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Trichomonas gypaetinii was detected in 117 (88%) of 133 Bald Eagles (Haliaeetus leucocephalus) and in 0/7 Golden Eagles (Aquila chrysaetos) in the USA, with no sex or age prevalence difference. All eagles lacked associated lesions. This study indicated that T. gypaetinii is common and widespread in Bald Eagles, but rarely associated with disease., (© Wildlife Disease Association 2024.)

A previously published model of avian electrocution risk, the "2014 model," compared power poles that electrocuted birds (electrocution poles; including 21 golden eagle Aquila chrysaetos electrocutions) with poles not known to have electrocuted birds (comparison poles). The 2014 model produces pole-specific risk index scores between 0 and 1. The scores rank relative risk so electric utilities can maximize conservation benefits per dollar spent by focusing retrofitting on poles with greatest risk. Although the creation of the 2014 model encompassed a study population of birds and poles in southern California, the 2014 model has potential for use in managing a target population of raptors including golden eagles throughout the western United States. Use beyond southern California is only appropriate if the study population is similar enough to the target population for the 2014 model to predict risk effectively. To evaluate similarity, we examined five sources of evidence: 1) the relative consistency in electrical safety codes for power poles; 2) the body sizes of golden eagles in the study and target populations; and consistency in structure-specific factors associated with 3) golden eagle electrocutions in other studies, 4) other avian electrocutions, and 5) previously unreported golden eagle electrocutions. We found that although the study population in the 2014 model included relatively few golden eagles, data were sufficient to create a model that is applicable to a target population throughout the western United States. The model also can be useful in helping determine equivalencies between pole types if utilities seek to compare benefits of retrofitting small numbers of high-risk poles with large numbers of low-risk poles. [ABSTRACT FROM AUTHOR]

Bald eagles (Haliaeetus leucocephalus) are considered a recovery success in the United States after rebounding from near extirpation due to widespread use of the insecticide dichlorodiphenyltrichloroethane (DDT) in the twentieth century. Although abundances of bald eagles have increased since DDT was banned, other contaminants have remained in the environment with unknown influence on eagle population trends. Ingestion of spent lead (Pb) ammunition, the source of Pb most available to eagles and other scavengers in the United States, is known to kill individual eagles, but the influence of the contaminant on overall population dynamics remains unclear, resulting in longstanding controversy over the continued legality of the use of Pb in terrestrial hunting ammunition. We hypothesized that mortalities from the ingestion of Pb reduced the long‐term growth rate and resiliency of bald eagles in the northeast United States over the last 3 decades. We used Holling's definition of resilience (the ability of a system to absorb changes of state variables, driving variables, and parameters and still persist) to quantify how reduction in survival from Pb‐associated mortalities reduced the likelihood of population persistence. We used a population matrix model and necropsy records gathered between 1990 and 2018 from a 7‐state area to compare population dynamics under current versus hypothetical Pb‐reduced and Pb‐free scenarios. Despite a robust increase in eagle abundances in the northeast United States over that period, we estimated that deaths arising from ingestion of Pb was associated with a 4.2% (females) and 6.3% (males) reduction in the asymptotic long‐term growth rate (lambda). Comparison between real (current) and counterfactual (Pb‐reduced and Pb‐free) population dynamics indicated that the deaths from acute Pb poisoning were additive because the mortality events were associated with marked reduction in annual survival performance of hatchlings and reproductive females. These shifts in survival performance were further associated with a reduction in resilience for hatchling (95.4%) and breeding (81.6%) female eagles. Counterintuitively, the current conditions produced an increase in resilience (68.9%) for immature and non‐breeding female eagles over hypothetical Pb‐free conditions, suggesting that the population of eagles in the northeast United States reorganized (in a population dynamics sense) to ensure population expansion despite additive mortalities associated with Pb. This study can be used by state and federal wildlife managers or non‐governmental organizations to inform policy surrounding the use of lead ammunition or to educate hunters on the population‐scale effects of their ammunition choices. [ABSTRACT FROM AUTHOR]

Effectively managing take of wildlife resulting from human activities poses a major challenge for applied conservation. Demographic data essential to decisions regarding take are often expensive to collect and are either not available or based on limited studies for many species. Therefore, modeling approaches that efficiently integrate available information are important to improving the scientific basis for sustainable take thresholds. We used the prescribed take level (PTL) framework to estimate allowable take for bald eagles (Haliaeetus leucocephalus) in the conterminous United States. We developed an integrated population model (IPM) that incorporates multiple sources of information and then use the model output as the scientific basis for components of the PTL framework. Our IPM is structured to identify key parameters needed for the PTL and to quantify uncertainties in those parameters at the scale at which the United States Fish and Wildlife Service manages take. Our IPM indicated that mean survival of birds >1 year old was high and precise (0.91, 95% CI = 0.90–0.92), whereas mean survival of first‐year eagles was lower and more variable (0.69, 95% CI = 0.62–0.78). We assumed that density dependence influenced recruitment by affecting the probability of breeding, which was highly imprecise and estimated to have declined from approximately 0.988 (95% CI = 0.985–0.993) to 0.66 (95% CI = 0.34–0.99) between 1994 and 2018. We sampled values from the posterior distributions of the IPM for use in the PTL and estimated that allowable take (e.g., permitted take for energy development, incidental collisions with human made structures, or removal of nests for development) ranged from approximately 12,000 to 20,000 individual eagles depending on risk tolerance and form of density dependence at the scale of the conterminous United States excluding the Southwest. Model‐based thresholds for allowable take can be inaccurate if the assumptions of the underlying framework are not met, if the influence of permitted take is under‐estimated, or if undetected population declines occur from other sources. Continued monitoring and use of the IPM and PTL frameworks to identify key uncertainties in bald eagle population dynamics and management of allowable take can mitigate this potential bias, especially where improved information could reduce the risk of permitting non‐sustainable take. [ABSTRACT FROM AUTHOR]

In order to contribute to conservation planning efforts for golden eagles (Aquila chrysaetos) in the western U.S., we developed nest site models using >6,500 nest site locations throughout a >3,483,000 km2 area of the western U.S. We developed models for twelve discrete modeling regions, and estimated relative density of nest sites for each region. Cross-validation showed that, in general, models accurately estimated relative nest site densities within regions and sub-regions. Areas estimated to have the highest densities of breeding golden eagles had from 132–2,660 times greater densities compared to the lowest density areas. Observed nest site densities were very similar to those reported from published studies. Large extents of each modeling region consisted of low predicted nest site density, while a small percentage of each modeling region contained disproportionately high nest site density. For example, we estimated that areas with relative nest density values <0.3 represented from 62.8–97.8% ( = 82.5%) of each modeling area, and those areas contained from 14.7–30.0% ( = 22.1%) of the nest sites. In contrast, areas with relative nest density values >0.5 represented from 1.0–12.8% ( = 6.3%) of modeling areas, and those areas contained from 47.7–66.9% ( = 57.3%) of the nest sites. Our findings have direct application to: 1) large-scale conservation planning efforts, 2) risk analyses for land-use proposals such as recreational trails or wind power development, and 3) identifying mitigation areas to offset the impacts of human disturbance. [ABSTRACT FROM AUTHOR]

Recreational ground squirrel shooting is a popular activity throughout the western United States and serves as a tool for managing ground squirrel populations in agricultural regions. Belding’s ground squirrels (Spermophilus beldingi) are routinely shot in California, Nevada, and Oregon across habitats that overlap with breeding avian scavengers. Ground squirrels shot with lead (Pb)-based bullets may pose a risk to avian scavengers if they consume carcasses containing Pb fragments. To assess the potential risk to breeding avian scavengers we developed a model to estimate the number, mass, and distribution of Pb fragments in shot ground squirrels using radiographic images. Eighty percent of shot carcasses contained detectible Pb fragments with an average of 38.6 mg of Pb fragments. Seven percent of all carcasses contained Pb fragment masses exceeding a lethal dose for a model raptor nestling (e.g. American kestrel Falco sparverius). Bullet type did not influence the number of fragments in shot ground squirrels, but did influence the mass of fragments retained. Belding’s ground squirrels shot with .17 Super Mag and unknown ammunition types contained over 28 and 17 times more mass of Pb fragments than those shot with .22 solid and .22 hollow point bullets, respectively. Ground squirrel body mass was positively correlated with both the number and mass of Pb fragments in carcasses, increasing on average by 76% and 56% respectively across the range of carcass masses. Although the mass of Pb retained in ground squirrel carcasses was small relative to the original bullet mass, avian scavenger nestlings that frequently consume shot ground squirrels may be at risk for Pb-induced effects (e.g., physiology, growth, or survival). Using modeling efforts we found that if nestling golden eagles (Aquila chrysaetos), red-tailed hawks (Buteo jamaicensis), and Swainson’s hawks (B. swainsoni) consumed shot ground squirrels proportionately to the nestling’s mass, energy needs, and diet, 100% of the nestling period would exceed a 50% reduction in delta-aminolevulinic acid dehydratase production threshold, the last 13–27% of the nestling stage would exceed a reduced growth rate threshold, but no nestlings would be expected to exceed a level of Pb ingestion that would be lethal. [ABSTRACT FROM AUTHOR]

The Bald and Golden Eagle Protection Act prohibits the taking or possession of eagles and eagle parts. Recognizing the centrality of eagles in many Native American religions, Congress carved out an exception to that prohibition for "the religious purposes of Indian tribes." The problems with the administration of that exception are reaching crisis proportions. At the Fish and Wildlife Service's National Eagle Repository, which collects dead eagles from around the country and distributes them to members of federally recognized Indian tribes, more than six thousand tribal members are on a waiting list for eagles. That list grows each year. Frustration with the current system feeds a burgeoning black market that threatens the viability of eagle populations. Neither of the Eagle Act's goals is being met: eagles are not adequately protected, and tribal religious needs are not satisfied. Scholarship in this area has neither fully elucidated the cross-cutting tensions in the administration of the Eagle Act nor prescribed a realistic solution. This Article fills that gap. First, the Article examines a series of tensions: between species preservation and religious freedom; between accommodating the religious needs of tribal members and not accommodating others with the same religious needs; within the case law itself; and between the government's effort to accommodate tribal religion and the deep dissatisfaction of the tribal community. This Article then proposes a solution: changing the Fish and Wildlife Service's administration of the exception from permitting individuals to permitting tribes and ultimately turning over much of the administration of the Indian tribes exception to the tribes acting collectively. The Article explains how scholarship on indigenous cultural property, community property solutions to the tragedy of the commons, and tribal self-determination supports this proposal. Finally, the Article shows how this proposal will alleviate some of the tension in the administration of the Eagle Act's Indian tribes exception. [ABSTRACT FROM AUTHOR]

Background: During the coronavirus disease-2019 (COVID-19) pandemic cumulative United States COVID-19 deaths per capita were higher than all other large, high-income nations, but with substantial variation across the country., Objective: The aim was to detail the public health response during the pandemic in Eagle County, Colorado., Research Design and Measures: Observational study using pre-COVID-19 county public health metrics. Pandemic actions were recorded from a narrative summary of daily phone consultations by a county-wide taskforce and interviews. Outcomes obtained from local, state, and nationally reported databases., Methods: Eagle County began with a life expectancy of 85.9, low all-cause age-adjusted death rates equal for both White and Latinx populations, a high household median income, and other prepandemic advantages. It also launched an innovative, independent county-wide taskforce lead by experienced mid-level managers. The taskforce implemented rapid communication of decision consequences, made immediate course corrections without traditional organizational approvals or contradictory political pressures., Results: Eagle County was first in Colorado to obtain Personal Protective Equipment and to establish a drive-through testing facility. The COVID-19 case fatality rate was 0.34%. The sole intensive care unit never reached maximum capacity. By March 2022, Eagle County had administered at least 1 vaccine dose to 100% of the population and 83% were fully vaccinated., Conclusions: It is not possible to directly attribute superior outcomes to either the baseline characteristics of Eagle County or its innovative taskforce design and deployment. Rather this report highlights the potential impact that improving the baseline health status of US citizens and permitting novel problem-solving approaches by local public health officials might have for the next pandemic., Competing Interests: S.K. was, and C.L. is an employee respectively of Vail Health. W.A.K. declares no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)

In 2016, the then US President Barack Obama announced the Cancer Moonshot with a view to making 10 years' worth of progress in cancer prevention, diagnosis and treatment in only 5 years. This Perspective evaluates the FDA approvals of therapeutic agents for use in solid tumour oncology for the period 2017-2021 against the aspirations of the Cancer Moonshot. In the past 5 years, the FDA issued an unprecedented 161 new approvals of therapeutic agents for various indications in adult patients with solid tumours. However, less than a third (27%) of the newly approved medicines are supported by unequivocal evidence of an overall survival benefit; most are supported by positive signals from surrogate end points. Herein, the European Society for Medical Oncology Magnitude of Clinical Benefit Scale version 1.1 was used to evaluate the clinical value of the therapies granted FDA approval during the period 2017-2021. The results of this appraisal indicate a low level of clinical benefit for a substantial proportion (~20%) of the new indications, with most (~44%) providing intermediate benefit. The data suggest that, beyond increases in the sheer quantity of approvals, considerable improvement in the quality of the approved treatments is required to more confidently ensure that the clinical benefits are real and substantial enough to clearly justify the risks to patients., (© 2022. Springer Nature Limited.)

To determine risk factors and seasonal trends of lead poisoning in bald (Haliaeetus leucocephalus) and golden (Aquila chrysaetos) eagles, blood lead levels were evaluated in eagles admitted from the inland Pacific Northwest region of the United States to the Raptor Rehabilitation Program, College of Veterinary Medicine at Washington State University from 1991 to 2008. Admissions were from Washington (32 bald eagles, 27 golden eagles), northern Idaho (21 bald eagles, 25 golden eagles), northeastern Oregon (5 bald eagles, 6 golden eagles), Montana (2 bald eagles), Alaska (I bald eagle), and unrecorded (6 bald eagles, 5 golden eagles). In these birds, 48% (22/46) of bald and 62% (31/50) of golden eagles tested had blood lead levels considered toxic by current standards. Of the bald and golden eagles with toxic lead levels, 91% (20/22) and 58% (18/31) respectively, were admitted after the. end of the general deer and elk hunting seasons in December. Coyote hunting intensifies with the end of the large game hunting seasons and coyote carcasses left in the field and contaminated with lead bullet fragments become readily available food sources, exposing scavenging bald and golden eagles to high risk of acute lead poisoning. [ABSTRACT FROM AUTHOR]

The article presents a study, which has used band recovery data for evaluating distances between locations of recovery for 154 nestling Florida Bald Eagles while discussing the understanding natal dispersal implications and the philopatry among the species. It has been observed that female and younger birds in particular, had longer distances for recovery among the 21 mature eagles of known banding and sex. The study suggests that the records being examined show higher level of philopatry as well as short distances for natal dispersal specifically in male Bald Eagles.

The article focuses on the implications of the Tenth Circuit Court of Appeals' United States v. Friday opinion for the future of Native American religious challenges to the Bald and Golden Eagle Protection Act (BGEPA) in the U.S. It offers a brief historical analysis of the BGEPA and the relevant statutory provisions such as the exception that allows Native Americans to apply for eagle take permits. The development of the Religious Freedom and Restoration Act of 1993 (RFRA) is cited.

Since 1940, Native Americans have been required to apply to the United States Fish and Wildlife Service (USFWS) to obtain eagle carcasses or other parts. An increase in tribal populations and a revitalization of cultural practices has increased the demand for eagle parts and led to delays in filling requests. In a cooperative effort with the USFWS, the Pueblo of Zuni Indian Tribe recently revived the ancient Zuni practice of live eagle husbandry in order to both maintain this cultural practice and make eagle feathers more widely available to tribal members. This is being accomplished in a manner consistent with modern raptor husbandry techniques, but in a Zuni-based context. Environmental professionals have assisted the project greatly, especially concerning the life history and behavioral needs of the birds and the implications for eagle conservation. Although we have explored and decided against the idea of breeding captive eagles so that their young may be released into the wild (because it goes against traditional Zuni beliefs), this is certainly a feasible option for other, similar facilities and would be strongly supported by the USFWS, conservation groups, and wildlife professionals. [ABSTRACT FROM AUTHOR]

Deals with a study which identified the extinct Hawaiian eagle or Haliaeetus by obtaining mitochondrial DNA sequences from its bones. Methods used in the study; Similarities of the DNA sequences of the Haliaeetus to the White-tailed eagle.

Provides information on a study which examined the autumn stopover behavior of Bald Eagles that migrate by soaring, at Hauser Reservoir, Montana from 1992 to 1994. Methods used; Results; Correlation of the body condition of Bald Eagles with date of capture and post capture residence time.

In the United States, the Bald and Golden Eagle Protection Act prohibits take of golden eagles (Aquila chrysaetos) unless authorized by permit, and stipulates that all permitted take must be sustainable. Golden eagles are unintentionally killed in conjunction with many lawful activities (e.g., electrocution on power poles, collision with wind turbines). Managers who issue permits for incidental take of golden eagles must determine allowable take levels and manage permitted take accordingly. To aid managers in making these decisions in the western United States, we used an integrated population model to obtain estimates of golden eagle vital rates and population size, and then used those estimates in a prescribed take level (PTL) model to estimate the allowable take level. Estimated mean annual survival rates for golden eagles ranged from 0.70 (95% credible interval = 0.66-0.74) for first-year birds to 0.90 (0.88-0.91) for adults. Models suggested a high proportion of adult female golden eagles attempted to breed and breeding pairs fledged a mean of 0.53 (0.39-0.72) young annually. Population size in the coterminous western United States has averaged ~31,800 individuals for several decades, with λ = 1.0 (0.96-1.05). The PTL model estimated a median allowable take limit of ~2227 (708-4182) individuals annually given a management objective of maintaining a stable population. We estimate that take averaged 2572 out of 4373 (59%) deaths annually, based on a representative sample of transmitter-tagged golden eagles. For the subset of golden eagles that were recovered and a cause of death determined, anthropogenic mortality accounted for an average of 74% of deaths after their first year; leading forms of take over all age classes were shooting (~670 per year), collisions (~611), electrocutions (~506), and poisoning (~427). Although observed take overlapped the credible interval of our allowable take estimate and the population overall has been stable, our findings indicate that additional take, unless mitigated for, may not be sustainable. Our analysis demonstrates the utility of the joint application of integrated population and prescribed take level models to management of incidental take of a protected species., (© 2022 The Authors. Ecological Applications published by Wiley Periodicals LLC on behalf of The Ecological Society of America. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Published research on the health status of wild bald eagles ( Haliaeetus leucocephalus ) in Eastern Canada is limited. This study examined the health status of 53 nestling bald eagles on Prince Edward Island in the summers of 2012 and 2013, including biochemistry reference intervals, a summary of hematological parameters, and background lead accumulation. Baseline lead levels of greater than 0.02 ppm were noted in nine nestlings, and the odds of lead accumulation decreased with increased weight and body condition score. Biochemical reference intervals were developed using a method outlined by the American Society of Veterinary Clinical Pathology. These intervals can vary between populations based on age and geographic area. These findings will therefore be useful in further research and clinical cases within this population, as well as further research into subclinical lead accumulation in growing raptors.

The article reports the decision of the U.S. Court of Appeals for the Fifth Circuit in the case "Mc Allen Grace Brethren Church v. Salazar." The court held that the government does not satisfy the scrutiny test under the Religious Freedom Restoration Act if it does not produce evidence that it is using the restrictive means in enforcing the Migratory Bird Treaty Act and the Bald & Golden Eagle Protection Act against non-federally recognized tribes who use eagle feathers for religious purposes.

Wildlife and human health are at risk of lead exposure from spent hunting ammunition. Lead exposure persists for bald eagles due to bullet fragments in game animal gut piles and unretrieved carcasses, and is also a human health risk when wild game is procured using lead ammunition. Programs encouraging the voluntary use of nonlead ammunition have become a popular approach mitigating these effects. This study explored attitudes and experiences of United States Fish and Wildlife Service (USFWS) staff implementing an outreach program encouraging deer hunters to voluntary use nonlead ammunition on 54 National Wildlife Refuges (NWRs) in the Upper Midwest, U.S. to understand factors affecting program implementation. We conducted 29 semi-structured interviews of USFWS staff along with 60 responses from an open-ended survey question. Twelve themes emerged from the data and were grouped into three broad categories: (1) challenges of dealing with complex issues, (2) importance of messengers and messages, and (3) resistance from staff. Challenges of dealing with complex issues included administrative restraint and uncertainty, scope and scale of program, human health not an agency responsibility, contextual political influences, and public-private collaborations. Importance of messengers and messages included the importance of experience, and salience of human health risk. Finally, resistance from staff included skepticism of the science and motives behind the program, competing priorities for refuge staff, differing perceptions of regulatory and voluntary approaches, cost and availability of nonlead ammunition, and disregard by some about lead ammunition and human health risks. Staff identified numerous challenges implementing the program, many of which were external factors beyond the control of the participants. Understanding the factors affecting program implementation may help guide future efforts encouraging the voluntary use of nonlead ammunition., (Copyright © 2020 Elsevier Ltd. All rights reserved.)