West Nile virus is a deadly virus for young cranes. In testing two different vaccines on both adult sandhill cranes (Grus canadensis), we discovered that some blood parameters are altered by exposure to the virus. White blood cell counts were the most obvious, and may be used as an indicator of West Nile virus exposure in cranes. Other hematology and serum chemistry results were studied and only hematocrit, percent heterophils, and percent lymphocytes were of interest, along with the already published information on titers encountered in experimental infections. Clinical pathology results showed challenged cranes, whether vaccinated or not, had a decrease in their hematocrits and an elevation of 2.5-fold in their white blood cell counts as compared to unchallenged control sandhill cranes. No differences were apparent in the differential counts of heterophils and lymphocytes. Our work would suggest that a combination of white blood cell counts and antibody titers can be used to diagnose and assess the severity of West Nile virus infections in cranes.