A comparison of arthropod abundance and arthropod mediated predation services in urban green spaces

The need to conserve biodiversity and ecosystem services in urban landscapes is widely recognised, yet specific planning and design strategies that promote conservation in urban areas are limited. Little is known about the ability of different types of urban green spaces to support biodiversity and provide ecosystem services. In this study, we compared the abundance of beneficial arthropods (predators and bees) and measured predation services in two different types of green space, areas of turf and prairies. Beneficial arthropods and predation services were measured three times during the 2011 field season in six Chicago (IL, USA) parks that contained both turf and prairie. Using a repeated measures analysis, we found bee abundance was significantly higher in the prairie compared to turf by August, and predator abundance was higher in the prairie throughout the summer. While predation services were not significantly different between the turf and prairie in June, predation steadily increased in the prairie over the course of the summer with significantly higher rates of predation by August. Of the predators measured, spiders were positively correlated with prairie habitat and negatively correlated with the survival of pest insects. We found turf and prairie differentially supported beneficial arthropod abundance and ecosystem services, suggesting the type of green space incorporated into urban areas may be an integral component to expanding the conservation potential of urban landscapes.