The airport in Honiara, the capital of the Solomon Islands, was on high alert on Monday
because of protests against the export of up to 200 live dolphins.
Wild dolphins are loaded onto a plane bound for Mexico
Police blocked the airport with a huge security cordon, and ordered journalists not to take photographs as a Brasil Air DC-10
cargo jet arrived to take the bottlenose dolphins to the tourist resort of Cancun on Mexico's Yucatan Peninsula.
Villagers in the near-bankrupt Pacific state are reported to have sold them to an international syndicate for about $400 (US$265) each.
Britain's envoy to the island nation, Brian Baldwin, says the huge profit margin means high-ranking Solomons officials are likely to be involved.
"That sort of money would have inevitably attracted some big players here," he told The Associated Press news agency.
Animal rights activists tried to block the export of the dolphins, which are thought to be destined for a life as performing
animals in Mexican aquatic parks.
Australia's Environment Minister David Kemp last week called on Mexico to honour a treaty it had signed on International Trade in Endangered Species of Wild Fauna and Flora, which states the importation of the mammals is illegal.
But the call was rejected by the Mexican Government, which said Parque Nizuc - the marine park running the operation - had
the correct documentation.
Nicola Beynon, a Humane Society International campaigner, said the chances of all the animals surviving the mammoth journey
Campaigners say captured dolphins suffer stress and refuse to eat
"Such a massive capture of dolphins is unprecedented and will inevitably lead to debilitated and dying animals," she said.
The businessmen arranging the dolphin shipment could not have picked a more high-profile moment.
The dolphins' air freighter arrived just minutes before an Australian air force Hercules, which was carrying a group of advisors ahead of the arrival of an Australian-led intervention force later this week.