Santiago had a strong respect for nature. He had learned to read natural signs to help him with his fishing. He followed the birds in the sky and the smaller fish of the sea to locate his big fish. However, he hates the Portuguese-man-of-war. When he sees it near his boat, he says,
“Agua mala….You whore.” (pg 35)
“Agua mala” means bad water. The Portuguese-man-of-war was swimming so close to the boat that Santiago could see the tiny fish that were swimming between the filaments. These fish were immune to the poison of the Portuguese-man-of-war, but humans were not. Some of the filaments would catch on the fishing lines of the boats, and when the fishermen brought in the lines, they would still get stung, even when the filaments were no longer attached to the gelatinous body. Santiago would get
“….welts and sores on his arms and hands of the sort that poison ivy or poison oak can give” (pg 36)
The only difference was that the poison of the Portuguese-man-of-war was quick, similar to a whiplash. The old man enjoyed watching turtles eat the agua mala and, after a storm, he loved to walk on the beach and pop them with his feet. However, that practice is NOT recommended by those who know that a Portuguese-man-of-war can sting you with its filaments even after it is dead. There was definitely no love lost there.
Check out the reference below from National Geographic for some stunning pictures of a Portuguese-man-of-war.