The German justice system will entertain a Costa Rican request to extradite controversial Sea Shepherd conservationist and "Whale Wars" star Paul Watson, but he can post bail while the matter is considered, a Frankfurt court ruled Friday.

Bail for Watson -- who faces what his organization and attorney allege are politically motivated charges over a 2002 confrontation at sea with Costa Rican fishermen -- was set at 250,000 euro ($318,000), Frankfurt high regional court spokesman Ingo Nohre said.

Watson, 61, intends to post it Monday, his group said.

Watson, whose attempts to disrupt Japanese whalers at sea gained fame through Animal Planet's "Whale Wars" TV show, was detained last weekend at the Frankfurt airport after Costa Rica issued an international request for this arrest.

Costa Rican authorities allege that Watson's crew aboard Sea Shepherd's Ocean Warrior ship endangered a Costa Rican fishing vessel during a confrontation off Guatemala's coast, according to the Frankfurt court.

The court ruled Friday that Germany will consider the request, and that Costa Rica will have 90 days to make its case. The German Ministry of Justice then will decide whether to extradite Watson.

The U.S.-based Sea Shepherd, which denies the allegations, has urged supporters through its website and social media to write to German officials, arguing that the charges have less to do with law than with Watson's anti-conservationist enemies, and that it doubts he would get a fair trial.

"As Sea Shepherd becomes increasingly more effective at protecting marine wildlife globally, the enemies of the oceans are using all of their resources to stop us," the group said in a statement. "... (The extradition request) we believe stems from Sea Shepherd victories in curbing shark finning on the high seas."

Thousands appear to have written to German officials so far, Sea Shepherd ship operations officer Peter Hammarstedt said, citing anecdotal evidence, including supportive e-mails the group received.

Hammarstedt said the Ocean Warrior found the Costa Rican crew killing sharks for their fins in Guatemalan waters in 2002, and it initially had permission from Guatemalan authorities to stop it and tow the vessel into port.

The Ocean Warrior used water cannons on the fishing vessel in an effort to stop it, but "there were no injuries and no physical damage to any ship," Hammarstedt said.

The Ocean Warrior succeeded in stopping the ship, but Guatemalan authorities eventually asked Watson to release it, Hammarstedt said.

The confrontation is detailed in part of a 2006 documentary, "Sharkwater," Hammarstedt said.