Stream tributaries exhibit habitat heterogeneity from vegetation cover, hydrology, and channel morphology. Human land-uses (i.e. housing development, agriculture, industry) can degrade riparian buffers and impair water quality. Aquatic insect life cycles respond to water-quality changes, particularly higher temperatures that hamper metabolically taxing change from the immature to adult life stage. Mayfly life traits permit higher population densities in cool microhabitats created by riparian vegetation during elevated summer temperatures. However, whether riparian restoration creates equivalent microhabitats for emerging adults remains unknown. Our study compared water quality and insect emergence between upstream unrestored (UR) and downstream restored (R) sections of Stroubles Creek in Blacksburg, Va, a tributary of the New River, to determine how light, temperature, and vegetation affect insect emergence timing and abundance. We predicted that light and water temperature would be similar between sections during fall and winter, but lower in the restored section during late spring and summer when vegetation is denser and air temperatures are warmer.
We divided a 1.5-km section of Stroubles Creek within the StREAM Lab at Virginia Tech into two sections: UR, with sparser and more herbaceous vegetation, and R, with restored riparia of sapling trees planted in 2010. Four replicate cross-sections were established in each section. Light and temperature sensors collected data at 15-min intervals from March 24th to October 31st, 2025. Floating insect emergence traps were deployed at each cross-section during the same dates, with samples collected every 7-9 days. Insects were classified to order, counted, and analyzed for total emergence and proportion of non-dipterans per day. Through June, the UR section had slightly lower temperatures despite 2% lower light levels in the R section. Algal growth or stream morphology variations may explain this discrepancy. The UR section exhibited greater insect emergence (26 versus 18 insects per d), likely due to greater algae and warmer spring temperatures. Analysis of non-dipterans and water conditions from July-October 2025 is ongoing. Understanding how riparian restoration affects microhabitat temperature and dissolved oxygen impacted by land development and climate shifts is critical for implementation of effective conservation practices.