HEMOGRAMS AND HEMATOZOA OF SHARP-SHINNED (ACCIPITER STRIATUS) AND COOPERS-HAWKS (ACCIPITER COOPERII) CAPTURED DURING SPRING MIGRATION IN NORTHERN NEW-YORK

Hemograms were determined for 26 Cooper's (Accipiter cooperii) and 55 sharp-shinned hawks (Accipiter striatus) captured during spring migrat ion (27 March to 12 May 1987) on the south shore of Lake Ontario, New York (USA), No significant differences were noted in packed cell volum e and estimated total solids between the species. However, Cooper's ha wks had significantly higher total white blood cell counts and higher concentrations of heterophils, monocytes, and eosinophils. Proportiona lly, lymphocytes made up a smaller percentage of the differential coun t in the Cooper's hawk. Eosinophil concentrations and percentages of t he differential count were significantly higher in the females of both species. Both species had a high prevalence of Leucocytozoon toddi an d Haemoproteus spp, infection. Haemoproteus nisi and H. elani were ide ntified in both hawks. Trypanosoma avium was identified in a single Co oper's hawk and Plasmodium circumflexum was identified in a sharp-shin ned hawk. Prevalence of Leucocytozoon toddi and Haemoproteus spp. infe ctions were significantly higher in the birds caught late in the sprin g as compared to those caught earlier in the spring; this was evidence for a spring recrudescence of patent parasite infections.