A charter boat crew member choked to death after swallowing a bait fish as a joke in front of elementary schoolchildren during a field trip to the Port of Long Beach, authorities said Wednesday.

Jeff Twaddle, 54, of Huntington Beach, “was trying to be lighthearted when he put this thing in his mouth” on Friday, said Long Beach Fire Department Chief Frank Hayes. “But it became an airway obstruction, and he lost consciousness and went into full cardiac arrest.”

Other crew members on board the Gale Force, which had been chartered by the Los Angeles Unified School District to take 20 students on a fishing trip along the breakwater, tried to dislodge the fish and apply CPR but were unsuccessful, authorities said.

Twaddle was taken to St. Mary Medical Center, where he was pronounced dead at 1:15 p.m. Friday, according to Los Angeles County coroner’s Lt. Fred Corral. An autopsy determined that “this was an accident,” he said.

“The cause of death was listed as aspiration of fish.”

School district officials sent letters to parents about the incident and offered crisis counseling to the students who were on board the vessel, authorities said.

louis.sahagun @latimes.com