Clubbing sea lions to death

Yesterday, the Associated Press reported that 53 sea lions in the Galapagos Islands had been clubbed to death.  The deaths were reported as having to have been caused by humans.  Having recently visited the Islands, I can certainly attest that these animals are not afraid of the world’s most dangerous predator and were easy targets, but why and who?  The Ecuadorians are investigating the killings; however, I am not optimistic that we will learn who committed the crimes, unless someone reports that they know who killed these sea lions.  The islands are open and accessible by boat with some islands inhabited by people. 

Why such a senseless and cruel act?  Was this an insane effort to hurt the tourism business which is criticized for changing the ecology of the area?  Just some random lunatic?  How do you protect the Islands without changing them?

Truly a horrible story.