Nature tracks crocodile migrations, showing how they get around by surfing:
Zoologists didn’t know how the reptiles travelled such long distances given the sustained level of swimming required.
The answer is that the crocodiles ride surface currents, says a group led by Craig Franklin, a zoologist at the University of Queensland in Australia. The reptiles only travel when the current flows in the direction of their desired journey, the researchers report.
…“They know when the current is flowing in the direction they want to travel,” says Franklin. “It is like they are purposeful. They seem to be making a decision prior to the journey that they will travel with the current.”
…
The latest study indicates that surfing the ocean currents is an effective migration method for estuarine crocodiles. Surfing also provides a way for individuals from distant populations to cross ocean barriers and breed, helping to explain why estuarine crocodiles have not diversified into different species.
I’m betting localism wasn’t a problem for these guys.