The Defense and Interior departments are chipping in $2.9 million to rescue a program preventing an invasive snake species from hitch­hiking rides from Guam to Hawaii and other warm climates on cargo ships and planes.

Congressional earmarks for years paid to control brown tree snakes, a reptile native to Australia and the Solomon Islands that has eaten to extinction nine out of 11 forest birds on Guam since it was accidentally introduced there after World War II.

Scientists fear the snakes would wipe out Hawaii’s many endangered birds if they became established in the 50th state.

Even so, the program was on course to be canceled today — the last day of the current fiscal year — after Congress abandoned earmarks this year. The prospect had alarmed those in Hawaii who try to prevent invasive species from harming the state’s fragile environment, and who are already having a harder time doing their jobs because of state budget cuts.

But the Associated Press learned the program got a last-minute reprieve when the Interior and Defense departments last week signed agreements to fund it for the next nine months. The Pentagon is contributing $2.4 million, and Interior is pitching in $500,000.

“We don’t want a break in service, obviously, and so that’s why there was very much concern over the budget situation,” said Mike Pitzler, who oversees the program as the Hawaii, Guam and Pacific Island state director for the U.S. Department of Agriculture’s wildlife services section.

The departments are committing only to nine months of funding because they are concerned by the cost at a time when all parts of federal government are grappling with budget cuts.

Pitzler said Thursday he would look for ways to restructure and cut costs, but he’s not sure he can do this without affecting the scope of the work.

Sen. John McCain, R-Ariz., and others have questioned over the years why the Pentagon should pay to control snakes on Guam.

The program has been the target of fierce critics of earmarks. In 2009, the Citizens Against Government Waste included brown tree snake control in its “Congressional Pig Book” highlighting alleged examples of government pork-barrel spending.

Pitzler said the vast majority of cargo leaving Guam belongs to the Navy and the Air Force, so it’s natural that the Pentagon pay to screen for the snakes. The program not only protects warm climates like Hawaii and Texas where the snakes would thrive, but also military bases in those states.