| This thesis investigates the relationship between individual behavior and the spatial structure of carnivore populations, using two different modeling approaches. The first, uses individual-level fitness considerations to predict how social structure varies in relation to resource characteristics, foraging behavior and population density. The second, explored in greater detail, uses a spatially-explicit home range model for carnivores based on movement and responses to conspecific scent marks. Analysis shows that a model for carnivore home ranges, proposed by Lewis and Murray (1993), reflects the macroscopic pattern of home ranges obtained by scaling two simple empirically-founded rules describing the movement and scent-marking behavior of individuals. The derivation establishes a mechanistic connection between the parameters of the Lewis and Murray (1993) model and and underlying description of individual behavior. I show that solution of the model equations in two dimensions yields home ranges and scent mark distributions consistent with those observed in empirical studies of carnivores. The results suggest that much of the variations in home range and scent-marking patterns observed in different carnivore populations can be explained by simple differences in individual movement and scent marking behavior. The model is then used to characterize coyote (Canis latrans) home ranges in the Hanford Arid Lands Ecological Reserve, Washington and the Blacktail Plateau region of Yellowstone National Park, Wyoming. To my knowledge, this is the first time a mechanistic, rather than a statistical, model has been used to characterize animal home ranges. The results of the model fitting shows that the spatially-explicit carnivore home range model accurately captures the variation in home range shape and the degree of exclusivity in space-use along different home range boundaries. I show further that since the model is mechanistic, the model fits can be used to obtain predictions for individual movement and scent marking behavior, illustrating that the development and application of mechanistic home range models offers a promising way to integrate theoretical and empirical studies of carnivore home ranges. |
