Fig 1.
Map of British Columbia, Canada, illustrating sampling locations for 2,655 juvenile Coho salmon by their origin (hatchery based or wild), between 2008 and 2018.
This map was created in QGIS v2.18.13 (http://www.qgis.org).
Table 1.
Thirty-six infectious agents tested on 2,655 juvenile Coho salmon, between 2008 and 2018, along with their overall prevalences (%).
The 31 detected agents are presented in the decreasing order of prevalence.
Table 2.
Frequency distribution of 2,655 collected juvenile Coho salmon samples, by sampling region, year-class, and origin (H: hatchery or W: wild).
Four sampling regions: 1) freshwater-Mainland; 2) freshwater-Vancouver Island (VI); 3) saltwater-east coast of VI; and 4) saltwater-west coast of VI.
Fig 2.
Distribution of the diversity of infectious agents detected in 2,655 juvenile Coho salmon by sampling region and origin (H: hatchery and W: wild) on left side, and the interaction plot for the results of the Poisson regression model, indicating predicted number of detected infectious agents (Y axis) by sampling region and origin (black: hatchery and grey: wild) on right side. Sampling regions: 1) freshwater-Mainland; 2) freshwater-Vancouver Island (VI); 3) saltwater-east coast of VI; and 4) saltwater-west coast of VI. *Statistical comparisons (Bonferroni groups) for predicted diversity between hatchery and wild were only significant in freshwater-Mainland (P < 0.001).
Fig 3.
Distribution of log10-relative infection burden (RIB) of all detected infectious agents in 2,655 juvenile Coho salmon by sampling region and origin (H: hatchery and W: wild) on left side, and the interaction plot for the results of the linear regression model, indicating predicted log10-RIB (Y axis) by sampling region and origin (black: hatchery and grey: wild) on right side. Sampling regions: 1) freshwater-Mainland; 2) freshwater-Vancouver Island (VI); 3) saltwater-east coast of VI; and 4) saltwater-west coast of VI. *Statistical comparisons (Bonferroni groups) for predicted RIB-log between hatchery and wild were only significant in freshwater-Mainland (P < 0.001).
Table 3.
Prevalence (%) and the range of samples tested (N) for the prevalent infectious agents from 2,655 juvenile Coho salmon, by sampling region and origin (H: hatchery or W: wild).
Four sampling regions: 1) freshwater-Mainland; 2) freshwater-Vancouver Island (VI); 3) saltwater-east coast of VI; and 4) saltwater-west coast of VI. For infectious agents’ complete names, refer to key in Table 1.
Fig 4.
Predicted probabilities of the detection of the prevalent infectious agents (Y axes) in 2,655 juvenile Coho salmon by sampling region (X axes) and origin (black: hatchery and grey: wild), based on logistic regression models. Sampling regions: 1) freshwater-Mainland; 2) freshwater-Vancouver Island (VI); 3) saltwater-east coast of VI; and 4) saltwater-west coast of VI. Note that the axes of these graphs are scaled to maximize resolution between hatchery and wild fish. *Significant statistical comparisons (Bonferroni groups) for predicted probability of detection between hatchery and wild, within each category of region, are indicated with asterisks (P < 0.05).