An osprey clasps its freshly-caught two-foot northern pike on Lake Arrowhead last week. (Photo by Steve Costello)

The osprey sits on a log in the middle of Lake Arrowhead, a two-foot fish held tightly in its right talons, the bird unknowingly the subject of an annual pilgrimage that reached 20 years in length last week.

The bird, a stone’s throw from the cabin where Milton resident Meeri Zetterstrom started the first collaborative effort to result in the delisting of a Vermont endangered species, elicits emotions that roll over me in waves.

“Thanks, Meeri,” I say quietly as I pass the bird, leaving it to enjoy a late-day meal.

My visit to Arrowhead, which I’ve repeated each spring for two decades, has three purposes: To keep a promise I made to Zetterstrom years ago, to count the osprey nests at the manmade lake and to quietly revel in the rebirth of what in my mind is the most spectacular bird in Vermont.

Ospreys had been wiped out by DDT, a pesticide that got in the food chain and left ospreys’ eggs brittle. Not a single osprey had hatched and fledged in Vermont since the ‘40s, but Zetterstrom, a Finland native who knew the birds from her homeland, saw one lone osprey at the lake in the ‘80s.

After losing her husband and with no family nearby, Zetterstrom began a fixation on returning ospreys to Vermont, bringing electric companies and the Vermont Department of Fish and Wildlife together to work on their behalf.

“I cannot bring my husband back,” she told a reporter several years later, “but maybe I can bring back my osprey.”

Many scoffed at the idea. Some thought ospreys were gone for good, and others were put off by Zetterstrom, who they saw as a crotchety old lady, but she struck a chord immediately when we met in 1996. By then, at least two ospreys had shown up at the lake each spring for several years, but boaters often ventured too close to their nest site. Some people intentionally harassed them, and the birds failed to breed.

Zetterstom’s call turned what had been a nascent effort into a full-fledged campaign, as she, Steve Parren from Fish and Wildlife and I collaborated on media outreach, education in the local schools and buffer zones to protect what she referred to as “the honeymooners.” At times, it felt like a full-time job.

Two years later, the first osprey in more than 60 years hatched in Vermont.

Zetterstrom said she cried.

When I heard the news, I did, too.

More chicks hatched the next year, and more the next. Soon, five pairs were nesting at Lake Arrowhead, with others up and down Lake Champlain.

Zetterstrom spent countless hours photographing ospreys and watching through binoculars as one or two flew past her home, landed on a dead pine tree nearby or fished the waters below. When she began to lose her eyesight soon after that first bird hatched, my pilgrimage was born.

Handing me a canvas bag filled with a camera, lenses and assorted equipment, she asked for a simple favor: “Come up and take pictures of the ospreys each year.”

Zetterstrom died in 2010, but lived to see the state officially remove ospreys from the endangered species list. I continue to visit the lake and the birds each year, often between April 5 and 12, when Zetterstrom’s meticulous records show they almost always return from their wintering grounds down south. I still use her old-school film camera and lenses to photograph them, along with newer digital equipment.

Each visit is a gift, and each brings up the same emotions: gratitude, joy and a touch of sadness.

Sadness that Zetterstrom isn’t alive to see nearly a dozen ospreys flitting across the waters just below her home, collecting sticks and small branches to build their nests.

Joy brought on by the thrill of watching ospreys tuck their six-foot wingspans alongside their bodies as they plunge face first toward the water for their next meal.

And gratitude to Zetterstrom for her foresight, her vision and for passing on to me a love of wildlife photography and a bird I barely knew existed until I met her.

Steve Costello is a vice president at Green Mountain Power and lives in Rutland Town.