Poster Presentation Society for Freshwater Science 2025 Annual Meeting

Investigating Trends in Aquatic Insect Emergence to Understand Aquatic-Terrestrial Nutrient Cycling (117793)

Erin Chen 1 , Heili Lowman 1 , Tamera Wooster 2 , Tyler Edwards 1 , Chris Solomon 2 , Emily Bernhardt 1
  1. Duke University, Durham, North Carolina, United States
  2. Cary Institute, Millbrook, New York

The emergence of aquatic insects play an important role in the transfer of nutrients from the aquatic environment to the terrestrial environment (Schindler & Smits, 2017). Shifts in water temperatures, chemistry, and flow can all impact the size, quantity, and time frame in which insects emerge, which may in turn result in a phenological mismatch between the emergence of aquatic insects and their terrestrial predators (Baranov et al., 2020; Leathers et al., 2024; Shipley et al., 2022). To examine how the time frame of peak insect emergence and counts of insects change, sticky traps were set up to capture emerging insects at 8 stream-adjacent sites in the Hubbard Brook Experimental Forest (HBEF), where researchers have carried out numerous environment-altering treatments to study the impacts on the watershed ecosystem using continuous water chemistry data (Holmes & Likens, 1999). We developed an online interactive dashboard that allows users to explore peak emergence dates by year and counts of insects at emergence by date range, taxa, and site. Since weekly record-keeping began in 2018, over 260,000 aquatic insects have been identified across the HBEF streams, with clear peaks in dipteran emergence during both spring and fall seasons. Monitoring insect emergence time and count, coupled with existing water chemistry and flow monitoring, is critical for developing a further understanding of how changes in the aquatic ecosystems impacts nutrient cycling between the aquatic and terrestrial ecosystems.

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