"Effective immediately, Delta will officially ban shipment of all lion, leopard, elephant, rhinoceros and buffalo trophies worldwide as freight," Delta's statement read.
The move follows renewed calls by activists to protect wildlife after American tourist Walter Palmer admitted killing Cecil, the South African lion researchers had been studying for years. Attempts by CNBC to contact Walter Palmer resulted in no response.
Prior to this ban, Delta required cargo to comply with all government regulations regarding protected species, the company said. The airline said it would review policies of other hunting trophies with government organizations.
American Airlines also recently announced a change in policies. The company tweeted Monday night that it "will no longer transport buffalo, elephant, leopard, lion or rhino trophies."
United Airlines also came out against the transport of animal trophies. In an email to The Washington Post on Tuesday, United spokeswoman Jennifer Dohm said that the airline "does not ship" the five animals as freight. "We have not done so previously," she added.
Emirates airline has a ban on hunting trophies of elephants, rhinoceros, lion and tigers, which it instituted on May 15, 2015. The ban is a step "to eliminate illegal trade and transportation of hunting trophies worldwide and save wildlife heritage," according to a statement from Emirates published in National Geographic.