Abstract

In December 2013, it became evident that an irruption (Latin irruptus, past participle of irrumpere, from in- + rumpere to break) "a sudden upsurge in numbers especially when natural ecological balances and checks are disturbed" was occurring in snowy owls (Bubo scandiacus) in the northeastern U.S. This investigation began as an emergency call for veterinarians and biologists to collaborate and expand our knowledge of these amazing creatures. Long known as the "Harry Potter Owl," they are one of the largest owls in North America with a wing span of up to five feet.

Project SNOWStorm is the collective effort of biologists and veterinarians to better understand and track the population movements and health of snowy owls during this event. No funds were set aside for this since it was unexpected; therefore, a "crowd-funding" website was developed by the Ned Smith Center for Nature and Art, Millersburg, PA, and Project SNOWstorm was initiated. Twenty-two GPS/GSM transmitters were purchased and deployed on owls captured in various NE U.S. states. When possible, blood was drawn to establish normal blood chemistry and CBC parameters. Owl carcasses were also examined; each state conducted and funded their own health assessments and data were shared. For those unable to fund necropsy and test costs, additional funds from Project SNOWStorm were set aside to complete pathology and tissue analyses.

This paper presents a portion of the work done by Project SNOWstorm team members during the Snowy Owl irruption in the winter of 2013–2014. The authors conducted gross necropsies and morphometrics on birds collected from seven states (New Jersey, Maryland, Pennsylvania, New York, Massachusetts, Wisconsin, and Maine) between December 2013 and August 2014. Specific post-mortem diagnostics included radiographs, histopathology, microbiology, parasitology, and toxicology screens for heavy metals and anti-coagulant rodenticides. Authors also collected information on injured birds presenting to wildlife rehabilitators in these states during this time period. Summaries to be presented include a compilation of the general causes of morbidity and mortality, body condition of the presenting animals, gross post-mortem and histopathology findings, and exposure levels to contaminants. As of the submission of this abstract, 60 snowy owl necropsies have been conducted by partners, with many more live-sampled, and/or banded/released.

Acknowledgements

Authors thank members and staff of Project SNOWstorm, Project OwlNet, Tri-State Bird Rescue and Research, the Maryland Zoo, the Ned Smith Center for Nature and Art, USDA Wildlife Services, Avian Haven Wild Bird Rehabilitation Center, wildlife rehabilitators, and the University of Pennsylvania for administrative support and funding of all veterinary pathology efforts.

* Presenting author

Literature Cited

1.  Potapov E, Sale R. The Snowy Owl. London: T&AD Poyser/Bloomsbery Publishing Plc.; 2012.

2.  www.projectSNOWstorm.org

3.  www.ebird.org