Can students be the front lines of conservation? A new Canada-wide study, published in Metabarcoding and Metagenomics, suggests they can. The efforts of some 5000 students produced data detailed enough to reveal complex ecological networks hidden inside a small PVC and cardboard tube home.

Cavity-nesting bees and wasps play key roles in pollination and pest control, yet their distributions and feeding relationships are often poorly known because they can be small, secretive and difficult to observe directly. As part of the Bees@Schools community science program, Sage Handler (University of Guelph), Nigel Raine (University of Guelph), and Dirk Steinke (University of Guelph) aimed to address this. They invited schools to volunteer across Canada to install standardised ‘trap nests’ - simple PVC pipe and cardboard tube homes that mimic natural cavities where bees and wasps build nests.

Instead of relying only on traditional identification under a microscope, the researchers used DNA metabarcoding - a method that reads DNA from mixed samples and can detect many species at once. This allowed the team to identify not only which bee or wasp species built each nest, but also which plant pollen or insect prey were brought back as food. The result was a rich, detailed view of both where cavity-nesting bee and wasp species live and how they interact with plants and other insects.

A key outcome of the study was the creation of tripartite networks: maps linking (1) the nesting bee or wasp, (2) its food (pollen or insect prey) and (3) parasites. This kind of network is extremely difficult to build through observation alone, but trap nests can act like tiny ecological time capsules.

Every brood cell contains biological traces and metabarcoding can recover them. Students weren’t just collecting insects, they were collecting entire ecological interaction datasets: the raw material needed to build food-web maps across a whole country!

“A lot of people want to contribute to conservation or learn more about biodiversity, but don’t know how. This shows that a small, practical action, like hosting a trap nest, can contribute real data that researchers can use. Community and citizen science is becoming more common, so keep an eye out for research happening in your neighbourhood.”

- said Handler