The Old Man and My questions

My friends and I were talking about the book, The Old Man And The Sea, and as usual, arguing with each other about it. One of our arguments were on whether the sharks would really go after the boat after Santiago ties the marlin to the boat. My friend says the sharks would leave it alone after a while in real life because the thing would appear to the shark as alive, since it is moving and fighting back. I say that they would leave it alone because sharks can sense whether or not the body is dead using their energy sensing organs or whatever they have on their nose, and that they would think of Santiago hitting them as some other creature defending it’s kill. I’ll post the other question later.