Date of Award:
Master of Science (MS)
Department name when degree awarded
Fisheries and Wildlife
John A. Bissonette
The western mourning dove (Zenaida macroura) population has been declining since 1966. Data collected in 1951-52, in Fillmore, Utah, provided us a baseline for comparison with our study in the same area. Our approach was to determine whether a local population decline had occurred since the original data were collected, assess if trichomoniasis has impacted the local population, determine if changes in habitat structure affect foraging site selection, quantify changes in habitat, identify which habitats doves preferred, ascertain whether doves had responded to habitat change by changing food habits, and assess if changes in habitat were responsible in part for the local population decline. We found that population counts declined 72% and 82% from 1952 to 1992 and 1993, respectively. We determined that trichomoniasis was not an factor. in the decline. We observed that doves preferred foraging habitat characterized by a short and open structure and will not forage in the taller, denser vegetation that now dominates the study area. The most dramatic change in habitat was an 82% decline of land in winter wheat production. In 1951-52 and 1992-93, doves consumed wheat in greater frequency and volume than any other food item. Habitats selected for foraging were wheat fields following harvest, feedpens, hay storage yards, and weedy patches. Of these habitats, area in wheat fields and number of feedpens had changed extensively. The decline in wheat availability, either at harvested fields or feedpens, appears to have contributed to the local population decline. We used regression analysis to test the statewide relationship between the decline in the mourning dove population index, area in winter wheat production, and the number of farms with cattle and obtained significant results (R2 = .42, P = 0.001).
Ostrand, William D., "Disease and Habitat Change as Factors Associated with Mourning Dove Population Decline" (1995). All Graduate Theses and Dissertations. 6516.