By Frank Eltman, Associated Press

New York (AP) — A humpback whale (named Jerry by some media outlets) that has cavorted in the Hudson River for nearly a week, with sightings reported from the Statue of Liberty to well north of the George Washington Bridge about 20 miles away, may be after a meal.

The U.S. Coast Guard said it has received dozens of calls reporting Hudson sightings since last Wednesday. The Hudson originates upstate in the Adirondack Mountains and flows down through the Hudson Valley, continues between New York City and Jersey City, New Jersey, and empties into the Atlantic Ocean.

Whale experts say they’ve seen increased numbers of mostly humpback whales in the New York area in recent years but it’s rare to have one travel up the Hudson.

Although most experts agree water conditions have improved in the river in the 35 years since the passage of the Clean Water Act, they weren’t willing to say that the visit from the humpback had a direct correlation.

Dennis Suszkowski, science director of the Hudson River Foundation, and Howard Rosenbaum, director of the Wildlife Conservation Society’s Ocean Giants program, said it appears the humpback may merely have been chasing after Menhaden, or bunker fish, that swam up the Hudson.

“Oftentimes in the past when we have seen these animals in and around these waters we become concerned that they are sick or injured because they are not typically found here,” Rosenbaum said. “So far with the images we have seen we don’t have reason to believe that.”

Paul Sieswerda, president of a group called Gotham Whale, said the efforts to clean the Hudson have improved conditions but added, “what those conditions are precisely is difficult to say.” He suggested that legislation that reduced fishing limits for Menhaden make them more prevalent and therefore available to the humpbacks to hunt.

Scientists have been accelerating their study of whales in the region in recent years. Last summer, the Wildlife Conservation Society, in collaboration with the New York Aquarium, teamed with the Woods Hole Oceanographic Institution in Massachusetts to deploy a high-tech buoy 22 miles off the coast of Fire Island to monitor several species of great whales.

In the past month, the buoy has detected three North Atlantic right whales, one of the world’s highly endangered whale species.

Sieswerda, a retired curator of the New England and New York aquariums, leads whale watching expeditions off the coasts of New York and New Jersey and said the number of whale sightings has soared since 2011. He said this year there have been 106 sightings, mostly of humpbacks, in an area called western New York Bight, a vast ocean region stretching from Montauk Point on eastern Long Island to Point Pleasant, New Jersey.

“I’m riding this wave,” he said. “It’s absolutely exciting.”

Jerry in the Hudson River, eying the Chrysler Building in the distance