When on the boat looking at the monitor during close-up shots, there is a boat and a large mass moving through the water. When panned out, the screen is clearly on, but there is no picture. But when they go back into close-up, there is the boat and large mass on the screen again.
Whip states the largest whole squid carcass ever found was 45 feet long, and that no one knows how big a squid gets. While the first statement is not strictly true, it could be Whip's error; the second statement is true, since squid are not generally visible.