From CNN.com: 'Uncontacted tribe' sighted in Amazon

Researchers have produced aerial photos of jungle dwellers who they say are among the few remaining peoples on Earth who have had no contact with the outside world.

Taken from a small airplane, the photos show men outside thatched communal huts, necks craned upward, pointing bows toward the air in a remote corner of the Amazonian rainforest.

Shouldn't there be some kind of Star Trek non intervention "Prime Directive" be in play here?  Buzzing the primitives with a giant noisy bird causing them to point bows at you somehow doesn't seem to be the proper thing to do.