Lady beetle in the city: Does diet overlap explain patterns of Native Lady Beetle Abundance in urban farms and greenspaces?

View the project final report

Commodities

Practices

• Education and Training: youth education
• Production Systems: agroecosystems

Transforming urban vacant land for agriculture production has been on the rise since the 1890s. Cities that have experienced economic decline that results in an overabundance of vacant land, such as Cleveland, OH, are continuing the trend of urban agriculture. Currently, Cleveland has over 20,000 vacant lots and 235 of these sites have been converted to urban farms and community gardens which address worldwide issues of food security.

However, as urban farmers try to address food security issues, they are faced with the decline in beneficial insects species, such as native lady beetles. These species are needed for the success of agriculture. Since the 1980s researchers have noticed a decline in native lady species which correlates with the introduction of exotic species. The majority of research focused on native lady beetle decline has centered around direct competition, intraguild predation, by exotic species however, if has not been proven in field studies. Exploitative competition, competition for shared resources, is another form of competition that can explain native species decline but it is highly understudied. This form of competition suggest that when exotic lady beetle species reduce a prey base, native lady beetle species will abandon a habitat to forage elsewhere. This implies that the surrounding landscape is likely to affect the supply of beneficial insects. Therefore, I propose to test exploitative competition between native and exotic lady beetle species in order to understand how the composition and management of vacant land influences these dietary interactions among native and exotic lady beetles. My project aims to utilize next generation sequencing tools to: 1)Examine how local habitat management and large-scale landscape composition influences lady beetle abundance and diversity within vacant lots and urban agroecosystems, and 2) measure the dietary breadth and overlap among lady beetle species within vacant lots and urban farms to determine if resource partitioning predicts species diversity within a habitat and how these habitats vary in their ability to support native lady beetle conservation. In short term, my project will contribute to research on conservation of native lady beetle in urban areas. Long term, my project will inform urban farmers and city land managers on the best ways to revitalize urban green space to benefit native lady beetle species that in turn can provide success in urban farms. This will provide economic success in urban cities which can support healthier urban environments and encourage productive urban agriculture.

The long-term goal for my research is to demonstrate if competition with exotic lady beetles explains the decline of native lady beetle species and use this information to design urban habitats to support native lady beetle communities and the biological control they provide to urban agriculture. By the end of the project, urban farmers and Cleveland officials will learn (1) what species of native and exotic lady beetles are found in urban greenspaces and agroecosystems, 2) if competition for food among native and exotic species results in native species declines, and 3) what is the prey diet of the most abundant lady beetle found within Cleveland. A key action outcome will be a factsheet detailing how urban farmers and land managers can take action to conserve native species and their ecosystem services by modifying existing habitats to provide needed alternative prey and other necessary resources.

To distribute knowledge regarding learning and action outcomes I will produce an extension fact sheet and publish a peer-reviewed scientific publication educating readers on the importance of native lady beetles and what can be done to increase their presence. I will also educate owners of urban farms about land management that can be incorporated in their farms to promote an increase in native lady beetle species which in return can promote success in their farms.