(CBS News) It's that time of the year when the call of the wild rings out loud and clear, in backyards and fields across America. Serena Altschul has been listening, and she reports our Cover Story:
Every May there is excitement in the air at the Magee Marsh boardwalk near Toledo, Ohio. Migratory songbirds have arrived from their long trip from South and Central America, and they pause on the shore of Lake Erie to gather their strength before continuing across the big water.
For Kim Kaufman, one of the organizers of what's billed as "the Biggest Week in American Birding," it's a magical time.
"Essentially what we're doing is connecting world travelers, birds and people, in this amazing place in northwest Ohio," Kaufman told Altschul.
Each year crowds of birders flock to ooh and aah over the warblers and finches and other tiny beautiful songbirds.
"You never know what you're gonna find out there," said Kaufman. "It's like a treasure hunt in some ways."
And the treasure is becoming ever more rare.
Figures show the populations of many of our most common birds are in steep decline -- down dramatically in the past 4 decades.
But still, "birders" as they're called keep coming - about 47 million of them, according to the U.S. Fish and Wildlife Service.
Impressive numbers for sure, but a new birding craze? British photographer Richard Crossley has his doubts. He doesn't see birding as being very popular in the U.S. "No, not compared to Britain or Europe or even other countries in the world. But it should be. That's the thing, it should be ten times bigger than what it is.
"I often tell people the only difference between America and Britain is, over here, there's five times as many birds, they come twice as close, they're everywhere, and the weather's always sunny. Apart from that it's just the same!"
Over in Indiana, the songbirds' seasonal migration is celebrated, too -- only a smaller scale.
At the Indiana Audubon Society's Mary Gray Bird Sanctuary, there's a competition for young people to see how many types of birds they can find in a single day. For 13-year-old Alexandra Forsythe, it's also a chance to try to get some good pictures.
And how many different species did Forsythe find? "Exactly 60 of them!"
And she has the pictures to prove it. Along with the purple finch, her snaps include an indigo bunting, a Kentucky warbler, and a ruby-throated hummingbird.
WEB EXCLUSIVE VIDEO: At the Mary Gray Bird Sanctuary Altschul held an exhausted hummingbird in her hand until it came to life, as recorded by Alexandra Forsythe.}
But as beautiful as they are, when she's out in the woods, it's the sounds that charm her.
"Even though you can't see them, you can just hear how beautiful they are," she told Altschul. "Sometimes even the dullest birds have the prettiest voices."
There's possibility behind each leaf.
Bird enthusiasts Major Randel Rogers and his fiancee, Doreen Whitley, discovered their first oven bird. The two met while birdwatching, and found they shared this mutual passion. They will soon be married.
"We flock together!" laughed Rogers.
Rogers brought his birdwatching zeal with him when he was posted to Iraq. "The diversity of wildlife in Iraq and the birdlife is amazing," he said. "I found eventually 127 species of birds just on Al Asad Airbase, where I was stationed."
In another part of Indiana, author Brian Kimberling found inspiration for his first novel, "Snapper," deep in the Yellowwood State Forest.