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Amy W. O'Donnell

Publications and source records attributed to Amy W. O'Donnell.

2 recordsLinked to original sources

Highly pathogenic avian influenza virus H5N1 in double-crested cormorants (Nannopterum auritum) of the Chesapeake Bay, USA

Double-crested Cormorants ( Nannopterum auritum ) have historically exhibited low levels of infection and antibodies to avian influenza virus (AIV). The recent global expansion of clade 2.3.4.4b A/goose/Guangdong/1/1996 highly pathogenic (HP) avian influenza virus H5N1 (HPAI H5N1) has resulted in large-scale mortalities across diverse waterbird taxa including cormorants. We sampled 32 and 29 Double-crested Cormorants breeding in the Chesapeake Bay, US, during the summers of 2023 and 2024, respectively, to assess HPAI H5N1 infection and AIV antibodies. Although no mortality was observed in the area, one bird sampled in 2023 was infected with HPAI H5N1. Additionally, 21/31 individuals in 2023 and 10/25 individuals in 2024 for which sera were collected had AIV antibodies. Based on additional testing using hemagglutination inhibition, virus neutralization, and an enzyme-linked lectin assay, 94 and 100% (2023 and 2024, respectively) of the seropositive birds tested positive for antibodies to both H5 and N1, suggesting previous infection with HPAI H5N1. These results are consistent with survival and limited clinical effects related to HPAI H5N1 infections. Furthermore, these results suggest that population immunity to HPAI H5N1 within the Chesapeake Bay might reduce future infections and potential population impacts should HP H5N1 remain on the landscape, though immunity may be waning across time. Because results are based on a single population, additional testing for both infection and antibodies as well as continued monitoring could enhance understanding of antibody persistence.

Maryland, Virginia

Dust management at an active construction area impacts monarch distribution

The North American population of monarch butterflies ( Danaus plexippus) is experiencing dramatic declines, necessitating investigations into challenges facing this species that can be resolved through management actions. For instance, dust made airborne by heavy equipment driving along a dirt road can settle on roadside vegetation, resulting in reduced use by monarchs. Dust accumulation on areas where floral nectaries such as leaves, stems, and flowers may be present could reduce the ability of pollinators, such as monarchs, to access nectar from flowering plants needed during migration. One such challenge was observed on Poplar Island, an island restoration project located in the Maryland portion of the Chesapeake Bay, USA. To determine if road watering would result in notable reductions of dust accumulation on adjacent roadside vegetation, and if such a reduction in dust would affect monarch use of treated habitat, water was applied via spraying to sections of the roadway during the 2022 fall migration period. Treatment areas where water was applied to the road were found to have significant reductions in dust accumulation ( P ≤0.001) as well as significantly higher use by monarchs ( P = 0.002), relative to non-watered control areas. While these results indicate potential utility of road watering to support monarchs at sites with high dust accumulation, numerous additional elements such as water usage and logistical constraints must also be considered. While limited in scope, these data do provide a notable proof-of-concept for managing this issue at other sites and can be built upon with further research.

Maryland