A flock of whooping cranes grounded for nearly a month by red tape can continue their flight to their winter home in Florida thanks to a special exemption from the federal agency that mired their journey in the first place.

The Federal Aviation Administration (FAA) on Tuesday provided a one-time waiver to Operation Migration, the conservation organization that was leading the cranes on their 1,285-mile journey from Wisconsin to Florida in an effort to teach young birds of the endangered breed how to make the flight.

The organization had voluntarily halted the crane's flight about 693 miles in late last year after being warned by the FAA that they were possibly violating an agency regulation that forbids paying salaries to pilots who fly the small, ultralight aircraft used to guide the birds.

FAA regulation dictates that "sport pilot aircraft" cannot be used for commercial purposes, and Operation Migration's paying its pilots made the flights commercial, the agency said.

The cranes, nine in all, had been held in a pen in Franklin County, Ala., since mid-December, while advocates lobbied the FAA on their behalf.

More than 1,400 people signed an online petition asking that the flight be allowed to continue, and the organization appealed to the FAA directly that pilots behind the crane's journey are full-time employees of the organization who do the flying on a volunteer basis.

The FAA first accepted the explanation but then reversed its decision and said Operation Migration was not meeting the requirements.

On Tuesday, the agency changed its mind again, ruling, in this one instance, the birds should not be grounded.

"Because the operation is in 'mid-migration,' the FAA is granting a one-time exemption so the migration can be completed. The FAA will work with Operation Migration to develop a more comprehensive, long-term solution," read an FAA statement.

The birds will now continue their journey to their winter retreats, the St. Marks and Chassahowitzka national wildlife refuges in Florida, where they will be met by at least one crane who managed to evade the bureaucracy and start his winter escape early.

Conservation Migration reports this year's journey actually began with 10 cranes, but winnowed down to nine when one took a wrong turn, that turned out okay.  The crane was later found with a flock of migrating sandhill cranes and has already arrived in Florida.

The Associated Press contributed to this report.