Dataset: Geange_and_Stier_2010 Charismatic Microfauna Trophic Cascade
Deployment: Osenberg_et_al_Moorea

All experiments were conducted in plastic containers (190 mm x 190 mm x 90 mm; W x L x H). To allow the exchange of fresh seawater,  approx. 80% of the surface area of the lids, and two opposing sides of containers were cut away and covered with 0.5 mm mesh screening. Containers were placed within large (2,670 l) outdoor flow-through seawater tanks (10 containers per tank). In each experiment, sea hares (Stylocheilus striatus), nudibranchs (Gymnodoris ceylonica), and cyanobacteria (Lyngbya spp.) were collected from the field. Prior to experiments, nudibranchs were starved for 3 days, and cyanobacteria were rinsed with filtered seawater, which removed associated flora or fauna.

The presence of a trophic cascade was examined using three treatments: (1) cyanobacteria alone (n = 16); (2) cyanobacteria and sea hares (n = 8); (3) cyanobacteria, sea hares, and nudibranchs (n = 8). Cyanobacteria (mean = 78.0 g, SD = 12.9) were added to each of the 32 containers. Ten sea hares (mean length 57.4 mm ± 5.6 SD) were added to containers assigned to treatments 2 and 3, and one nudibranch (mean length 48.6 mm ± 3.6 SD) was added to containers assigned to treatment 3. Each morning (*0700), the number of surviving sea hares in each container was recorded. Nudibranch densities were maintained at their original density by replacing any missing or dead nudibranchs throughout the duration of the study (two nudibranchs were replaced on day two, and no other replacements were necessary). After 4 days, cyanobacterial biomass (g) and the number of sea hares in each container were recorded.