation of the data (log-Pearson Type III distribution) as a base method for flood flow frequency studies. As pointed out in that report, further studies were needed covering various aspects of flow frequency determinations. In March 1976, Bulletin 17, "Guidelines for Determining Flood Flow Frequency" was issued by the Water Resources Council. The guide was an extension and update of Bulletin No. 15. It provided a more complete guide for flood flow frequency analysis incorporating currently accepted technical methods with sufficient detail to promote uniform application. It was limited to defining flood potentials in terms of peak discharge and exceedance probability at locations where a systematic record of peak flood flows is available. The recommended set of procedures was selected from those used or described in the literature prior to 1976, based on studies conducted for this purpose at the Center for Research in Water Resources of the University of Texas at Austin (summarized in Appendix 14) and on studies by the Work Group on Flood Flow Frequency. The "Guidelines" were revised and reissued in June 1977 as Bulletin 17A. Bulletin 17B is the latest effort to improve and expand upon the earlier publications. Bulletin 17B provides revised procedures for weighting a station skew value with the results from a generalized skew study, detecting and treating outliers, making two station comparisons, and computing confidence limits about a frequency curve. The Work Group that prepared this revision did not address the suitability of the original distribution or the generalized skew map. Major problems are encountered when developing guides for flood flow frequency determinations. There is no procedure or set of procedures that can be adopted which, when rigidly applied to the available data, will accurately define the flood potential of any given watershed. Statistical analysis alone will not resolve all flood frequency problems. As discussed in subsequent sections of this guide, elements of risk and uncertainty are inherent in any flood frequency analysis. User decisions must be based on properly applied procedures and proper interpretation of results considering risk and uncertainty. Therefore, the judgment of a professional experienced in hydrologic analysis will enhance the usefulness of a flood frequency analysis and promote appropriate application. It is possible to standarize many elements of flood frequency analysis. This guide describes each major element of the process of defining the flood potential at a specific location in terms of peak discharge and exceedance probability. Use is confined to stations where available records are adequate to warrant statistical analysis of the data. Special situations may require other approaches. In those cases where the procedures of this guide are not followed, deviations must be supported by appropriate study and accompanied by a comparison of results using the recommended procedures. As a further means of achieving consistency and improving results, the Work Group recommends that studies be coordinated when more than one analyst is working currently on data for the same location. This recommendation holds particularly when defining exceedance probabilities for rare events, where this guide allows more latitude. Flood records are limited. As more years of record become available at each location, the determination of flood potential may change. Thus, an estimate may be outdated a few years after it is made. Additional flood data alone may be sufficient reason for a fresh assessment of the flood potential. When making a new assessment, the analyst should incorporate in his study a review of earlier estimates. Where differences appear, they should be acknowledged and explained.

Bulletin↗

Use of StreamStats in the Upper French Broad River Basin, North Carolina: A Pilot Water-Resources Web Application

StreamStats is a Web-based Geographic Information System (GIS) application that was developed by the U.S. Geological Survey (USGS) in cooperation with Environmental Systems Research Institute, Inc. (ESRI) to provide access to an assortment of analytical tools that are useful for water-resources planning and management. StreamStats allows users to easily obtain streamflow statistics, basin characteristics, and descriptive information for USGS data-collection sites and selected ungaged sites. StreamStats also allows users to identify stream reaches upstream and downstream from user-selected sites and obtain information for locations along streams where activities occur that can affect streamflow conditions. This functionality can be accessed through a map-based interface with the user's Web browser or through individual functions requested remotely through other Web applications.

North Carolina↗

U.S. Geological Survey science in support of the North American Bat Monitoring Program (NABat)

Bats make up one-fifth of all mammalian species worldwide and are found on every continent except Antarctica. They contribute to overall ecosystem health by suppressing pest insects and pollinating plants and spreading seeds. Eight North American bat species are listed as federally endangered or threatened, and more than one-half are of current conservation concern in the United States, Canada, or Mexico. The U.S. Geological Survey (USGS) leads, manages, and coordinates the multinational North American Bat Monitoring Program (NABat) as well as conducts scientific research on bats. USGS and NABat partners help resource managers and policymakers make informed decisions regarding the conservation of bats across North America. USGS science also helps inform decision making with respect to WNS surveillance and bat vulnerability; mitigation of potential impacts of energy development on bats; prelisting conservation efforts for regulatory agencies; and land management practices. Partners are essential to the success of NABat. The data contributed by NABat partners provide baseline knowledge on the distribution and abundance of bats, which is used to evaluate the impacts of the threats to bats across North America. These data are also the foundation for the scientific information used to set conservation priorities and evaluate the effectiveness of management actions.

Fact Sheet↗

Bibliography of fine-grained siliceous deposits

This bibliography was compiled under the auspices of the International Geologic Correlations Project's (IGCP) Research Group 115, "Siliceous Deposits of the Pacific Region"; IGCP is sponsored by UNESCO and the International Union of Geological Sciences (IUGS). Research Group 115 was originally proposed to IGCP in 1974 by Professor Azuma Iijima, University of Tokyo, and is now headed by James R. Hein, U.S. Geological Survey. Cooperative efforts by 86 members from 17 countries help in accomplishing Research Group 115's objectives of correlating sedimentary processes of siliceous deposits in the Pacific Basin and neighboring geosynclinal areas by means of stratigraphy, sedimentology, geochemisty, and paleontology. These correlations will allow us to estimate the geochemical silica budget in the Earth's crust; to estimate the production of silica in the marine environment through geologic time; to formulate a general rule on sedimentation of siliceous deposits in geosynclines; to increase understanding of the development of circum-Pacific orogenic belts; and to obtain basic methods to evaluate siliceous deposits of economic interest. The group agreed to focus on fine-grained siliceous deposits (cherts, siliceous shales, diatomites, and the like) and to exclude quartz sand deposits and quartzose sandstones.

Open-File Report↗

Water resources activities in Kentucky, 1986

The U.S. Geological Survey, Water Resources Division, conducts three major types of activities in Kentucky in order to provide hydrologic information and understanding needed for the best management of Kentucky 's and the Nation 's water resources. These activities are: (1) Data collection and dissemination; (2) Water-resources appraisals (interpretive studies); and (3) Research. Activities described in some detail following: (1) collection of surface - and groundwater data; (2) operation of stations to collect data on water quality, atmospheric deposition, and sedimentation; (3) flood investigations; (4) water use; (5) small area flood hydrology; (6) feasibility of disposal of radioactive disposal in deep crystalline rocks; (7) development of a groundwater model for the Louisville area; (8) travel times for streams in the Kentucky River Basin; (9) the impact of sinkholes and streams on groundwater flow in a carbonate aquifer system; (10) sedimentation and erosion rates at the Maxey Flats Radioactive Waste Burial site; and (11) evaluation of techniques for evaluating the cumulative impacts of mining as applied to coal fields in Kentucky. (Lantz-PTT)

Open-File Report↗

Assessment of a habitat equivalency analysis for freshwater mussels in the upper Mississippi River

The upper Mississippi River (UMR) contains diverse, dense, and reproducing assemblages of native freshwater mussels. In the case of an injury to mussels and their habitats, such as a hazardous material spill, train derailment, or barge grounding, resource managers have few restoration strategies. Resource managers need a means to document, quantify, and mitigate adverse effects on mussels resulting from injury. Habitat equivalency analysis (HEA), developed for use with a wide variety of habitat types, is a restoration scaling technique that compares ecological services lost from injury to ecological services gained through restoration actions. The U.S. Fish and Wildlife Service and Iowa Department of Natural Resources modified the HEA for use with native mussels. The mussel HEA has been applied within the UMR to estimate the quantity of restoration needed to compensate the public for injuries to mussels due to contaminant spills and construction projects. Our objective was to describe the UMR HEA for a general audience and assess if the four biological input variables used in the mussel HEA were reasonable based on literature values. We also evaluated the performance of HEA under a range of input scenarios. Although the input estimates used in HEA were within ranges reported in the peer-reviewed literature or were supported by professional judgment in the absence of peer-reviewed literature, outcomes of the mussel HEA were highly variable and would benefit from additional research to reduce uncertainty in the biological inputs. The application of HEA to mussels provides resource managers with a tool to quantify mussel-related ecological services lost from injury and to guide restoration efforts in the UMR.

Freshwater Mollusk Biology and Conservation↗

Characterizing historic streamflow to support drought planning in the upper Missouri River basin

This project combined tree-ring based paleo and modern climate and hydrologic research aimed at understanding the primary influences on drought risk and water reliability in basins critical for western U.S. water resources. New paleohydrologic datasets and analyses were developed and applied to contextualize future streamflow projections and address specific water management questions. These questions centered around optimizing future water management protocols for numerous objectives ranging from improving agricultural water allocation during drought while maintaining instream flows for aquatic ecosystem health, to the testing of operations across large river systems with complex infrastructure critical for downstream flood control, navigation, and hydropower generation. USGS scientists worked closely with the Bureau of Reclamation to estimate both past and future drought risk at key management locations throughout the Missouri basin, the Milk and St. Mary River system, and across the major managed river systems in the western United States. These efforts provided a roadmap for future water management strategies under changing climate and water supply conditions, which are detailed in Reclamation’s newly completed Missouri Headwaters Basin Study, the 2021 SECURE Water Act Report, and the forthcoming update of the St. Mary and Milk Rivers Basin Study. Among the major scientific findings to emerge was a new understanding of the long-term (1200-year) history of drought variability for the Missouri River, which highlighted the unusual severity of the early 2000s drought across the Rocky Mountain headwaters and adjacent high plains. By combining the extended drought record with extensive modern and paleoclimate records, we document how warming exacerbates severities of naturally occurring droughts, with recent decades defined by “hot” droughts and the 2000s (2001-2010) drought ranking as the most severe event in 1200 years. Increasingly severe drought events such as this strain already over-allocated water resources that multiple sectors of society depend heavily upon.

upper Missouri River basin↗

Basin characteristics for selected streamflow-gaging stations in and near West Virginia

Basin characteristics have long been used to develop equations describing streamflow. In the past, flow equations used in West Virginia were based on a few hand-calculated basin characteristics. More recently, the use of a Geographic Information System (GIS) to generate basin characteristics from existing datasets has refined the process for developing equations to describe flow values in the Mountain State. These basin characteristics are described in this document for streamflow-gaging stations in and near West Virginia. The GIS program developed in ArcGIS Workstation by Environmental Systems Research Institute (ESRI?) used data that included National Elevation Dataset (NED) at 1:24,000 scale, climate data from the National Oceanic and Atmospheric Agency (NOAA), streamlines from the National Hydrologic Dataset (NHD), and LandSat-based land-cover data (NLCD) for the period 1999-2003. Full automation of data generation was not achieved due to some inaccuracies in the elevation dataset, as well as inaccuracies in the streamflow-gage locations retrieved from the National Water Information System (NWIS). A Pearson?s correlation examination of the data indicates that several of the basin characteristics are correlated with drainage area. However, the GIS-generated data provide a consistent and documented set of basin characteristics for resource managers and researchers to use.

West Virginia↗

A workshop model simulating fate and effect of drilling muds and cuttings on benthic communities

Oil and gas exploration and production at marine sites has generated concern over potential environmental impacts resulting from the discharge of spent drilling muds and cuttings. This concern has led to a broad array of publicly and privately sponsored research. This report described a cooperative modeling effort designed to focus information resulting from this research through construction of explicit equations that simulate the potential impacts of discharge drilling fluids (muds) and cuttings on marine communities. The model is the result of collaboration among more than 30 scientists. The principal cooperating organizations were the E.S. Environmental Protection Agency, the U.S. Minerals Management Service, the Offshore Operators Committee, and the Alaska Oil and Gas Association. The overall simulation model can be conceptualized as three connected submodels: Discharge and Plume Fate, Sediment Redistribution, and Benthic Community Effects. On each day of simulation, these submodels are executed in sequence, with flows of information between submodels. The Benthic Community Effects submodel can be further divided into sections that calculate mortality due to burial, mortality due to toxicity, mortality due to resuspension disturbance, and growth of the community. The model represents a series of seven discrete 1-m 2 plots at specified distances along a transect in one direction away from a discharge point. It consists of coupled difference equations for which parameter values can easily be set to evaluate different conditions or to examine the sensitivity of output to various assumptions. Sets of parameter values were developed to represent four general cases or scenarios: (1) a shallow (5 m), cold environment with ice cover during a substantial fraction of the year, such as might be encountered in the Beaufort Sea, Alaska; (2) a shallow (20 m), temperate environment, such as might be encountered in the Gulf of Mexico; (3) a deeper (80 m), temperate environment, such as might be encountered in the Gulf of Mexico; and (4) a very deep (1,000 m) environment, such as might be encountered on the Atlantic slope. The focus of the modeling effort was on the connection of a reasonable representation of physical fate to the biological responses of populations, rather than on highly detailed representations of individual processes. For example, the calculations of physical fate are not as detailed as those in the recently published model of Brandsma et al. (1983). The value of the model described herein is in the broad scope of processes that are explicitly represented and linked together. The model cannot be considered to produce reliable predictions of the quantitative impacts of discharged drilling fluids and cuttings on biological populations at a particular site. Limitations of the model in predicting integrated fate and effects can be traced to three general areas: level of refinement of the algorithms used in the model; lack of understanding of the processes determining fate and effects; and parameter and data values. Despite the limitations, several qualitative conclusions concerning both potential impacts and the importance of various remaining data gaps can be drawn from the modeling effort. These include: (1) Simple, unequivocal conclusions about fate and effects across geographical regions and drilling operations are difficult, if not misleading, due to the large amount of variability in characteristics of discharged materials (e.g., oil content and toxicity), discharge conditions (e.g., duration of drilling operations), physical environments (e.g., water depth, current direction, and sediment disturbance regimes), and biological communities (e.g., intrinsic growth rates). Different combinations of these characteristics can result in substantial differences in simulated environmental fate and biological effects. For examples, simulated recovery in some high-energy environments occurs within months after the cessation of discharge operations, even at heavily impacted sites, whereas simulated recover in some low-energy environments takes years at heavily impacted sites. <2) Considerable difficulties remain in the reliable extrapolation of results from laboratory toxicity experiments to predictions of population effects in the field. (3) The volume of material discharged and duration of operations in the production drilling operations simulated by the model are sufficient to produce substantial simulated biological impacts at some plots, both in terms of differences from a control plot during the period of discharge operations, and in terms of the recovery period following the perturbations. Evaluation of the significance of potential effects involves the following factors: • Definition of a specific spatial and temporal reference frame (e.g., What is the natural variation? Is 1 year to be considered a "long" or "short" time? Is 50 m to be considered a "large" or "trivial" distance? • Consideration of rare or unique resources and particularly sensitive biotic assemblages. • Consideration of the potential for long term, cumulative effects. Some of these aspects are clearly beyond the scope of this modeling efforts (e.g., the model does not simulate the long term fate of resuspended material). The model does, however, contain an internal "reference frame" by comparison to simulated behavior at a control plot. The model, in general, simulates substantial "natural" variation at the reference or control plots, both over time, due to sediment disturbance events in medium to high energy environments, and over space, due to geographically varying conditions, such as water depth and current regime.

Report↗

Insular and migrant species, longevity records, and new species records on Guana Island, British Virgin Islands

We conducted mist netting each October from 1994 to 2004 on Guana Island, British Virgin Islands, and recorded bird sightings to develop a more complete inventory of the island's resident and migrant species. During our study, we recorded four new species for the British Virgin Islands: Magnolia Warbler (Dendroica magnolia; 1996), Golden-winged Warbler (Vermivora chrysoptera; 1997), Swainson's Thrush (Catharus ustulatus; 2000), and Red-necked Phalarope (Phalaropus lobatus; 2004). Blackpoll Warbler (Dendroica striata) was the most frequently captured Neotropical migrant landbird, despite only being first detected in the region in 1989. Captures and detections of other Neotropical migrant landbirds suggest that many species may be more common in the region than previously believed, or, as speculated by other researchers, that migrant routes may be shifting eastward due to habitat degradation on western Caribbean islands. We also used recapture data to establish longevity records of resident species, including Caribbean Elaenia (Elaenia martinica; ??? 7 years), Bananaquit (Coereba flaveola; 7 years), Black-faced Grassquit (Tiaris bicolor; ???9 years), and Zenaida Dove (Zenaida aurita; 5 years). Longevities of other resident species were similar to, or slightly less than, those reported elsewhere.

Wilson Journal of Ornithology↗

The soil physics contributions of Edgar Buckingham

During 1902 to 1906 as a soil physicist at the USDA Bureau of Soils (BOS), Edgar Buckingham originated the concepts of matric potential, soil–water retention curves, specific water capacity, and unsaturated hydraulic conductivity ( K ) as a distinct property of a soil. He applied a formula equivalent to Darcy's law (though without specific mention of Darcy's work) to unsaturated flow. He also contributed significant research on quasi-empirical formulas for K as a function of water content, water flow in capillary crevices and in thin films, and scaling. Buckingham's work on gas flow in soils produced paradigms that are consistent with our current understanding. His work on evaporation elucidated the concept of self-mulching and produced sound and sometimes paradoxical generalizations concerning conditions that favor or retard evaporation. Largely overshadowing those achievements, however, is that he launched a theory, still accepted today, that could predict transient water content as a function of time and space. Recently discovered documents reveal some of the arguments Buckingham had with BOS officials, including the text of a two-paragraph conclusion of his famous 1907 report on soil water, and the official letter documenting rejection of that text. Strained interpersonal relations motivated the departure of Buckingham and other brilliant physicists (N.E. Dorsey, F.H. King, and Lyman Briggs) from the BOS during 1903 to 1906. Given that Buckingham and his BOS colleagues had been rapidly developing the means of quantifying unsaturated flow, these strained relations probably slowed the advancement of unsaturated flow theory.

Soil Science Society of America Journal↗

SICS: the Southern Inland and Coastal System interdisciplinary project of the USGS South Florida Ecosystem Program

State and Federal agencies are working jointly on structural modifications and improved water-delivery strategies to reestablish more natural surface-water flows through the Everglades wetlands and into Florida Bay. Changes in the magnitude, duration, timing, and distribution of inflows from the headwaters of the Taylor Slough and canal C-111 drainage basins have shifted the seasonal distribution and extent of wetland inundation, and also contributed to the development of hypersaline conditions in nearshore embayments of Florida Bay. Such changes are altering biological and vegetative communities in the wetlands and creating stresses on aquatic habitat. Affected biotic resources include federally listed species such as the Cape Sable seaside sparrow, American crocodile, wood stork, and roseate spoonbill. The U.S. Geological Survey (USGS) is synthesizing scientific findings from hydrologic process studies, collecting data to characterize the ecosystem properties and functions, and integrating the results of these efforts into a research tool and management model for this Southern Inland and Coastal System(SICS). Scientists from all four disciplinary divisions of the USGS, Biological Resources, Geology, National Mapping, and Water Resources are contributing to this interdisciplinary project.

Florida↗

Natural Hazards Science at the U.S. Geological Survey

The mission of the USGS in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. The USGS conducts hazard research and works closely with stakeholders and cooperators to inform a broad range of planning and response activities at individual, local, State, national, and international levels. It has critical statutory and nonstatutory roles regarding floods, earthquakes, tsunamis, landslides, coastal erosion, volcanic eruptions, wildfires, and magnetic storms. USGS science can help to understand and reduce risks from natural hazards by providing the information that decisionmakers need to determine which risk management activities are worth­while.

Fact Sheet↗

Water priorities for the nation—The U.S. Geological Survey next generation water observing system

The challenges of providing safe and sustainable water supplies for human and ecological uses and protecting lives and property during water emergencies are well recognized. The U.S. Geological Survey (USGS) plays an essential role in meeting these challenges through its observational networks and renowned water science and research activities (National Academies of Science, Engineering, and Medicine, 2018). Substantial advances in water science, together with emerging breakthroughs in technical and computational capabilities, have led the USGS to develop a Next Generation Water Observing System (NGWOS) . The NGWOS will provide real-time data on water quantity and quality in more affordable and rapid ways than previously possible, and in more locations. The data will be served through a modernized USGS National Water Information System that will be coupled to advanced modeling tools to inform daily water operations, decision-making during water emergencies (like floods, droughts, and contaminant spills), assessments of past trends in water quantity and quality, and forecasts of future water availability.

Fact Sheet↗

Fire patterns in the range of the greater sage-grouse, 1984-2013 - Implications for conservation and management

Fire ranks among the top three threats to the greater sage-grouse ( Centrocercus urophasianus ) throughout its range, and among the top two threats in the western part of its range. The national research strategy for this species and the recent U.S. Department of the Interior Secretarial Order 3336 call for science-based threats assessment of fire to inform conservation planning and fire management efforts. The cornerstone of such assessments is a clear understanding of where fires are occurring and what aspects of fire regimes may be shifting outside of their historical range of variation. This report fulfills this need by describing patterns of fire area, fire size, fire rotation, and fire season length and timing from 1984 to 2013 across the range of the greater sage-grouse. This information need is further addressed by evaluating the ecological and management implications of these fire patterns. Analyses are stratified by major vegetation types and the seven greater sage-grouse management zones, delineated regionally as four western and three eastern management zones. Soil temperature and moisture indicators of resilience to fire and resistance to cheatgrass invasion, and the potential for establishment of a grass/fire cycle, are used as unifying concepts in developing fire threat assessments for each analysis strata. The results indicate that fire threats are higher in the four western than in the three eastern management zones. Among the four western management zones, the Snake River Plain and the Columbia Basin ranked somewhat higher than the Southern Great Basin and Northern Great Basin in terms of fire effects on sage-grouse habitat. These results support the previous high ranking of fire as a threat to the greater sage-grouse in the western region. In contrast, considering the low rankings for fire threats in the eastern region, it may be useful to reconsider the relative importance of wildfire as a threat to greater sage-grouse in those three management zones.

California, Colorado, Idaho, Montana, Nevada, Oreg↗

Determining the distribution, status, and linkages of Agassiz's desert tortoise populations in the uplands surrounding the Coachella Valley

In support of the goals of the Coachella Valley Conservation Commission and the Bureau of Land Management, we performed surveys to determine the status, distribution, demographics, and possible genetic linkages of Agassiz’s desert tortoise (Gopherus agassizii) populations within the Coachella Valley Multiple Species Habitat Conservation Plan (CVMSHCP) area during a multi-decadal megadrought. Federal, state, and numerous parcels of privately owned conservation lands in the uplands around the periphery of the Coachella Valley were surveyed. Desert tortoise distribution data collected will be used to develop a species habitat model. These data will be overlaid with location data of flammable invasive plant species to inform fuels management and invasive plant control efforts in sensitive species habitat, as well as continue to identify high quality habitat and important desert tortoise linkage areas around the Coachella Valley. We also surveyed two established G. agassizii study plots – one at the Mesa Wind Energy Facility near Palm Springs, California and one at the Boyd Deep Canyon Desert Research Center. At those locations, we used resurveys and radio telemetry to assess habitat use, demography, and population status. We also used camera trapping at Deep Canyon to observe tortoise activities and behaviors in an unusual low elevation tortoise habitat.

California↗

USGS investigations of water produced during hydrocarbon reservoir development

Significant quantities of water are present in hydrocarbon reservoirs. When brought to the land surface during oil, gas, and coalbed methane production, the water&mdash;either naturally occurring or injected as a method to enhance production&mdash;is termed produced water. Produced water is currently managed through processes such as recycling, treatment and discharge, spreading on roads, evaporation or infiltration, and deep well injection. U.S. Geological Survey (USGS) scientists conduct research and publish data related to produced water, thus providing information and insight to scientists, decisionmakers, the energy industry, and the public. The information advances scientific knowledge, informs resource management decisions, and facilitates environmental protection. This fact sheet discusses integrated research being conducted by USGS scientists supported by programs in the Energy and Minerals and Environmental Health Mission Areas. The research products help inform decisions pertaining to understanding the nature and management of produced water in the United States.

Fact Sheet↗

Snake fungal disease: An emerging threat to wild snakes

Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused by Ophidiomyces ophiodiicola , a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts.

Philosophical Transactions of the Royal Society B:↗