Get reliable science

On the western slope of the Sierra Madre Occidental of southeastern Sonora, Mexico, a 928 square kilometer conservation easement protects large stands of primary and secondary tropical deciduous forest (TDF).� Within this area, people sustain themselves through subsistence farming and low-density cattle ranching.� Though cattle may negatively impact tree diversity in areas where they roam, few researchers have quantified cattle foraging preferences for woody plant species, or tested hypotheses explaining potential impacts. �I investigated cattle foraging and ranging behavior in order to address the following questions: (1) are cows selecting (or avoiding) particular species of woody plant in the TDF?� And, (2) is woody plant diversity in their preferred foraging habitat different from woody plant diversity across all forested areas accessible to cows?� To quantify the woody plant component of cow diets, I designed and deployed animal-mounted time-lapse video and data logging equipment to record cow feeding and movement. �Using GPS data on cow foraging paths, I returned to documented feeding points and censused woody plants within a 5m by 5m area surrounding the eaten plant.� I also collected plant census data at 100m intervals across all habitat. �I then compared diversity in cow diet, preferred foraging areas, and all available habitat.� My results suggest that cows are not picky eaters� in terms of available species, they generally eat what is abundant, given the immediate choices in front of them. �Selective behavior, however, is more apparent at the habitat level, cows preferring to forage in areas that are more diverse compared to diversity across all available habitat.� A better understanding of cattle foraging and ranging behavior can help inform sustainable economic development practices and conservation, in Mexican TDF and in other multiple use forests.