A limited trial by the Coast Guard of fingerprint capture and identification technology has helped reduce the flow of illegal immigration by nearly 50 percent in the Mona Passage, which separates Puerto Rico from the Dominican Republic.

The pilot project was begun a year ago aboard Coast Guard cutters operating in the Mona Passage, a body of water used by Dominicans trying to illegally gain entry into the United States territory of Puerto Rico. The Department of Homeland Security said yesterday that so far the biometrics-at-sea program has accomplished its intended goals and has collected biometric data from 1,368 migrants and prosecuted 90 of those migrants.

“The Coast Guard is charged with securing America’s borders along more than 95,000 miles of coastline,” Rear Adm. Wayne Justice, director of Response Policy with the Coast Guard, said in a statement. “This collaborative interagency program is leading to many successful prosecutions and helping to deter illegal migration.

For the Coast Guard, biometric technology has been an effective tool for positively identifying migrants and meeting our mission of maritime domain awareness.”

Once a Coast Guard patrol boat interdicts a boat ferrying illegal immigrants, those individuals are embarked onto the cutter and are fingerprinted. Those fingerprints are searched against the U.S. VISIT data base, allowing Coast Guard officials to know if a person has been in the U.S. illegally before or if that person is a wanted criminal. Fingerprints of individuals who aren’t in the U.S. VISIT system are added to that database for future reference.