. >> reporter: kelly landen is one of the regular spotters. originally from buffalo new york, now living in botswana. >> well the transect lines are about 15 minutes each in one direction and then on the turn we get a little bit of an eye break, we stretch, we close our eyes and try and get a regroup for a few minutes until we get to the next transect which is really quite a relief. >> reporter: in neighboring south africa the massive kruger park is also home to thousands of elephants. chase and the team won't have to do any counting here, because the south africans will provide figures from their own aerial surveys. sam ferreira is an ecologist in kruger park well aware of the difficulties of counting elephants from the air. >> imagine an elephant stands under a tree. you fly over it. the elephant is there but it's not available for you to be sampled and you can't see it. >> reporter: to compensate cameras are mounted on each side of the plane the spotters constantly take pictures. after the flight, the photos are downloaded and used to verif