Orcas' calculated attacks on boats raise concerns.

Boat captain Dan Kriz has experienced two ambushes by pods of orcas, with the second attack seeming more targeted. The orcas bit off both rudders and seemed to know exactly what to do to prevent the boat from traveling any farther. Kriz is one of several people to experience encounters with orcas off the coasts of Portugal and Spain in recent months. The reason why killer whales have been ramming into boats remains a mystery, but incidents have more than tripled in the past two years.