These groups are fairly easy to stop if you have the will. Simply deny entry visas to foreign activists, prohibit domestic activists from receiving outside funding, and procecute violations of the law pertaining to pubilc order. In Ecuador, you can also use an executive decree:

From Wikipedia:

http://en.wikipedia.org/wiki/Rafael_...

On August 3, 2007, Correa ordered the deportation of Sean O'Hearn-Gimenez, director of the Sea Shepherd Conservation Society, saying that he would not allow "gringuitos" ("little white foreigners") to tell Ecuadorians what to do or to persecute local fishermen. Mr. O'Hearn-Gimenez was arrested immediately.[63] The deportation was ordered because Sea Shepherd, in partnership with the Ecuadorian National Environmental Police, exposed and stopped the biggest shark-fin shipment in the port city of Manta -- and O'Hearn-Gimenez had conducted forcible entry against Ecuadorians (thus "interfering with the sovereignty" of the country)[64]. Correa later rescinded the extradition order because O'Hearn-Gimenez was married to an Ecuadorian woman. All the arrested fishermen were released, too, and the confiscated shark fins returned to them. [65] [66] [67]

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ebear