Puerto Rico ? A ban on bird imports to Puerto Rico has forced the cancellation of more than 100 cockfights, dealing a blow to a lucrative industry in the U.S. territory, an official said Friday.

Puerto Rico halted all bird imports Thursday after a rare outbreak of avian flu in nearby Dominican Republic, where authorities killed more than 100 chickens, including fighting roosters that tested positive for the lethal virus.

The cancellation of the fights could cost the industry millions of dollars in lost revenue from people who come to watch or enter their birds, said Carlos Quinones, the cockfighting director for the island’s sports and recreation department.

Cockfighting has been outlawed in 49 U.S. states, and Louisiana – the pastime’s last refuge on the U.S. mainland – has approved legislation to make it a crime beginning in August. But in Puerto Rico, the sport is still legal and remains big business.

The island has more than 100 licensed cockfighting pits where roosters peck and kick each other with plastic spurs. About 200,000 fights are held each year, with annual ticket sales of up to $12 million, Quinones said.