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A global earthquake discrimination scheme to optimize ground-motion prediction equation selection

We present a new automatic earthquake discrimination procedure to determine in near-real time the tectonic regime and seismotectonic domain of an earthquake, its most likely source type, and the corresponding ground-motion prediction equation (GMPE) class to be used in the U.S. Geological Survey (USGS) Global ShakeMap system. This method makes use of the Flinn–Engdahl regionalization scheme, seismotectonic information (plate boundaries, global geology, seismicity catalogs, and regional and local studies), and the source parameters available from the USGS National Earthquake Information Center in the minutes following an earthquake to give the best estimation of the setting and mechanism of the event. Depending on the tectonic setting, additional criteria based on hypocentral depth, style of faulting, and regional seismicity may be applied. For subduction zones, these criteria include the use of focal mechanism information and detailed interface models to discriminate among outer-rise, upper-plate, interface, and intraslab seismicity. The scheme is validated against a large database of recent historical earthquakes. Though developed to assess GMPE selection in Global ShakeMap operations, we anticipate a variety of uses for this strategy, from real-time processing systems to any analysis involving tectonic classification of sources from seismic catalogs.

Bulletin of the Seismological Society of America↗

Well-Production Data and Gas-Reservoir Heterogeneity -- Reserve Growth Applications

Oil and gas well production parameters, including peakmonthly production (PMP), peak-consecutive-twelve month production (PYP), and cumulative production (CP), are tested as tools to quantify and understand the heterogeneity of reservoirs in fields where current monthly production is 10 percent or less of PMP. Variation coefficients, defined as VC= (F5-F95)/F50, where F5, F95, and F50 are the 5th, 95th, and 50th (median) fractiles of a probability distribution, are calculated for peak and cumulative production and examined with respect to internal consistency, type of production parameter, conventional versus unconventional accumulations, and reservoir depth. Well-production data for this study were compiled for 69 oil and gas fields in the Lower Pennsylvanian Morrow Formation of the Anadarko Basin, Oklahoma. Of these, 47 fields represent production from marine clastic facies. The Morrow data were supplemented by data from the Upper Cambrian and Lower Ordovician Arbuckle Group, Middle Ordovician Simpson Group, Middle Pennsylvanian Atoka Formation, and Silurian and Lower Devonian Hunton Group of the Anadarko Basin, one large gas field in Upper Cretaceous reservoirs of north-central Montana (Bowdoin field), and three areas of the Upper Devonian and Lower Mississippian Bakken Formation continuous-type (unconventional) oil accumulation in the Williston Basin, North Dakota and Montana. Production parameters (PMP, PYP, and CP) measure the net result of complex geologic, engineering, and economic processes. Our fundamental hypothesis is that well-production data provide information about subsurface heterogeneity in older fields that would be impossible to obtain using geologic techniques with smaller measurement scales such as petrographic, core, and well-log analysis. Results such as these indicate that quantitative measures of production rates and production volumes of wells, expressed as dimensionless variation coefficients, are potentially valuable tools for documenting reservoir heterogeneity in older fields for field redevelopment and risk analysis.

Bulletin↗

Utilizing hunter harvest effort to survey for wildlife disease: a case study of West Nile virus in greater sage-grouse

Greater sage-grouse ( Centrocercus urophasianus ; sage-grouse) are highly susceptible to infection with West Nile virus (WNV), with substantial mortality reported in wild populations and in experimentally infected birds. Although sage-grouse are hunted throughout much of their range, they have also recently been considered for protection under the Endangered Species Act. We used blood samples collected on filter-paper strips during the 2006–2010 Oregon, USA, annual sage-grouse hunt to survey for specific WNV-neutralizing antibodies that indicate a previous infection with WNV. During this period, hunters submitted 1,880 blood samples from sage-grouse they harvested. Samples obtained were proportional for all 12 Oregon sage-grouse hunting units. Laboratory testing of 1,839 samples by the WNV epitope-blocking enzyme-linked immunosorbent assay (bELISA) followed by plaque reduction neutralization test on bELISA-positive samples yielded 19 (1%) and 1 (0.05%) positive samples, respectively. These data provided early baseline information for future comparisons regarding the prevalence of WNV-specific neutralizing antibodies in sage-grouse in Oregon. This methodology may provide other states where sage-grouse (or other species) populations are hunted and where WNV constitutes a species conservation concern with a viable option to track the relative prevalence of the virus in populations.

Oregon↗

Simulation and mapping of soil-water conditions in the Great Plains

Soil-water conditions provide valuable insight into the hydrologic system in an area. A soil-water balance quantitatively summarizes soil-water conditions and is based on climatic, soil, and vegetation characteristics that vary spatially and temporally. Soil-water balances in the Great Plains of the central United States were simulated for 1951-1980. Results of the simulations were mean annual estimates of infiltration, runoff, actual evapotranspiration, potential recharge, and consumptive water and irrigation requirements at 152 climatic data stations. A method was developed using a geographic information system to integrate and map the simulation results on the basis of spatially variable climatic, soil, and vegetation characteristics. As an example, simulated mean annual potential recharge was mapped. Mean annual potential-recharge rates ranged from less than 0.5 inch in much of the north-central and southwestern Great Plains to more than 10 inches in parts of eastern Texas and southwestern Arkansas.

Water Resources Bulletin↗

Pressure coring a Gulf of Mexico deep-water turbidite gas hydrate reservoir: Initial results from The University of Texas–Gulf of Mexico 2-1 (UT-GOM2-1) Hydrate Pressure Coring Expedition

The University of Texas Hydrate Pressure Coring Expedition (UT-GOM2-1) recovered cores at near in situ formation pressures from a gas hydrate reservoir composed of sandy silt and clayey silt beds in Green Canyon Block 955 in the deep-water Gulf of Mexico. The expedition results are synthesized and linked to other detailed analyses presented in this volume. Millimeter- to meter-scale beds of sandy silt and clayey silt are interbedded on the levee of a turbidite channel. The hydrate saturation (the volume fraction of the pore space occupied by hydrate) in the sandy silts ranges from 79% to 93%, and there is little to no hydrate in the clayey silt. Gas from the hydrates is composed of nearly pure methane (99.99%) with less than 400 ppm of ethane or heavier hydrocarbons. The δ 13 C values from the methane are depleted (−60‰ to −65‰ Vienna Peedee belemnite), and it is interpreted that the gases were largely generated by primary microbial methanogenesis but that low concentrations of propane or heavier hydrocarbons record at least trace thermogenic components. The in situ pore-water salinity is very close to that of seawater. This suggests that the excess salinity generated during hydrate formation diffused away because the hydrate formed slowly or because it formed long ago. Because the sandy silt deposits have high hydrate concentration and high intrinsic permeability, they may represent a class of reservoir that can be economically developed. Results from this expedition will inform a new generation of reservoir simulation models that will illuminate how these reservoirs might be best produced.

Texas, Louisiana↗

Barcodes are a useful tool for labeling and tracking ecological samples

Barcodes are used to label and track just about everything these days. Look around your office, in your medicine cabinet, at the package you just received in the mail, or on the shelves of any shop in town, and you will immediately grasp the ubiquity of their use. Interestingly, railroads and supermarkets were the early pioneers of barcode development: the former needing a way to track railway car location and ownership on a national scale, the latter needing a way to track a diverse array of products and to decrease checkout times (Nelson 1997). Barcodes first came to use in the sciences via the field of medicine, and the medical literature contains hundreds of publications describing how this technology has reduced errors in patient specimen identification and handling, where error mitigation is crucial. In short, barcodes have been adopted by many industries, and in many fields they are now synonymous with asset tracking. In spite of their potential to efficiently organize “assets” (i.e., samples) and minimize human error, the use of barcodes has yet to gain widespread application in ecology. In an age where students take notes on laptops instead of paper, and where “text messaging” involves a smartphone rather than a ball‐point pen, why do otherwise tech‐savvy ecologists persist in hand‐labeling samples? Why do we repeatedly transcribe long and unique identifiers at each step in the process of sample analysis, thereby wasting time and creating opportunities for transcription errors and data loss? Why are most sample storage areas only successfully navigable by the lab manager who personally shelved the samples? In the case of our large ecology lab—and, we suspect, in many others as well—the answer to these questions was perpetually, “bar‐coding won't be worth the trouble.” Recently, however, we realized this was no longer a sufficient answer when we started a new research project that involved collecting an additional thousands of samples each year; we decided to embrace the tangible benefits of an electronic labeling system, and implemented barcoding in our lab. To be clear, the use of barcoding in ecology is not completely novel, and there have been early adopters of this technology. For example, the Cedar Creek Long Term Ecological Research (LTER) site has been using barcodes since at least the mid‐1990s to track the large number of samples collected in their long‐term experimental grasslands (T. A. Kennedy, personal observation ). Overall, however, Cedar Creek is an outlier: in informal e‐mail surveys of LTER sites, only two of eight respondents used barcodes for sample identification or tracking, and even then their use was generally limited to certain samples or certain stages of sample analysis. Our objective in this article is to use our lab as a case study to highlight the potential of barcodes to simplify numerous aspects of sample collection and processing.

Arizona↗

An automatic P‐Phase arrival‐time picker

Presented is a new approach for picking P ‐phase arrival time in single‐component acceleration or broadband velocity records without requiring detection interval or threshold settings. The algorithm P PHASE P ICKER transforms the signal into a response domain of a single‐degree‐of‐freedom (SDOF) oscillator with viscous damping and then tracks the rate of change of dissipated damping energy to pick P ‐wave phases. The SDOF oscillator has a short natural period and a correspondingly high resonant frequency, which is higher than most frequencies in a seismic wave. It also has a high damping ratio (60% of critical). At this damping level, the frequency response approaches the Butterworth maximally flat magnitude filter, and phase angles are preserved. The relative input energy imparted to the oscillator by the input signal is converted to elastic strain energy and then dissipated by the damping element as damping energy. The damping energy yields a smooth envelope over time; it is zero in the beginning of the signal, zero or near zero before the P ‐phase arrival, and builds up rapidly with the P wave. Because the damping energy function changes considerably at the onset of the P wave, it is used as a metric to track and pick the P ‐phase arrival time. The P PHASE P ICKER detects P ‐phase onset using the histogram method. Its performance is compared with picking techniques using short‐term‐average to long‐term‐average ratio, and a picking method that finds the first P ‐phase arrival time using the Akaike information criterion. A large set of records with various intensities and signal‐to‐noise ratios is used for testing the P PHASE P ICKER , and it is demonstrated that P PHASE P ICKER is able to more accurately pick the onset of genuine signals against the background noise and to correctly distinguish between whether the first arrival is a P wave (emergent or impulsive) or whether the signal is from a faulty sensor.

Bulletin of the Seismological Society of America↗

Rim Sim: A Role-Play Simulation

Rim Sim is a 6-hour, eight-party negotiation that focuses on creating a framework for the long-term disaster-recovery efforts. It involves a range of players from five countries affected by two natural disasters: a typhoon about a year ago and an earthquake about 6 months ago. The players are members of an International Disaster Working Group (IDWG) that has been created by an international commission. The IDWG has been charged with drawing up a framework for managing two issues: the reconstruction of regionally significant infrastructure and the design of a mechanism for allocating funding to each country for reconstruction of local infrastructure and ongoing humanitarian needs. The first issue will involve making choices among five options (two harbor options, two airport options, and one rail-line option), each of which will have three levels at which to rebuild. The second issue will involve five starting-point options. Participants are encouraged to invent other options for both issues. The goal of Rim Sim is to raise questions about traditional approaches to disaster-preparedness planning and reconstruction efforts in an international setting, in this case the Pacific Rim. Players must confront the reverberating effects of disasters and the problems of using science and technical information in decisionmaking, and are introduced to a consensus-building approach emphasizing face-to-face dialog and multinational cooperation in dealing with humanitarian concerns, as well as long-term efforts to reconstruct local and regional infrastructure. The Rim Sim simulation raises four key points: ripple effects of disasters, role of science, multiparty negotiation, and building personal relationships.

Bulletin↗

Bibliography and index of U.S. Geological Survey trace elements and related reports through June 1956

This bibliography supersedes TEI-500, "U. S. Geological Survey Trace Elements and related reports through 1954." Part I is a numerical list of U. S. Geological Survey Trace Elements Investigations and Memorandum reports. This part lists reports that have been transmitted to the U. S. Atomic Energy Comission and also reports in preparation (followed by an asterisk) for which tentative titles were available on June 30, 1956. If a report or part of a report has been published, the fact is indicated by the abbreviation of the medium of publication. (See also Part II.) Part II is a reference guide to Trace Elements and related reports that are available to the public. (Part II supersedes Part I of Bulletin 1019-B.) These reports are grouped according to type of publication or release. If a report or part of a report has been published in more than one form, corss-references indicate the other forms of publication. Publications in preparation or in press on June 30, 1956, are designated by an asterisk. Part III is an author index. The words "with" and "and" are used to indicate seniority of authorship. For example, a listing of Black and White indicates that Black is the senior author. A listing of Black with White indicates that White is the senior author. Part IV is an index for finding reports on specific areas or subjects. Information for the index was taken from titles, tables of contents, and abstracts of unpublished reports and from titles of published reports. The index in TEI-500 was used as a guide.

Trace Elements Investigations↗

Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep ( Ovis canadensis ), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae , Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi (median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimia spp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Wildlife Society Bulletin↗

White-tailed deer age ratios as herd management and predator impact measures in Pennsylvania

A review of the Pennsylvania Game Commission's (PGC) deer management program and public concern about predator impacts on deer ( Odocoileus virginianus ) populations compelled the PGC to investigate the role of age ratios in developing management recommendations. Age ratios, such as proportion of juveniles in the antlerless harvest, may provide an index to population productivity and predator impacts. We estimated proportion of juveniles in the antlerless harvest from hunter-killed deer, population trends using the Pennsylvania (USA) sex–age–kill model, and reproduction from road-killed females. Using these estimates and a simulation model, we concluded that no single age-ratio value would serve as a reliable measure of population status. Wildlife Management Unit-specific trends in proportion of juveniles in the antlerless harvest and population trends provided the most relevant management information. We also provide an example decision chart to guide management actions in response to declining age ratios in the harvest. Although predator management activities and juvenile survival studies are often desired by the public, our decision-chart example indicated a number of deer management options exist before investing resources in predator management activities and juvenile survival studies.

Pennsylvannia↗

Deposits of Claiborne and Jackson age in Georgia

In 1911 the Geological Survey of Georgia published as Bulletin 26 a "Preliminary report on the geology of the Coastal Plain of Georgia," by Otto Veatch and Lloyd William Stephenson, prepared in cooperation with the United States Geological Survey under the supervision of T. Wayland Vaughan, a geologist in charge of Coastal Plain investigations, who contributed the determinations of the invertebrate fossils of the Tertiary and Quaternary formations. Although this report constituted a decided advance in our knowledge of the geology of the Coastal Plain of Georgia, it was admittedly of reconnaissance character, and corrections and additions to it were to be expected. During the last few years field work has been prosecuted vigorously in the Coastal Plain of Georgia, and the additional information thus accumulated throws light upon certain problems of stratigraphy left unsolved by Veatch and Stephenson and alters considerably some of their correlations. The object of the present paper is to present the new evidence regarding the age and correlation of the Eocene formations of Georgia and to revise in accordance with present knowledge the descriptions of the deposits of Claiborne and Jackson age.

Georgia↗

High latitude meteoric δ 18 O compositions: Paleosol siderite in the Middle Cretaceous Nanushuk Formation, North Slope, Alaska

Siderite-bearing pedogenic horizons of the Nanushuk Formation of the North Slope, Alaska, provide a critical high paleolatitude oxygen isotopic proxy record of paleoprecipitation, supplying important empirical data needed for paleoclimatic reconstructions and models of "greenhouse-world" precipitation rates. Siderite ??18O values were determined from four paleosol horizons in the National Petroleum Reserve Alaska (NPR-A) Grandstand # 1 Core, and the values range between -17.6??? and -14.3??? Peedee belemnite (PDB) with standard deviations generally less than 0.6??? within individual horizons. The ??13C values are much more variable, ranging from -4.6??? to +10.8??? PDB. A covariant ??18O versus ??13C trend in one horizon probably resulted from mixing between modified marine and meteoric phreatic fluids during siderite precipitation. Groundwater values calculated from siderite oxygen isotopic values and paleobotanical temperature estimates range from -23.0??? to -19.5??? standard mean ocean water (SMOW). Minor element analyses show that the siderites are impure, having enrichments in Ca, Mg, Mn, and Sr. Minor element substitutions and Mg/Fe and Mg/ (Ca + Mg) ratios also suggest the influence of marine fluids upon siderite precipitation. The pedogenic horizons are characterized by gleyed colors, rare root traces, abundant siderite, abundant organic matter, rare clay and silty clay coatings and infillings, some preservation of primary sedimentary stratification, and a lack of ferruginous oxides and mottles. The pedogenic features suggest that these were poorly drained, reducing, hydromorphic soils that developed in coal-bearing delta plain facies and are similar to modern Inceptisols. Model-derived estimates of precipitation rates for the Late Albian of the North Slope, Alaska (485-626 mm/yr), are consistent with precipitation rates necessary to maintain modern peat-forming environments. This information reinforces the mutual consistency between empirical paleotemperature estimates and isotope mass balance models of the hydrologic cycle and can be used in future global circulation modeling (GCM) experiments of "greenhouse-world" climates to constrain high latitude precipitation rates in simulations of ancient worlds with decreased equator-to-pole temperature gradients. ?? 2004 Geological Society of America.

Geological Society of America Bulletin↗

Kirtland's warblers on the nesting grounds during the post- breeding period

Information indicates that a substantial number of breeding birds remain in Michigan through September, and a few individuals probably remain into early October. Migration apparently consists of two waves of migrants: an early departure (mid-August to early September); and late departure (late September). Based on our findings, we recommend that major Kirtland's warbler areas be kept closed into mid-September.

The Wilson Bulletin↗

Comparisons of two moments‐based estimators that utilize historical and paleoflood data for the log Pearson type III distribution

The expected moments algorithm (EMA) [ Cohn et al. , 1997 ] and the Bulletin 17B [ Interagency Committee on Water Data , 1982 ] historical weighting procedure (B17H) for the log Pearson type III distribution are compared by Monte Carlo computer simulation for cases in which historical and/or paleoflood data are available. The relative performance of the estimators was explored for three cases: fixed‐threshold exceedances, a fixed number of large floods, and floods generated from a different parent distribution. EMA can effectively incorporate four types of historical and paleoflood data: floods where the discharge is explicitly known, unknown discharges below a single threshold, floods with unknown discharge that exceed some level, and floods with discharges described in a range. The B17H estimator can utilize only the first two types of historical information. Including historical/paleoflood data in the simulation experiments significantly improved the quantile estimates in terms of mean square error and bias relative to using gage data alone. EMA performed significantly better than B17H in nearly all cases considered. B17H performed as well as EMA for estimating X 100 in some limited fixed‐threshold exceedance cases. EMA performed comparatively much better in other fixed‐threshold situations, for the single large flood case, and in cases when estimating extreme floods equal to or greater than X 500 . B17H did not fully utilize historical information when the historical period exceeded 200 years. Robustness studies using GEV‐simulated data confirmed that EMA performed better than B17H. Overall, EMA is preferred to B17H when historical and paleoflood data are available for flood frequency analysis.

Water Resources Research↗

Declines of greater and lesser scaup populations: issues, hypotheses, and research needs

The population estimate for greater (Aythya marila) and lesser (Aythya affinis) scaup (combined) has declined dramatically since the early 1980s to record lows in 1998. The 1998 estimate of 3.47 million scaup is far below the goal of 6.3 million set in the North American Waterfowl Management Plan (NAWMP), causing concern among biologists and hunters. We summarize issues of concern, hypotheses for factors contributing to the population decline, and research and management needs recommended by participants of the Scaup Workshop, held in September 1999. We believe that contaminants, lower female survival, and reduced recruitment due to changes in food resources or breeding-ground habitats are primary factors contributing to the decline. These factors are not mutually exclusive but likely interact across seasons. Workshop participants identified seven action items. We need to further delineate where declines in breeding populations have occurred, with a primary focus on the western Canadian boreal forest, where declines appear to be most pronounced. Productivity in various areas and habitats throughout the breeding range needs to be assessed by conducting retrospective analyses of existing data and by intensive field studies at broad and local scales. Annual and seasonal survival rates need to be determined in order to assess the role of harvest or natural mortality. Effects of contaminants on reproduction, female body condition, and behavior must be investigated. Use, distribution, and role of food resources relative to body condition and reproduction need to be examined to better understand seasonal dynamics of nutrient reserves and the role in reproductive success. Affiliations among breeding, migration, and wintering areas must be assessed in order to understand differential exposure to harvest or contaminants, and differential reproductive success and recruitment. Biologists and agencies need to gather and improve information needed to manage greater and lesser scaup separately; this includes monitoring the breeding populations of each species separately, closer examination of existing data to improve surveys and data collection, and re-evaluation of the NAWMP population goal. These complex issues will require extensive cooperation and communication among many agencies and organizations in North America.

Wildlife Society Bulletin↗

Declining scaup populations: issues, hypotheses, and research needs

The population estimate for greater (Aythya marila) and lesser (Aythya affinis) scaup (combined) has declined dramatically since the early 1980s to record lows in 1998. The 1998 estimate of 3.47 million scaup is far below the goal of 6.3 million set in the North American Waterfowl Management Plan (NAWMP), causing concern among biologists and hunters. We summarize issuesof concern, hypotheses for factors contributing to the population decline, and research and management needs recommended by participants of the Scaup Workshop, held in September 1999. We believe that contaminants, lower female survival, and reduced recruitment due to changes in food resources or breedingground habitats are primary factors contributing to the decline. These factors are not mutually exclusive but likely interact across seasons. Workshop participants identified seven action items. We need to further delineate where declines in breeding populations have occurred, with a primary focus on the western Canadian boreal forest, where declines appear to be most pronounced. Productivity in various areas and habitats throughout the breeding range needs to be assessed by conducting retrospective analyses of existing data and by intensive field studies at broad and local scales. Annual and seasonal survival rates need to be determined in order to assess the role of harvest or natural mortality. Effects of contaminants on reproduction, female body condition, and behavior must be investigated. Use, distribution, and role of food resources relative to body condition and reproduction need to be examined to better understand seasonal dynamics of nutrient reserves and the role in reproductive success. Affiliations among breeding, migration, and wintering areas must be assessed in order to understand differential exposure to harvest or contaminants, and differential reproductive success and recruitment. Biologists and agencies need to gather and improve information needed to manage greater and lesser scaup separately; this includes monitoring the breeding populations of each species separately, closer examination of existing data to improve surveys and data collection, and re-evaluation of the NAWMP population goal. These complex issues will require extensive cooperation and communication among many agencies and organizations in North America.

Wildlife Society Bulletin↗

Raptor electrocution on power lines: Current issues and outlook

Electrocution on power lines is one of many human-caused mortality factors that affect raptors. Cost-effective and relatively simple raptor-safe standards for power line modification and construction have been available for over 25 years. During the 1970s and early 1980s, electric industry efforts to reduce raptor electrocutions were very coordinated and proactive, but predictions about resolving the problem were overly optimistic. Today, raptors continue to be electrocuted, possibly in large numbers. The electrocution problem has not been resolved, partly because of the sheer number of potentially lethal power poles in use and partly because electrocution risks may be more pervasive and sometimes less conspicuous than once believed. Also, responses to the problem by individual utilities have not been uniform, and deregulation of the electric industry during the 1990s may have deflected attention from electrocution issues. To control raptor electrocutions in the future, the industry must increase information sharing and technology transfer, increase efforts to retrofit lethal power poles, and above all ensure that every new and replacement line constructed incorporates raptor-safe standards at all phases of development. Finally, responsibility for the electrocution problem must be shared. Federal, state, and local governments, academic institutions, the conservation community, and the consumer all can play critical roles in an effort that will, by necessity, extend well into the new century.

Wildlife Society Bulletin↗