Customs and Border Protection Office of Field Operations, the agency that oversees the ports of entry, already had a shortage of 3,700 officers. That was before record numbers of asylum-seekers started arriving at the southwest border. Then that shortage was made worse.

Tony Reardon is president of the National Treasury Employees Union. He says CBP officers were at first asked to volunteer for work on the Mexican border.

"Now they are drafting officers from ports around the country," he said.

The coalition of governing boards and private companies will ask the Senate Appropriations Committee on Wednesday for funding requested by the Trump Administration to fill those slots.

The group's letter to the committee cited increased wait times, less mandatory training for officers and even impacts on cruise ships if the shortage and re-deployments continue.

"For instance, U.S. international hub airports like Chicago-O’Hare, New York’s John F. Kennedy, Los Angeles International, San Francisco International, and Atlanta Hartsfield-Jackson International routinely saw wait times for non-U.S. citizens to clear Customs and Immigration of two and three hours since the beginning of April," the group wrote.

Seven hundred thirty-one officers were temporarily redeployed to the border.