Surveys of Naturally Occurring Leaf Rolls
To characterize the overall community of leaf-sheltering organisms at my study site, I conducted surveys of naturally occurring leaf rolls at Bird Hills from August 23rd-27th, 2022. Surveys were conducted along five 50m linear transects that overlapped with areas previously used for the predation experiment. I pre-established each transect on a digital map of the study site, and used GPS points from the map to start and end the physical transects on-site. I surveyed all plants of a specific height range (over 0.5m and under 2m tall) within one meter of the transect for rolled or folded leaf structures; plants were marked as having either 0, 1, 2, or >3 leaf rolls. Leaf rolls varied in structure but were counted in the survey as long as they were (a) at least partially enclosed, and (b) clearly constructed by an animal. Leaves that were curled due to desiccation or disease were not considered leaf rolls, as I was most interested in the contents of intentionally constructed rolls that resembled structures made by P. troilus larvae.
I recorded the contents of up to 3 leaf rolls per plant by carefully opening each structure by hand. Organisms were visually identified to broad taxonomic groups (e.g., spiders, springtails, beetles). Rolls with either non-living debris or nothing inside were recorded as “empty.” As some organisms immediately jumped or dropped out of the rolls, I also recorded the escape behavior of all observed organisms: jumping, dropping, or no response. In total, I surveyed 464 leaf rolls across 457 individual plants. Of these plants, ~10% were also host plants of P. troilus, including spicebush (Lindera benzoin), sassafras, and tulip tree.