They were paludromous, to invent a term. They were swimming marshward to survive. This very exigency the drying up of pools and puddles was what drove the evolution of the lungfish and walking fish and mudskippers, but great expanses of geological time were required for that. The carp had only days. Their desperation to reach the marsh suggested that time was running out for them.
Carpe diem indeed.
Either bank of the rivulet had been scooped out and undermined by the urgent wriggling of their bodies. It was a form of attrition new to me. As the water in a restored wetland north of San Francisco subsides in spring, fish are stranded, scavengers feast and nature follows its inevitable course. The headwall of the narrowing, carp-carved arroyo was in the triangular shape of the head of carp. There was room only for a single fish there, at the apex of the carp pyramid, and it was always a large one.