Camera Trap Study of the Mammal Communities Across an Urbanization Gradient

Urbanization impacts mammal communities due to habitat removal, resource abundance distribution, and the introduction of exotic species. Other studies have found that wildlife species richness is greatest at intermediate urbanization, while abundance is greatest in cities. This study was done to explore the mammal community across an urban to rural gradient in Pittsburg. Using motion-sensor camera traps, we documented small mammal pres­ence for 24 hours a day, finding patterns in mammal abundance, species richness, and community composition. Our hypothesis was that we will observe trends in mammal communities similar to other cities. Over six weeks, we placed two cameras in either a rural and semi-rural location, or an urban and semi-urban location, rotating their placement each week. We also recorded tracks and scat within the study location in a 15-minute survey. So far, we have collected data on six species over 42 trap nights. The urban environment had a much greater spe­cies abundance and richness than the rural locations. The urban mammal community was dominated by urban adaptor and exploiter species, such as the Virginia opossum (Didelphis virginiana) and house cat (Felis catus). There have been no mammal pictures captured at the rural, semi-rural, and semi-urban areas, possibly due to inclement weather. We are continuing to sample these locations. This study will help us determine the effects of urbanization on mammals and what steps we will need to take to improve urban biodiversity