Amid global uproar sparked by the killing of Cecil the lion by American trophy hunter Walter Palmer, three major U.S. airlines—Delta, American and United—have followed in the footsteps of several international carriers and announced bans on the shipment of lion, leopard, elephant, rhinoceros and buffalo, otherwise known as the "African Big Five."

Airlines play a major role in trophy hunting as it allows hunters to bring home their "prize." Animal advocates have long been pressuring carriers to change their policies, even before Cecil died at the hands of the Minnesota dentist in Zimbabwe. A Change.org petition launched three months ago, and signed by nearly 400,000 people, urged Delta specifically to enact this shipment ban, since it's the only U.S. carrier with direct service to South Africa (which has the largest hunting industry in Africa, according to The New York Times).

"Last year, more than a thousand rhinos were poached in South Africa, elephant populations have plummeted 66 percent in just five years and the export of lion 'trophies' has increased ten-fold—hunters bringing home animals' heads and bodies to stuff and mount," the petition states.

Petitioners urged Delta to follow after South African Airways (SAA), which had banned all transport of exotic animal cargo this past April, and prompted Emirates, Lufthansa and British Airways to enact similar bans soon after, according to the Times.

Then, following the international outrage of the beloved Zimbabwe lion's death, several foreign airlines—Air France, KLM, Iberia, IAG Cargo, Singapore Airlines and Qantas—announced a ban on shipments of exotic animals last week.

Cecil has brought to light the role airlines play in transporting trophy kills as cargo: http://t.co/a4y2dxXD5x pic.twitter.com/be7qyBTdyB

— NY Times Travel (@nytimestravel) August 3, 2015

In a domino effect, three top U.S. carriers have now joined the growing movement. It's a significant victory for those opposed to trophy hunting, as the 15,000 American tourists who visit Africa on hunting safaris annually make up the majority of non-African hunters, the Times reported.

"Effective immediately, Delta will officially ban shipment of all lion, leopard, elephant, rhinoceros and buffalo trophies worldwide as freight," Delta announced Monday afternoon. "Prior to this ban, Delta's strict acceptance policy called for absolute compliance with all government regulations regarding protected species. Delta will also review acceptance policies of other hunting trophies with appropriate government agencies and other organizations supporting legal shipments."

American Airlines sent out this tweet Monday night:

Effective immediately, we will no longer transport buffalo, elephant, leopard, lion or rhino trophies.

— American Airlines (@AmericanAir) August 4, 2015

And today in a report from The Washington Post, United spokeswoman Jennifer Dohm said that the airline “does not ship” the five big game animals as freight and “we have not done so previously.”

Read page 1

“United also follows all U.S. domestic and international regulations, which prohibits the possession of trophies or other items associated with protected species,” she added. Big game shipment is now officially prohibited by United moving forward.

The policy shift from Delta, American and United was praised by Wayne Pacelle, president and CEO of the Humane Society of the United States. “Lions, elephants and the other species that make up the Africa Big Five belong on the savanna, not on the walls and in home museums of wealthy people who spend a fortune to kill the grandest, most majestic animals in the world,” Pacelle said in a statement yesterday. “Delta has set a great example, and no airline should provide a getaway vehicle for the theft of Africa’s wildlife by these killers.”

Meanwhile, pressure is building to bring justice to Cecil's grisly killing by Palmer, who is currently in hiding. Zimbabwe is seeking the extradition of the 55 year old, who allegedly paid $50,000 to shoot, kill and behead the famous lion.

VIDEO: Zimbabwe wants American hunter to face charges for killing #Cecil the lion. http://t.co/dxtPVrwGjj pic.twitter.com/Z3a1pOqG20

— Reuters Top News (@Reuters) July 31, 2015

As Reuters noted, a million-signature-strong Change.org petition is urging the U.S. Fish and Wildlife Service to list African lions as a threatened species and punishment for those involved in Cecil's death. While including the African lion to the U.S. list would not stamp out trophy hunting, it does require a permit from the service to import lions or their body parts to the U.S., Reuters pointed out.

The Times reported that the current lion population has dipped to 35,000 (compared to 100,000 a century ago) and dropped considerably in the last three years, prompting the U.S. Fish and Wildlife Service to propose listing the lion as a threatened species.

While efforts from these airlines to stamp out trophy hunting should be applauded, it doesn't eliminate the problem entirely. Unfortunately, South African Airlines—which helped kick start the exotic animal import ban—"lifted a ban on the transportation of animal-hunt heads and carcasses in its aircraft," Bloomberg reported.

And just today, The Guardian reported that on July 6, customs officials at Zurich airport seized 578 pounds of illegal ivory being transported from Tanzania to Beijing via Zurich. It's estimated that the contraband might have come from up to 50 elephants and worth 400,000 Swiss francs (roughly $410,000) on the illegal market.

YOU MIGHT ALSO LIKE

5 New Developments in the Killing of Cecil the Lion

What the Killing of Cecil the Lion Has in Common with the Slaughter of Pilot Whales

7 Photos That Show Why Dogs Are Elephants’ Best Friends