Helminths in ruffed grouse at the host's southeastern range boundary.

Carcasses of 268 ruffed grouse (Bonasa umbellus) collected in eastern Tennessee (USA) from October 1983 through February 1988 were examined between 16 January 1985 and 25 April 1988 for non-filarioid helminths. Three nematode species and one cestode species were found. The two most common parasites were the cecal worm Heterakis bonasae (81% prevalence, mean intensity +/- SD of 62 +/- 114) and the tapeworm Echinolepis carioca (27% prevalence, 30 +/- 73 mean intensity). Age and sex of host were sufficient to predict infection by both common species. Condition of host and year and month of collection also had significant effects on prevalence. Intensity of cecal worm infection varied with age and condition of host and with region and month of collection.