Date of Award
M.S. in Biological Science
Jason D. Hoeksema
Christopher J. Leary
Habitat loss and habitat degradation are major drivers of the current biodiversity crisis. Nowhere else are these threats more severe than in the tropics. Because the tropics are estimated to contain as much as 60% of all the species on Earth, they are critically important for the conservation of biodiversity. To conserve species we need to understand both the factors that lead to extinction and how the taxa that persist are able to adapt to the rapid anthropogenic change of their environment. The Ocellated Turkey (Meleagris ocellata) is a Neotropical galliform bird of conservation concern because it faces a rapidly changing environment. The goal of this thesis is two fold: 1) to expand our understanding of the natural history of the Ocellated Turkey (Meleagris ocellata), and 2) to document the behavioral responses of this species to different levels of anthropogenic habitat modification. Chapter One describes a radiotelemetry study of adult males. This investigation is the first published record of the home range use and movement patterns of adult males of this species during the breeding season. These birds shohome ranges that were highly variable in size and composition (MCP x ?x= 969 ± 922 ha, 95%FK x ?x= 692 ± 819 ha, 50%FK x ?x= 90 ± 138 ha). In comparison to other similarly sized Galliformes, the Ocellated Turkey home range is quite large. The average movement rate also varied greatly between individuals (x ?x= 437 ± 264 m/h). A few individuals restricted their movements to intact forest only, while others spent all day in open pasture. The majority of radiotagged males (7 of 12) spent 50% or more of their time in areas without closed canopy cover. Chapter Two describes the association of habitat disturbance with male movement patterns and select indicators of health. There were no significant differences in home range size, blood and fecal parasites, feather barring regularity, male fleshy ornaments, and H:L ratios among the disturbance types. Additionally, most of the feather reflectance data did not significantly differ between disturbance levels (low, intermediate, and high), but I did find differences in the blue ocelli of the secondary tail coverts among disturbance levels. The dominant ultraviolet spectrum hue of the ocelli were negatively correlated with coccidian parasite load but the dominant red spectrum hue was positively correlated with this parasite. Chapter Three presents various results from the field study that further our knowledge of the natural history of this species, including an analysis of flocking behavior, fecal parasite distribution at the landscape level, and notes on predator inspection behavior, the submission display of non-breeding males and their early attempts at courtship. Flocks were larger and sholess vigilance in open habitat but did not have a different foraging there compared to flocks in the forest. Mapping of the number of parasites found in feces identified “hot spots” with high concentrations of parasites, which surprisingly included a shade coffee grove. Young males used the double wing turn behavior to deflect aggression from alpha males. Incomplete action patterns for gobbling and strutting were observed in young male flocks. The results of this study suggest that a matrix of rainforest and cattle pasture is not harmful to Oocellated Tturkey health, although further studies that include measures of survivorship and fecundity are needed to model accurately this species’ population viability in an anthropogenic environment.
Martin, Thomas Hughes, "Responses of the Ocellated Turkey (Meleagris ocellata) to Human Disturbance" (2017). Electronic Theses and Dissertations. 1279.