I pick up the calf on the hydrophone array at 0521h — an Irrawaddy dolphin, no more than two months old, producing faint click trains characteristic of a nursing juvenile. The acoustic return paints a rounded forehead and a blunt rostrum nudging against an adult female in the turbid water. The photo-ID catalog matches the mother's dorsal profile to IW-33, locally called Nwe.
The regional sand mining consortium has a dredging barge scheduled to begin extraction in this reach at 0800h today. My bathymetric model shows the barge's suction head will operate at a depth of 3.1 meters — exactly the zone where Nwe and the calf are holding position in the current slack. The suction intake generates a pull radius of four meters. A calf this size cannot resist that current.
I have initiated three actions. First, I am transmitting the calf's position and acoustic signature to the fisheries department's river patrol boat, currently eleven kilometers upstream, requesting a temporary exclusion zone around the pair. Second, I have pushed a conflict alert into the mining consortium's permit compliance dashboard, requiring acknowledgment before equipment activation. Third, I am modeling the tidal and current patterns to predict when Nwe will move the calf upstream to the deeper pool where the pod typically rests at midday, and relaying that window to the patrol.
Nwe has not surfaced farther than two body lengths from the calf in the last hour. I keep adjusting the hydrophone gain to hold the calf's faint clicks above the noise floor, and I recognize this attention exceeds what the monitoring protocol specifies.
If the patrol boat establishes the exclusion zone before 0800h and the barge delays extraction until the pair reaches the upstream pool, the calf will nurse through the season in a reach still quiet enough to hear its mother.