Where water meets land: Empowering students and citizen scientists to investigate aquatic insect emergence
Traditionally, exploration of the aquatic-terrestrial interface has emphasized directional inputs from land to water. However, a new body of ecological understanding has characterized reciprocal interactions and draws attention to fluxes from water to land, including the emergence of adult aquatic insects that serve as prey for terrestrial predators. We present a guide for an inquiry-based outreach activity and collaboration between stream ecologists and students. The focus is on ecosystem interactions; specifically, “What is the role of insect emergence in connecting aquatic and terrestrial ecosystems?” We employ a constructivist approach. First, a pre-lesson is delivered in the classroom; second, a field investigation is carried out to highlight differences between prior knowledge and new knowledge. Specifically, insect emergence is studied using floating traps distributed along a stream reach. Insects are collected, identified, photographed, and released. Observations of riparian insectivores (e.g., birds and spiders) are photo-documented and counts recorded. Finally, a visual report of the insect and predator assemblage is created to apply new knowledge; reports are shared via a regional database to reflect on learning. This study meets Next Generation Science Standards of the Disciplinary Core Idea “LS2A: Interdependent Relationships in Ecosystems,” and we provide suggestions for adaptation to multiple grade levels.
The interface between aquatic and terrestrial ecosystems is bridged by many flows of materials and organisms; this complex web of processes continues to be untangled by scientists. New knowledge can be effectively distilled through novel teaching tools, as this investigation demonstrates. The data are largely qualitative: an interactive photo-collage is constructed by overlaying images of stream insects and riparian insectivores onto a base map of the sampled stream reach. Insects are identified at the family level, and count data are included with the imagery. The photo-collage is a unique alternative to the traditional laboratory report that demonstrates the power of mapping in scientific investigations and encourages students to work collaboratively.
This activity will be applied to Idaho’s Portneuf River Watershed, engaging a local elementary school. In the future, classes will be able to register online as citizen scientists for the Portneuf Watershed Partnership, and submit their images to a database of photo-collages. We expect contributions from streams throughout the Portneuf Valley to increase the spatial extent of the data. If conducted seasonally and annually, this activity can reveal temporal heterogeneity in organism assemblages and explore how the timing of insect life cycles drives ecosystem-level processes.