Austin, Texas - Hunting clubs and a man who paid $350 000 (about R4.5-million @R13.09/$) for a license to hunt a black rhino in Namibia have sued Delta Airlines, saying its ban on transporting some big game hunting trophies hurts conservation efforts and violates its global obligations.
READ: Largest Airline in the world stops transporting hunting trophies
In a lawsuit filed in federal court in Texas on Thursday, the hunter of the endangered black rhino, Corey Knowlton, along with the Dallas Safari Club, the Houston Safari Clubs and others said that the transport of the trophies is allowed under a strict systems of global permits and Delta must abide by its obligations.
WATCH: US hunter finally bags his black rhino in controversial conservation hunt
"Tourist hunting revenue is the backbone of anti-poaching in Africa. If there are fewer users, as Delta's embargo envisions, there are fewer boots on the ground and reduced security for elephant, rhino and other at-risk wildlife," the lawsuit said.
Delta officials were not immediately available for comment.
Delta was one of three US airlines in August that banned the transport of lion, leopard, elephant, rhino or buffalo killed by trophy hunters, in the fallout from the killing of Zimbabwe's Cecil the Lion about a month earlier.
READ: Airlines send trophy hunting industry into a tailspin
Delta is the only of the carriers with direct service between Johannesburg and the United States and its decision was seen as carrying the most weight.
There has been an international outcry against trophy hunting among animal lovers since it emerged that American dentist Walter Palmer killed Cecil, a rare black-maned lion that was a familiar sight at Zimbabwe's Hwange National Park.
Eleven African countries issue lion hunting permits. Of them South Africa's hunting industry is the biggest, worth $675 million a year, according to the Professional Hunters Association.
READ: SAA told to stop enabling trophy hunters
Hunting groups argue the money generated from the legally sanctioned hunts bolster the coffers for conservation in emerging African countries that want to use their limited finances for social programs.
In the middle of this year, the cargo division of South Africa's national carrier, SAA, lifted an embargo that had been in place since April on the transport of legally acquired hunting trophies of African lion and elephant, rhinoceros and tiger.
"It should be remembered that hundreds of legally acquired wildlife specimens, such as hunting trophies, pass through our main ports of entry and exit monthly without incident. Penalizing an entire industry for the illegal actions of the few is not in the country's best interests," South Africa's Environment Minister Edna Molewa said at the time.