Aquatic macroinvertebrate density in headwater streams with varying intensities of riparian Amur honeysuckle (Lonicera maackii) invasion
Headwater streams in the midwestern United States are an important ecosystem because they are home to key macroinvertebrate species and serve as the starting point for freshwater river systems. According to the river continuum concept, any terrestrial inputs to headwater streams can influence biotic communities and abiotic conditions downstream. Amur honeysuckle (Lonicera maackii) is an invasive shrub species prominent in the midwestern U.S. whose allelopathic properties have proven detrimental to local species biodiversity. We hypothesized that increasing Amur honeysuckle density along headwater streams would alter the diversity of aquatic macroinvertebrate communities. Five sites located in Montgomery and Miami Counties, Ohio were chosen to represent varying Lonicera maackii density along the banks of headwater streams: one heavily invaded site, two moderately invaded sites, and two reference sites (little to no invasion). A 30-meter section of stream at each site was divided into five plots that were six-meters long and were used to sample aquatic macroinvertebrates for five consecutive seasons. A dip net was moved across each plot for 60 seconds, and macroinvertebrates were then separated from the collected debris, preserved in alcohol, and brought back to the lab where they were sorted into taxonomic groups. The total number of macroinvertebrates collected did not vary greatly among sites within each season. A preliminary assessment of community composition showed that there was a greater relative abundance of Diptera and Oligochaeta at the heavily-invaded site in fall and winter compared to the moderate and reference sites. The relative abundance of Trichoptera was lower at the heavy site than the moderate and reference sites in fall, spring, and summer. Further analyses are required to understand how community composition varies among the sites and how such differences relate to honeysuckle invasion and macroinvertebrate feeding mechanisms.
Ryan W McEwan
Primary Advisor's Department
Stander Symposium poster
"Aquatic macroinvertebrate density in headwater streams with varying intensities of riparian Amur honeysuckle (Lonicera maackii) invasion" (2018). Stander Symposium Posters. 1371.