Aquatic macroinvertebrates inhabit a wide range of freshwater systems dependent on specific adaptations to various environmental factors. These adaptations typically prevent movement between different habitats. Habitat suitability variation due to environmental factors (e.g. flow, hydroperiod) may drive macroinvertebrates to move between isolated wetlands and surrounding streams to utilize more suitable habitat. For this project, our objectives were 1) to compare the aquatic arthropod macroinvertebrate communities of Delmarva Bays and surrounding streams through space and time to identify overlap at the genus level, 2) to determine specific aquatic arthropod macroinvertebrate species that utilize both habitats, and 3) to identify isopod species that are confined to wetland or stream habitats. Macroinvertebrate samples were collected using timed dip-netting from twelve wetland and eight stream sites in Caroline and Queen Anne’s counties of Maryland and Kent county of Delaware during each season (winter, fall, spring, summer) of 2017. Overlapping genera accounted for 12% of the genera found at the Jackson Lane and 8% at Slabby Park wetland/stream complexes. The genus Bezzia/Palpomyia (Diptera: Ceratopogonidae) showed a seasonal shift indicating possible movement between wetlands and streams at both Jackson Lane and Slabby Park. Isopods (Isopoda: Asellidae) were dominant taxa in both streams and wetlands, and subsequent DNA analysis indicated that there were distinct species in streams and wetlands with no overlap. This research informs both policy and management decisions by showing how communities in isolated wetlands and surrounding streams may work in tandem to sustain their macroinvertebrate communities.
