Intravenous lipid emulsion (ILE) therapy has shown promise as a treatment option for a variety of lipophilic toxins. Two birds presented for suspected ingestion of a toxic substance. A blue-and-gold macaw (Ara ararauna) presented after chewing a block of bromethalin rodenticide without overt clinical signs at the time of presentation. Additionally, a free-ranging bald eagle (Haliaeetus leucocephalus) was found weak and depressed near a municipal landfill after presumptive ingestion of pentobarbital. Both birds were treated with ILE therapy for potential intoxication without any adverse events. The macaw was clinically normal after 3 days of hospitalization and at a 1-week reevaluation. The eagle was transferred to a rehabilitation center after markedly improved mentation and strength and was released 7 days later. Clinicians should consider ILE therapy for the treatment of lipophilic toxicities; however, monitoring is recommended for persistent lipemia and other adverse effects that have been reported in the veterinary literature.

The objective of this study was to evaluate the pharmacokinetic properties of ceftiofur crystalline free acid (CCFA) administered intramuscularly at dosages of 10 and 20 mg/kg in bald eagles (BAEAs) (Haliaeetus leucocephalus). Ceftiofur crystalline free acid is a long-acting, injectable, third-generation cephalosporin antibiotic drug. A prospective, randomized, complete crossover design was used for this pharmacokinetic investigation. CCFA (10 or 20 mg/kg) was administered intramuscularly, and blood samples were obtained from 6 adult, nonreleasable, healthy BAEAs at predetermined sampling times. After a 4-week washout period, the protocol was repeated with each bird receiving the dose not given during the initial sample collection according to the randomized crossover design. Plasma ceftiofur free acid equivalents were quantified and data were analyzed by a noncompartmental pharmacokinetic approach. The mean observed peak plasma concentrations were 9.23 µg/mL and 15.08 µg/mL for 10 and 20 mg/kg CCFA IM administration, respectively. The mean observed time to maximum plasma concentration was 18 and 17.6 hours, and the mean terminal elimination half-life was 32.38 and 38.08 hours for intramuscular administration of 10 and 20 mg/kg CCFA, respectively, in the BAEAs. Reported minimum inhibitory concentrations of raptor bacterial isolates from a prior study was used to determine the target minimum inhibitory concentration of 1 µg/mL selected for this investigation. From the previously published information, a target plasma concentration of 4 µg/mL was determined for the CCFA in the BAEAs. From the results of this study, CCFA may be dosed every 60 and 110 hours at 10 mg/kg IM, and every 80 and 160 hours at 20 mg/kg IM in BAEAs.

We analyzed concentrations and trends of perfluoroalkyl substances (PFAS) in blood plasma samples of bald eagle (Haliaeetus leucocephalus) nestlings at 6 study areas in the upper Midwest of the United States, 2006 to 2015, and long-term trends at 2 Lake Superior (USA/Canada) sites, 1995 to 2015. Nestling blood plasma concentrations of the sum of 15 PFAS analytes (∑PFAS) differed among study areas and were highest at the 3 industrialized river sites: pools 3 and 4 of the Mississippi River (pools 3 + 4; geometric mean [GM] = 754 μg/L; range = 633-2930), the Mississippi National River and Recreation Area (GM = 687 μg/L; range = 24-7371), and the lower St. Croix National Scenic Riverway (GM = 546 μg/L; range = 20-2400). Temporal trends in ∑PFAS in nestling plasma differed among study areas; concentrations decreased at pools 3 + 4, Mississippi National River and Recreation Area, and lower St. Croix National Scenic Riverway, but not at the most remote sites, the upper St. Croix River and Lake Superior. Overall, perfluorooctanesulfonate (PFOS) was the most abundant analyte at all study areas, and perfluorodecanesulfonate (PFDS) the second most abundant at industrialized river sites although not at Lake Superior; concentrations of both these analytes declined from 2006 to 2015 over the study area. In addition, nestling age significantly influenced plasma concentrations of ∑PFAS and 7 of the 12 analytes. For these analytes, concentrations increased by 1 to 2%/d as nestlings grew, indicating that age should be considered when using nestling plasma to assess PFAS. Environ Toxicol Chem 2021;40:754-766. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Freshwater fish in several regions of New York State (NYS) are known to contain concentrations of mercury (Hg) associated with negative health effects in wildlife and humans. We collected blood and breast feathers from bald eagle (Haliaeetus leucocephalus) nestlings throughout NYS, with an emphasis on the Catskill region to determine their exposure to Hg. We assessed whether habitat type (lake or river), region (Delaware-Catskill region vs. rest of NY) or sample site elevation influenced Hg concentrations in bald eagle breast feathers using ANCOVA. The model was significant and accounted for 41% of the variability in log10 breast feather Hg concentrations. Mercury concentrations in nestling breast feathers were significantly greater in the Delaware-Catskill Region (geometric mean: 14.5 µg/g dw) than in the rest of NY (7.4 µg/g, dw), and greater at nests located at higher elevations. Habitat type (river vs. lake) did not have a significant influence on breast feather Hg concentrations. Geometric mean blood Hg concentrations were significantly greater in Catskill nestlings (0.78 µg/g ww) than in those from the rest of NY (0.32 µg/g). Mercury concentrations in nestling breast feathers and especially blood samples from the Delaware-Catskill region were generally greater than those reported for most populations sampled elsewhere, including areas associated with significant Hg pollution problems. Bald eagles can serve as valuable Hg bioindicators in aquatic ecosystems of NYS, particularly given their broad statewide distribution and their tendency to nest across all major watersheds and different habitat types.

A subadult, male bald eagle (Haliaeetus leucocephalus) was evaluated after being found unable to fly, with large eschars on the dorsal head and right stifle. Because of the appearance and location, the lesions were believed to be caused by an electrical injury. Treatment included oral antibiotics, nonsteroidal anti-inflammatory drugs, pain medication, surgical debridement of the eschars, and trephining of the affected inner table of the cranium. A full-thickness skin graft was performed to expedite wound healing and minimize holding time. After 6 weeks, the bird had new feather growth on its dorsal head and was released. This is the first report, to our knowledge, of a nonmesh, full-thickness skin graft in an avian species. Full-thickness skin grafts should be considered as a surgical option in juvenile or adult avian patients with large dorsal head wounds.

Mercury (Hg) exposure was evaluated in bald eagles (Haliaeetus leucocephalus) in the lower Penobscot River watershed (PRW) in Maine to assess whether Hg discharges from a chlor-alkali plant (HoltraChem) influenced Hg concentrations in nestling tissues. Mean Hg concentrations in nestling blood and breast feathers sampled in marine and estuarine areas potentially contaminated with Hg from HoltraChem (the potential Hg impact zone) were significantly greater than those from reference sites spanning the Maine coast. To place Hg exposure in the potential Hg impact zone into a broader context, Hg exposure in bald eagle nestlings from four habitat types in the PRW was assessed. Mercury concentrations varied significantly across habitat types within the PRW, generally following the pattern: marine=estuarine

A 30-year-old bald eagle ( Haliaeetus leucocephalus) was presented with a history of hyporexia and lethargy. Results of initial hematologic testing, biochemical analysis, and fecal examination were unremarkable, and clinical signs did not resolve with supportive care and management changes. Results of echocardiography, based on auscultation of a murmur, and coelomic endoscopy, based on the presence of a soft tissue opacity on radiographs, as well as an aspergillosis panel were largely unsuccessful in determining a definitive diagnosis. Euthanasia was performed after the eagle did not recover from anesthesia after endoscopy. Necropsy results demonstrated bilateral testicular seminomas with metastases to the ventriculus. This case demonstrates an abnormal metastasis of a common reproductive tumor in an avian species.

Management or conservation targets based on demographic rates should be evaluated within the context of expected population dynamics of the species of interest. Wild populations can experience stable, cyclical, or complex dynamics, therefore undisturbed populations can provide background needed to evaluate programmatic success. Many raptor species have recovered from large declines caused by environmental contaminants, making them strong candidates for ongoing efforts to understand population dynamics and ecosystem processes in response to human-caused stressors. Dynamic multistate occupancy models are a useful tool for analyzing species dynamics because they leverage the autocorrelation inherent in long-term monitoring datasets to obtain useful information about the dynamic properties of population or reproductive states. We analyzed a 23-year bald eagle monitoring dataset in a dynamic multistate occupancy modeling framework to assess long-term nest occupancy and reproduction in Lake Clark National Park and Preserve, Alaska. We also used a hierarchical generalized linear model to understand changes in nest productivity in relation to environmental factors. Nests were most likely to remain in the same nesting state between years. Most notably, successful nests were likely to remain in use (either occupied or successful) and had a very low probability of transitioning to an unoccupied state in the following year. There was no apparent trend in the proportion of nests used by eagles through time, and the probability that nests transitioned into or out of the successful state was not influenced by temperature or salmon availability. Productivity was constant over the course of the study, although warm April minimum temperatures were associated with increased chick production. Overall our results demonstrate the expected nesting dynamics of a healthy bald eagle population that is largely free of human disturbance and can be used as a baseline for the expected dynamics for recovering bald eagle populations in the contiguous 48 states.

A male juvenile bald eagle ( Haliaeetus leucocephalus) was admitted to the Wildlife Center of Virginia with a left humeral fracture a large quantity of anthropogenic debris in the ventriculus, a blood lead level of 0.616 ppm, and clinical signs consistent with chronic lead toxicosis. Because of the poor prognosis for recovery and release, the eagle was euthanatized. Lead isotope analysis was performed to identify potential anthropogenic sources of lead in this bird. The lead isotope ratios in the eagle\'s femur (0.8773), liver (0.8761), and kidneys (0.8686) were most closely related to lead paint (0.8925), leaded gasoline (0.8450), and zinc smelting (0.8240). The lead isotope ratios were dissimilar to lead ammunition (0.8179) and the anthropogenic debris in the ventriculus. This case report documents foreign body ingestion in a free-ranging bald eagle and demonstrates the clinical utility of lead isotope analysis to potentially identify or exclude anthropogenic sources of lead poisoning in wildlife patients.

An adult bald eagle ( Haliaeetus leucocephalus) presented for nystagmus and an inability to fly. On physical examination, the eagle was open-mouth breathing and tachycardic at 200 beats per minute, had a wrinkled cere and sunken eyes, and was an estimated 10% dehydrated. Additionally, the eagle was extremely weak, with neurologic abnormalities including bilateral proprioceptive deficits, nystagmus, and no pupillary light reflex in the left eye. Despite aggressive treatment, the eagle continued to decline rapidly and subsequently died. On histologic examination, diffuse and widespread infiltration of neoplastic lymphocytes was present in the brain, optic nerves, and pecten. Immunohistochemical PAX-5 labeling confirmed B-cell lymphoma confined to the eye and nervous system. Test results for select avian retroviruses, Marek\'s disease, West Nile virus, avian influenza viruses, and Mycoplasma were negative. To our knowledge, this is the first report of B-cell lymphoma in a bald eagle. Although rare, this condition is a differential diagnosis in cases of neurologic or ocular diseases in birds.