- The best know trait of humpback whales is called the breach, when they jump high out of the water in an acrobatic movement and slap back down. - Scientists aren't positive why they do this, but they believe it is either a form of communication, intimidation or a way to remove parasites. Whatever the reason, breaching is contagious and when one whale does it, the rest follow. - Another trait of the humpback whale is pectoral fin slapping on top of the water.