HANCOCK – For the past four summers, a couple of visitors to a local marina have become more eagerly awaited than any other – and they don’t even own a boat.

They do love to fish.

And it would be hard to argue that there are many other vantage points in Maine with a more commanding position over the coastline than the top of the 90-foot crane at Hancock Marine. That is where the visitors, a pair of adult ospreys, has nested and raised a set of young every summer since 1998.

Phil Johnson, the marina owner and operator, uses the crane to put boats in and out of the water. He said the ospreys seem unaffected by his use of the crane, even though the cables that hoist the boats pass over a pulley inches from the bottom of the nest.

“They’re happy there, obviously,” Johnson said. The ospreys had a nest nearby before they spent the summer of 1998 building the one at the top of the crane, he added. He said he and his family have gotten used to having the migratory birds arrive every spring.

“We wait for them,” Johnson said. “We wonder when they are going to show up.”

Charlie Todd, a biologist with the Maine Department of Inland Fisheries and Wildlife, said ospreys have been known to build nests in cranes in Maine before. He said they usually nest in trees as eagles do but tend to be more adventurous than their larger cousins.

“That’s why people admire ospreys so much,” Todd said. “They are surprising every step of the way.”

Ospreys have built nests in a crane at a stone quarry in Tenants Harbor, in an electrical tower in East Millinocket and inside a transformer array at Mason station, a coal-burning electrical plant in Wiscasset.

“Their feathers must be standing on end all the time,” he said of the Wiscasset pair. The pair that built the nest in East Millinocket sometimes caused power outages at the nearby mill by dropping sticks from their nest onto the power lines below, he added.

Johnson said he is careful when he is beneath the boom of his crane. That’s because a man once got hit with a branch that fell from the ospreys’ nest.

“I have worried about working under it,” he said.

Johnson said the birds at his marina have twice re-built the nest after severe windstorms blew it down. He was unconcerned by Todd’s observation that osprey nests can often weigh as much as 1,000 pounds.

“A thousand pounds is nothing,” he said, adding that his crane is rated for 50 tons. The crane, which Johnson guessed was made by Lima in the 1940s or 1950s, has been used to lift boats 40 feet long, he added.

Ospreys are not rare in Maine, according to Todd. He said there are several thousand nesting pairs of ospreys in the state, both on the coast and near inland lakes and rivers. They tend to raise one to three young at a time, and can have 6-foot wingspans. The birds in Maine are most likely to spend the winter anywhere between Chesapeake Bay and Florida, but have been known to migrate as far south as Cuba, he added.

Ospreys can be spectacular fishers, virtually hovering in place over water before they plunge down for a fish, Todd said. Sometimes they dive with such force that they actually submerge themselves in the water. Birds that get their wings wet have to swim to shore and dry out their wings before they can fly again, he said.

Todd said ospreys live on average for 10 years. When they mate, they often return to the areas, if not to the actual nest, where they grew up. The chances that the nest at Hancock Marine will attract another set of birds when the current pair no longer return are good, he said.

Johnson said that the birds are expected to head south for the winter in the next few weeks.

“Whether that nest is there or not, I expect them to be back in the spring,” Johnson said.