Biochemical and trace element analyses of blood from wild Whooping Cranes ( Grus americana) were performed to assess the health of the only self-sustaining, migratory population in North America. Juvenile cranes ( n=31) approximately 49-70 d-old were sampled at Wood Buffalo National Park, Northwest Territories, Canada, in midsummer from 2010 to 2012. Archived serum ( n=24) and whole blood ( n=31) samples from captive juvenile cranes were selected as age-matched controls. Reference values were calculated for serum biochemical analytes and trace elements in whole blood from the captive juvenile Whooping Cranes reared under controlled conditions and with known health histories. Several statistical differences among blood biochemical and trace element values of the wild and captive juveniles were identified and were likely attributable to dietary differences between the populations.