Fig 2. Average fractional IHNV survival as a function of time from release: April (light blue) and July (purple) curves are due to both UV and natural biota, while biota 1 (red) and biota 2 (green) arise from only the natural biotic decay coefficients of 0.418 day^-1 [11] and 2.30 day^-1 (discussed in Summary).