The wild turkey is endemic to North America and has played a role in human cultures past and present. However, with the turkey's elusive behavior some aspects of its ecology are challenging to understand. Diet is one of these difficult aspects to study. The purpose of this study was to determine the diet selection of wild turkeys in central Utah using non invasive stable isotope technology. We hypothesize that turkey diet is highly specific, that consumption of specific plant species correlates with the needs of the individual turkey, and that stable isotope analysis will reveal patterns in annual dietary intake. Vegetative forage, turkey feces, and feather samples were collected from the Salt Creek area east of Mt. Nebo during 2007 and 2008. Feces samples were identified to bird sex and forage samples were identified to family or growth form (grass, forb, and shrub) when species could not be determined. Carbon isotope analysis of turkey feces and dietary forage using a mass spectrometer revealed that composition of turkey diet changed seasonally and yearly. Isotope analysis of dietary forage according to vegetative growth form revealed that turkey diet for the spring of 2007 contained approximately 46.0% grasses, 30.0% forbs, and 24.0% shrubs and trees. The summer diet for 2007 consisted of 39.0% grasses, 31.0% forbs, and 30.0% shrubs and trees. During spring 2008, grasses comprised 10.3% of the diet whereas forbs and tree/shrubs constituted 53.0% and 36.7%, respectively. Turkey summer diet for 2008 was found to consist of 13.1% grasses, 48.5% forbs, and 38.4% shrubs/trees. Isotope analysis of turkey feathers revealed no significant patterns in isotope signatures in relation to vegetation type and season of year. Stable isotope signatures resulting from fecal analysis reflect opportunistic foraging behavior as birds utilized a wide variety of forages throughout the year. Our findings suggest habitat structure and type play a more major role in wild turkey survival then food type. These findings also strengthen the need to rigorously evaluate turkey habitat prior to reintroduction with respect to vegetative composition and structure and their relationship with wild turkey behavior and life processes.
College and Department
Life Sciences; Plant and Wildlife Sciences
BYU ScholarsArchive Citation
Stearns, Benjamin D., "Diet Reconstruction of Wild Rio-Grande Turkey of Central Utah Using Stable Isotope Analysis" (2010). Theses and Dissertations. 2102.
diet, Rio Grande, stable isotopes, Utah, wild turkey