Blood parasites in sage-grouse from Nevada and Oregon.

TitleBlood parasites in sage-grouse from Nevada and Oregon.
Publication TypeJournal Article
Year of Publication2003
AuthorsDunbar MR, Tornquist SJ, Giordano MR
JournalJournal of wildlife diseases
Date Published2003 Jan
KeywordsAnimals, Bird Diseases, Birds, Female, Haemosporida, Hematocrit, Nevada, Oregon, Parasitemia, Plasmodium, Prevalence, Protozoan Infections, Animal, Reproduction, Seasons

Peripheral blood smears from 196 adult and yearling female greater sage-grouse (Centrocercus urophasianus) were examined for blood parasites (167 from the breeding and 29 from the brood-rearing season) to determine prevalence of blood parasites, to attempt to correlate infection with chick survival, and to establish base-line values of prevalence in sage-grouse from Nevada and Oregon (USA). Birds were captured and released on two study areas during 1999-2001; Sheldon National Wildlife Refuge (SNWR) in northwestern Nevada, and Hart Mountain National Antelope Refuge (HMNAR) in southeastern Oregon. Birds from a third study area, Beaty's Butte grazing allotment (BB) in southeastern Oregon, were sampled in 2000 and 2001. Overall, 19 birds (10%) were positive for Leucocytozoon lovati (= L. bonasae), 1 (0.5%) for Plasmodium pedioecetii, and 2 (1%) for microfilariae. Although prevalence of L. lovati on HMNAR was 39% during the breeding season in 1999 and 100% during the brood-rearing season in 2000, statistically, prevalence of L. lovati among study areas and years was not different. However, there were statistical differences between capture periods. Overall, 31% of the hens were positive for L. lovati during the brood-rearing season compared to 6% during the breeding season. There was no difference in packed cell volume between infected and non-infected birds and no difference between age-classes. However, mean sage-grouse productivity on HMNAR was higher (1.6 chicks/hen) for non-infected (n = 10) compared to infected hens (0.7 chicks/hen; n = 7), during 1999. Based on these limited observations on HMNAR in 1999, the possible effects that L. lovati may have on young sage-grouse could be detrimental to sage-grouse populations in Nevada and Oregon.

Alternate JournalJ. Wildl. Dis.