Volunteering for the Society for the Protection of Nature in Israel's annual survey of migrating birds in Israel's skies is not for the novice bird-watcher. First, the watcher has to spot the flecks hundreds of meters up in the air, then identify them and then estimate their numbers - all while the birds are flying overhead at around 50 km per hour. For experienced bird-watchers, like Nico Noondhof and Erwin Booij - who flew here from the Netherlands especially to volunteer for the survey - it is a chance to see flocks of eagles and pelicans that simply do not grace the skies of any other country in such numbers. "It's amazing," Noondhof told The Jerusalem Post on Tuesday, in a field near Nahalal in the Jezreel Valley. Outfitted with his own equipment - telescope, binoculars and camping chair - Noondhof has been counting birds of prey and pelicans for hours on end daily. Noondhof has traveled widely to watch birds, throughout Europe and Asia and the Middle East, "but it cannot compare to Israel during the migrating season." In the few hours during which the Post joined the survey line, 700-800 eagles flew by and about 2,200 pelicans winged their way south in one giant flock. The annual survey, which has been taken every year since the early 1980s, is financially supported by the Israel Air Force. Several decades ago, after they stopped training over the Sinai, the air force began losing a number of pilots and planes because of mid-air collisions between feathered and metal flyers. When a supersonic jet and an eagle collide, it's apparently not a pretty sight for plane or bird. So the IAF joined with Tel Aviv University professor and International Center for the Study of Bird Migration Director Dr. Yossi Leshem to map the skies. While another ornithologist, Ehud Dovrat, began noticing the migration in the late 70s and launched the survey, the air force quickly realized its value as well. On Tuesday, survey project coordinator Jonathan Meyrav was constantly on the phone to his contact in the air force, warning him of impending flocks. The birds are tracked from the Hula Valley in the North down through the Jezreel Valley. The air force plans its take-offs and landings from the nearby base as best it can in light of Meyrav's reports. At one point, the planes didn't take off at all as the pelicans flew by. At another, they took off the other way to avoid the birds. And at still another point, they took off into the birds' flight paths but then banked sharply away, to train in another area of sky. Israel is in a unique position to observe bird migrations, as it is a way station between Europe and Asia and Africa. Over 500,000 birds traverse its length each season. It is the only place in the world to see so many birds of prey, like the greater spotted eagle, the lesser spotted eagle, the kite and others, as well as pelicans flying over, Dan Alon, who coordinates all of SPNI's birding centers explained. Alon has been a bird-watcher since the early 1980s when he was just a teenager. He was the first IDF bird-watcher, a position he believed no longer existed, he said Tuesday. He was somewhat at a loss to describe why bird-watching appealed to him, despite his obvious fascination. "Just look at them," he gestured toward the sky, with a gleam in his eye. Noondhof was better able to describe what appeals to him about the solitary hobby. When he is not watching birds, Noondhof makes cheese, among other things. "You're living in nature, spending the whole day outside, every season is different. You never know what nature will bring you and that's exciting. And you can do it everywhere in the world, because birds have no borders," he told the Post. He's been to Israel seven or eight times, sometimes down near Eilat to watch the birds there as they wing their way to Africa. This was Booij's first time volunteering for the survey and he seemed a bit overwhelmed by the sheer number of avians. "We get up at about a quarter to six and stay until three in the afternoon. It's a tough job but someone has to do it. There's a similar mass migration in Holland but not as many birds of prey. To see 20,000-30,000 fly by is quite something," he said. Booij was not to be distracted by visiting journalists or requests to report in - when he was counting, nothing else mattered. With a survey going back almost 30 years, the bird-watchers have noticed some changes in migrating populations. "Between 1982 to 1986, there were about 100,000 buzzards flying over every year. In 1987, that number dropped to 70,000 and for many years it fluctuated between 50,000 and 70,000. It is only in the last five years that we've seen 100,000 flying by again," Alon said. What caused the drastic reduction in population? "We now believe that the buzzards' nesting area was around Chernobyl. We think they took a hard hit after the nuclear reactor accident and it took them many years to come back to full strength," Alon said. Worldwide, bird-watching is hugely popular, Alon said. The two biggest organizations boast one million members each. In Israel, it's a much smaller phenomenon. The SPNI has 12 watchers, and can call on another 15 or so for special projects. There are about 200 volunteers in Israel and another 1,500 or so who express interest or join bird-watching outings on occasion, according to Alon. For all the fascination with them on the ground, the birds overhead were regally oblivious to it all, winging their way south, doing what comes naturally.