Depth distribution of perch stomachs analyzed for the presence of Hemimysis anomala (all campaigns pooled). Each point represents a sampling campaign and its associated depth, with vertical bars showing the depth range of gillnets tracking perch bathymetric distribution. Symbols indicate the detection of H. anomala in perch stomach contents (blue filled circles: present, white open circles: absent by visual inspection, open triangles: absent by DNA analysis). Numbers above points indicate the number of stomachs where H. anomala was present, relative to the total stomachs examined.