The Troubles Tracking Abducted Girls in Boko Haram's Nigerian Forest

May 7, 2014 — -- The search for the nearly 300 teenage girls abducted from a school in Nigeria three weeks ago could soon enter a new phase with the addition of a team of American “coordinators” on the ground, but former U.S. diplomatic and law enforcement officials say that with so much time passed, and in such vast and hostile terrain, the task before them is daunting.

While neither Nigerian nor American officials know where the girls are now, they were believed to be taken to the stronghold of the terror group Boko Haram in the northeast of the African nation, perhaps into the Sambisa Forest.

John Campbell, former U.S. Ambassador to Nigeria, said Wednesday that Boko Haram is able to operate “with a fair degree of impunity in perhaps a quarter or a third of the land area of Nigeria.”

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Campbell described the landscape of the Boko Haram strongholds where the girls may have been taken as “saharian” adding that it’s sparsely populated. “It’s not desert, but it’s arid,” he said on a call with reporters coordinated by the Council on Foreign Relations.

A local reporter with Nigeria’s The Nation recently wrote that while arid, the forest can bunch in places with thick thorns, making easy travel impossible.

“…[I]t also graduates from trees as low as half a meter to the extremely thick areas where human skins cannot penetrate without being hurt by thorns if you do not have a cutlass or something to ward them off,” Bodunrin Kayode wrote. “That is the nature of the forest which is being manipulated and controlled by Boko Haram, who have become masters of the savannah.”

But the problem finding the girls may be less about density and more about space, the former diplomats said. The land is so vast and so remote that it creates a needle-in-the-haystack kind of situation – a haystack in which Boko Haram knows where and how to hide.

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The amount of time passed, also, is a “huge” disadvantage, according to former FBI special agent and ABC News consultant Brad Garrett.

“If you give them three weeks to disperse, you’ve pretty much eliminated your ability to do an on-the-ground operation,” Garrett said. “What are you going to do? Go rescue three of them at a time? That puts the others in danger.”

While there’s been no official confirmation the group of girls has been spread out, Boko Haram’s leader said in an undated video released earlier this week that he already planned to “sell” the girls in the market place. American and Nigerian sources on the ground said some are believed to have been dispersed into smaller groups by Boko Haram and the U.S. State Department said Monday that the some of the girls have likely been transported outside Nigeria. Relatives of the girls have told reporters some have been spotted in neighboring Chad and Cameroon.

Garrett said any advantage now is going to come in the form of local sources of information, which can be notoriously unreliable, and which a top military official said could pose a challenge for the U.S.

“The first requirement obviously is to find them. That will require a very concerted effort, mostly of human intelligence, and that’s not a strength of the United States in this region,” Gen. Carter Ham, former commander of the U.S. military’s operations in Africa, told ABC News’ Martha Raddatz. “But the countries in the region have good human intelligence networks. They’ve got to put all effort into activating those networks and getting information.”