Dean F. Wilson said this quote

They dived into the ocean of shadow and smog, adding to it with the fumes of their own aircraft. The goggles were useless now, but Jacob kept them on, in case there might be some break in the murky pool. It was fitting that the Worldwaker had passed through there, with the shark emblem painted on brightly. In those deep waters it could not be seen. It almost felt like it had lured them in. The dolphins do not hunt the sharks.