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T. Hollmen

Publications and source records attributed to T. Hollmen.

8 recordsLinked to original sources
USGS2007

Polycyclic aromatic hydrocarbon exposure in Steller's eiders ( Polysticta stelleri ) and harlequin ducks ( Histronicus histronicus ) in the Eastern Aleutian Islands, Alaska, USA

Seaducks may be affected by harmful levels of polycyclic aromatic hydrocarbons (PAHs) at seaports near the Arctic. As an indicator of exposure to PAHs, we measured hepatic enzyme 7-ethoxyresorufin- O -deethylase activity (EROD) to determine cytochrome P4501A induction in Steller's eiders ( Polysticta stelleri ) and Harlequin ducks ( Histronicus histronicus ) from Unalaska, Popof, and Unga Islands (AK, USA) in 2002 and 2003. We measured PAHs and organic contaminants in seaduck prey samples and polychlorinated biphenyl congeners in seaduck blood plasma to determine any relationship to EROD. Using Akaike's information criterion, species and site differences best explained EROD patterns: Activity was higher in Harlequin ducks than in Steller's eiders and higher at industrial than at nonindustrial sites. Site-specific concentrations of PAHs in blue mussels ([ Mytilus trossilus ] seaduck prey; PAH concentrations higher at Dutch Harbor, Unalaska, than at other sites) also was important in defining EROD patterns. Organochlorine compounds rarely were detected in prey samples. No relationship was found between polychlorinated biphenyl congeners in avian blood and EROD, which further supported inferences derived from Akaike's information criterion. Congeners were highest in seaducks from a nonindustrial or reference site, contrary to PAH patterns. To assist in interpreting the field study, 15 captive Steller's eiders were dosed with a PAH known to induce cytochrome P4501A. Dosed, captive Steller's eiders had definitive induction, but results indicated that wild Steller's eiders were exposed to PAHs or other inducing compounds at levels greater than those used in laboratory studies. Concentrations of PAHs in blue mussels at or near Dutch Harbor (∼1,180–5,980 ng/g) approached those found at highly contaminated sites (∼4,100–7,500 ng/g).

Environmental Toxicology and Chemistry↗
USGS2005

Effects of dietary selenium exposure in captive American common eiders

We conducted two studies of Se exposure in captive common eiders (Somateria mollissima). In Study 1, eiders were fed diets with added Se (as L-selenomethionine) in concentrations increasing from 10 ppm to 80 ppm. In Study 2, eiders received control, low exposure (20 ppm Se), and high exposure (60 ppm Se) diets. One duck in the high exposure group in Study 2 died after 36 days. Remaining high exposure ducks in Study 2 and ducks in Study 1 were euthanized after losing 25-30% of their body weight, which occurred after 41 days and 60-78 days, respectively. Body weights did not differ between control and low exposure ducks in Study 2. At the end of Study 1, the mean Se concentration in blood was 32 ppm wet weight (ww). In Study 2, mean blood Se reached 14 ppm ww in the low exposure group and 17 ppm ww in high exposure ducks. Mean Se concentrations in liver were 1252 ppm dry weight (dw) in Study 1, and 351 and 735 ppm dw, respectively, in the low and high exposure groups of Study 2. Oxidative stress was evidenced by Se-associated effects on glutathione metabolism, but not entirely in the same manner as with previous laboratory studies in mallards. In plasma, activities of total and Se-dependent glutathione peroxidase increased with time. As Se concentrations in liver increased, Se-dependent glutathione peroxidase, glutathione reductase, oxidized glutathione, and the ratio of hepatic oxidized to reduced glutathione increased. Total and protein bound sulfhydryl concentrations, reduced glutathione, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase in liver were negatively correlated with Se concentrations in the liver. In Study 2, spleen weights were significantly lower in ducks receiving 60 ppm Se than in those receiving 20 ppm. Gross lesions associated with high Se exposure included emaciation, absence of thymus, loss of nails from digits, and alopecia. Microscopic lesions included severe depletion of lymphoid organs, hepatopathy, and necrosis of feather pulp and feather epithelium. Common eiders fed high levels of Se lost weight and developed lesions similar to findings in experimental mallards, but they accumulated greater Se concentrations in tissues, particularly liver. Field studies have shown that apparently healthy seaducks generally have higher levels of Se in liver than healthy fresh water birds, but lower than the concentrations we found in our study. We conclude common eiders and probably other seaducks have a higher threshold, or adverse effect level, of Se in tissues than fresh water species.

Conference Paper↗
USGS2004

Intestinal helminths in mourning doves (Zenaida macroura) from Arizona, Pennsylvania, South Carolina, and Tennessee, U.S.A.

We examined 115 hunter-killed mourning doves ( Zenaida macroura ) from 4 states (Arizona, Pennsylvania, South Carolina, and Tennessee, U.S.A.) in 1998 and 1999 to investigate geographical variation in the prevalence and intensity of intestinal helminth infections. Four intestinal helminth species were identified: Killigrewia delafondi , Ornithostrongylus crami , Ascaridia columbae , and Capillaria obsignata . The number of worms (all helminth species combined) per infected bird ranged from 1 to 166 (mean ± SE = 12.7 ± 7.45, median = 2.0). Filarids, Aproctella stoddardi , were found in 2 birds but were probably adhering to the outside of the intestine. Overall, 18% of the doves were infected with 1 or more species of helminths. The percentage of doves infected with at least 1 helminth species varied from 4% in Arizona to 27% in South Carolina. Mixed infections occurred in only 3 individuals (14% of infected birds). We found no significant differences in prevalence of infection among any of the 4 helminths by host age or sex, and prevalences were too low to test for differences among states. The intensity of O. crami was higher in males than in females but did not differ significantly among states. Intensities of the other 3 helminths did not differ by sex or state, and we found no differences in helminth intensity by age. Intestinal length was significantly greater in infected than in uninfected birds.

Arizona, Pennsylvania, South Carolina, Tennessee↗
USGS2002

Isolation and characterization of a reovirus from common eiders (Somateria mollissima) from Finland

Samples of brain, intestine, liver, lung, spleen, and bursa of Fabricius were collected from five common eider ( Somateria mollissima ) duckling carcasses during a die-off in the western Gulf of Finland (59°50′N, 23°15′E) in June 1996. No viral activity was observed in specific-pathogen-free chicken embryos inoculated with tissue suspensions, but samples of bursa of Fabricius from three birds were positive when inoculated into Muscovy duck ( Cairina moschata ) embryo fibroblasts. The isolates were characterized as nonenveloped RNA viruses and possessed several characteristics of the genus Orthoreovirus . Virus particles were icosahedral with a mean diameter of 72 nm and were stable at pH 3.0; their genome was separated into 10 segments by polyacrylamide gel electrophoresis. Mallard ( Anas platyrhynchos ) ducklings experimentally infected with the eider reovirus showed elevated serum activities of aspartate aminotransferase, creatine kinase, and lactate dehydrogenase enzymes and focal hemorrhages in the liver, spleen, and bursa of Fabricius. During 1997–99, the prevalence of neutralizing antibodies to the isolated virus ranged from 0 to 86% in 302 serum samples collected from incubating eider hens at three nesting areas along coastal Finland. The highest seroprevalence was found in Hanko in 1999, just weeks before reports of an uninvestigated mortality event resulting in the death of an estimated 98% of ducklings at that location. These findings raise the question of potential involvement of the virus in poor duckling survival and eider population declines observed in several breeding areas along coastal Finland since the mid-1980s.

Gulf of Finland↗
USGS2001

Use of serum biochemistry to evaluate nutritional status and health of incubating common eiders (Somateria mollissima) in Finland

During 1997–1999, we collected serum samples from 156 common eider ( Somateria mollissima ) females incubating eggs in the Finnish archipelago of the Baltic Sea. We used serum chemistry profiles to evaluate metabolic changes in eiders during incubation and to compare the health and nutritional status of birds nesting at a breeding area where the eider population has declined by over 50% during the past decade, with birds nesting at two areas with stable populations. Several changes in serum chemistries were observed during incubation, including (1) decreases in serum glucose, total protein, albumin, β‐globulin, and γ‐globulin concentrations and (2) increases in serum uric acid, creatine kinase, and β‐hydroxybutyrate concentrations. However, these changes were not consistent throughout the 3‐yr period, suggesting differences among years in the rate of carbohydrate, lipid, and protein utilization during incubation. The mean serum concentrations of free fatty acids, glycerol, and albumin were lowest and the serum α‐ and γ‐globulin levels were highest in the area where the eider population has declined, suggesting a role for nutrition and diseases in the population dynamics of Baltic eiders.

Physiological and Biochemical Zoology↗
USGS2000

Infectious bursal disease virus antibodies in eider ducks and Herring Gulls

We measured antibodies to infectious bursal disease virus (IBDV) in blood of nesting Common Eider ( Somateria mollissima ) females and immature Herring Gulls ( Larus argentatus ) in the Baltic Sea, and in blood of Spectacled Eider ( Somateria fischeri ) females nesting in a remote area of western Alaska. Positive (≥ 1:16) IBDV titers occurred in 75% of the eiders and 45% of the Herring Gull chicks. In eiders, the prevalence of positive titers differed among locations. We found no evidence that IBDV exposure impaired the immune function of Herring Gull chicks, based on their response to inoculation of sheep red blood cells. We suggest that eider ducks and Herring Gulls have been exposed to IBDV, even in locations where contact with poultry is unlikely. The presence of this virus in wild bird populations is of concern because it causes mortality of up to 30% in susceptible poultry.

Alaska↗
USGS2000

Metals and trace elements in tissues of common eiders (Somateria mollissima) from the Finnish archipelago

We sampled Common Eiders ( Somateria mollissima ) at five locations near coastal Finland in 1997 and 1998 for evidence of exposure to arsenic, cadmium, chromium, copper, iron, mercury, magnesium, molybdenum, lead, selenium, and zinc. Livers and kidneys were collected from adult males and females found dead and hunter-killed males, and livers were collected from ducklings. Two adult females, one of which had an ingested lead shot in its gizzard, were poisoned by lead. The concentration of metals and trace elements that we found in tissues of eiders, other than the two lead poisoned birds, were not high enough to have independently caused mortality.

Ornis Fennica↗