As an online petition asking Delta Air Lines to stop transporting exotic animal hunting trophies gathered more than 58,000 online signatures, the carrier responded that it complies with U.S. and international restrictions.

Atlanta-based Delta issued a statement saying it “accepts hunting trophies in accordance with all U.S. domestic and international regulations, which prohibits the possession of trophies or other items associated with protected species.” The airline said customers must provide documentation of trophies to U.S. Customs and Border Protection officials during inspections of their trophies.

Chris Green says in his petition on Change.org that he is a Diamond Medallion frequent flier on Delta and chair of the American Bar Association’s animal law committee, and that he started the petition after South African Airways announced a policy refusing to transport exotic animal hunting trophies, while Delta is the only U.S. airline to serve South Africa directly.