North American Crane Working Group


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Spalding, M.G., and L.M. Stark. Eastern equine encephalitis in Florida whooping cranes. In: Hartup, Barry K., ed., Proceedings of the Eleventh North American Crane Workshop, Sep 23-27, 2008, Wisconsin Dells, Wisconsin (Baraboo, WI: North American Crane Working Group, 2010), p. 214.


Reproduced by permission of the North American Crane Working Group.


Two whooping cranes (Grus americana) that were part of separate projects to reintroduce whooping cranes in eastern North America died suddenly in Florida following a few days of abnormal behavior. The first case was a semi-captive bird on ultralight-led migration from Wisconsin to Florida in December 2004. The second case was a molting 10-year-old male and successful wild breeder that died in May, 2005. Clinical signs were lethargy, abnormal posture, isolation followed by attack by other birds, collapse, heart murmur, and death. Eastern equine encephalitis virus (alphavirus) was isolated from the liver of both birds. The most severe lesions were in the intestinal tract and liver. Evidence of exposure in sandhill cranes (G. canadensis) and other released whooping cranes indicate that summertime exposure is relatively frequent, may cause of summertime illness, but only occasionally causes death. These 2 deaths followed months of elevated seroconversion rates in Florida sentinels. Other factors, such as prior exposure, immune status, vaccination, molt or other pre-existing diseases may put individual birds at greater risk.