D3353: Subterranean arthropod sampling of agricultural ditches on the Delmarva peninsula: A comparison of techniques

Semi-natural habitats are common throughout agroecosystems on the Delmarva Peninsula and the arthropods within them provide beneficial ecosystem services such as decomposition, bioturbation, and biological control. These areas usually possess a more stable and diverse environment than neighboring arable fields, conserving valuable niches and habitats for beneficial arthropods. This study investigates the carabid beetle larvae and subterranean arthropod fauna of semi-natural habitats on the Delmarva Peninsula using subterranean pitfall traps. We also investigated the efficiency of two styles of subterranean pitfall traps. Twelve, 1.5ft deep traps with a perforated design and twelve 1.5ft deep traps with a horizontal slit design were baited and equally distributed throughout 4 semi-natural habitats on 1 farm. Samples were collected every 2 weeks beginning in September 2023. Observing carabid larval identity within ditches will provide information about which genera utilize ditches for reproduction, and sampling throughout the year could reveal overwintering patterns. When comparing trap types, we expect to find a higher diversity of arthropod families in traps with perforations and higher abundances of certain taxa in traps with horizontal slits as subterranean arthropods may inhabit specific depth ranges and hole area is distributed differently between traps. Understanding how carabid beetles use agricultural ditches has important implications for conservation biological control within adjacent cropland. Additionally, developing the most effective trap design is crucial for studying subterranean fauna and understanding the diversity and ecological roles of soil arthropods within agroecosystems.