A six-foot shark was circling the boat and, Teitoi said, bumping against its hull.

"He was guiding me to a fishing boat," Teitoi said.
Гммм, вероятно, акула не настолько приводила чувака к рыбакам, насколько он плыл вслед за акулой, которая ощущала рыбки в сети.

I mean to say: Most likely, the shark was not so much "guiding" the dude to the fishermen, so much as the dude was following after a shark, that had sensed some small fish caught in a net.

This seems very different from, for instance, the famous 19th-century case of some Australian killer whales who evidently taught themselves, by trial-and-error, how to guide human whaling boats towards groups of baleen whales, and also to "herd" the baleen whales into the harbor so that the human harpooners could kill them more easily. Which meant that both the orcas and the humans were able to obtain more whale-flesh with less work. (Essentially, these orcas functioned as "hunting dogs," but unlike dogs, they weren't bred and trained by humans for such work -- сами собой выдрессировали себя!)