Fish and invertebrates will be collected from all sites (C-I) on a quarterly basis, according to expected natural and drain water flow regimes. Sampling will occur in March (high flow), June (early summer irrigation), August (late summer irrigation), and November (low flow). This schedule will also facilitate taking biota samples to reflect temporal changes in drain water constituents. Pre-discharge baseline samples will be collected in the quarter preceding initial drain water discharges to Mud Slough.

Because aquatic insects are a major source of food for certain avian species during the breeding season, insect samples will be collected in the spring. Baseline waterfowl egg samples will be collected in spring along the Mud Slough corridor and in the future when indicated. Also, aquatic vegetation will be sampled in late summer (August) to evaluate contaminant loading in plants known to be consumed by waterfowl.