Figure 1

Infection clusters for the marine-transmitted microsporidian, Loma salmonae, occurred for all host species but prevalence was greatest in Coho salmon. The color of 30 km hexagons indicates L. salmonae prevalence while empty cells indicate that samples were collected but the pathogen was not detected (0% prevalence). Red circles indicate positive clusters (significantly higher than random likelihood of infection or infection intensity). Blue circles indicate significantly lower than expected regions of infection. Similar maps for 40 other pathogen taxa are available in Supplementary Material 1. Basemap data are from the GSHHG (Global Self-consistent, Hierarchical, High-resolution Geography) Database³⁸. The coordinate system for the data is WGS 1984 and the maps are projected in NAD 1983.