I used to think of a food web as a network of organisms and interactions following simple biological rules. Now I think of a chaotic sampling blitz of every microhabitat in an ecosystem. Amidst the mayhem, the lights of these Berlese Funnels shone peacefully, passively sorting samples.
Berlese Funnels passively sample plant, soil, and litter matter. Each funnel contains a mesh screen, light, and collecting vial. We place samples on the screen and arthropods in the sample flee the light and fall into the collecting vial. These funnels, set up in a building called The Breezeway, processed over 1,500 samples this summer. These samples are part of a project to build food webs on Palmyra Atoll. Food webs include species identity, abundance, and biomass data, linking community composition to ecosystem-level energy cycling. Because of sampling intensity, constructing a food web in any environment is a daunting task. Even biologically simple systems like Palmyra are complex – the atoll’s 150 species of plants and animals might have upwards of 2.2 x 104 species interactions.