Helis, the beluga whale, in the upper Delaware River near Burlington, New Jersey, weekend of April 16th, 2005 (Photo: NOAA)

KRUEGER: (laughs) This is adding to the confusion for the weekend, and you know, it's an interesting point for people who haven't seen whales before and it's creating a lot of additional boating traffic and a lot of interest on the Delaware.

[BOAT MOTOR SOUNDS]

KING: New Jersey State Police Marine Trooper Kenneth Minnes says he's gotten used to seeing Helis while out on patrol.

MINNES: He likes to hug either the Pennsylvania Channel or the New Jersey Channel, depending on which direction he heads. He doesn't allow us to get too close to him. All you basically see is him surfacing and then he dives again.

[SOUND OF ROWING, PADDLES SPLASHING]

KING: Bill Lance and Kim Seba came in their boat from Mount Laurel, New Jersey, hoping they'll be lucky.

LANCE: We're out to see whether we can get a picture. We've got our cameras, everything else, ready to go, we've got our lunch. We're gonna stay out here all day until we see it! (Seba laughs).

[BOAT MOTOR SOUNDS]

KING: Also on the river is Jamison Smith, a marine biologist here from the National Marine Fisheries Service in Gloucester, Massachusetts. He says the whale was originally spotted in Canada's Gulf of St. Lawrence in 1986. Wildlife officials there gave him the name "Helis," from the French word for propeller, after the propeller-shaped scar on his back.

SMITH: It's estimated that this animal is a minimum of 25-plus years old, which is getting up in age for a beluga. The life span, we think, is 40 or so years. So this is an adult animal.

KING: Smith says there are several theories about what might have prompted a beluga whale to travel from Canada to New Jersey.

SMITH: Getting older in age, he may not be maintaining his status in the pod that he once did and one theory is that he kind of got left behind from the pod or the group of animals and this is where he ended up. It's my observation here that he has no problem swimming against a very strong current, maintaining very good speeds, both against and with current. And, by no means has he been inactive here. He tends to pretty much pop up anywhere and everywhere around here.

[BIRD CALLS, RIVER WILDLIFE]

KING: Fly fishers call the upper Delaware the best wild trout stream east of the Rockies. It's the longest free-flowing river east of the Mississippi, running 375 miles from the great Jersey Skylands to the river's mouth at Cape May Point. In spring, shad make their annual run up the river to spawn and that could be another reason why Helis made the trip.

[CASH REGISTER SOUND]

KING: And while Helis's enjoyed the local river catch, his visit's also brought a rare influx of tourists to tiny Burlington, New Jersey. At "Ummm" ice cream parlor on High Street, a line of customers flows out of the door and onto the street. Owner Matt Garwood hardly has a moment to talk as he scoops and rings up ice cream cones.

GARWOOD: It's keeping us busy. Sellin' it this way and makin' it in the back at the same time. Right now we have "beluga" ice cream, which is basically a rename of our vanilla ice cream for the whale.

[PEOPLE BUYING IN BAKERY]

KING: Down the street at JB Bakery, Steven Simon and his brother Paul fashioned a whale-shaped cookie cutter and say they've sold hundreds of the two dollar whale cookies since Helis's arrival.

SIMON: The minute that we put it out it just started flyin' off the shelves. Everybody was really excited to have one. We've sold over 2,500 cookies. Probably by the end of the day it might be close to 3,500.

KING: The cookies are a big hit out on the Burlington river promenade where tourists and residents have flocked to catch a glimpse of Helis, the white beluga whale.

[RIVER PROMENADE SOUNDS]

KING: But marine biologist Jamison Smith says the best thing to do is leave Helis alone to enjoy his time on the Delaware.

SMITH: We're taking a standoffish approach that if you see it, let us know where it is, let us know how it's behaving, but just give it its space. And, when it feels it needs to leave, it'll go on its own accord.

KING: And, apparently, that's just what Helis has done. A tugboat reported seeing Helis headed toward the Delaware Bay, about 40 miles from the Atlantic. And the National Fisheries Service believes Helis has made it safely back to the ocean.

That's not stopping some people from coming to Burlington's river promenade, and the scenic overlook on Route 295, still hoping to catch a glimpse of the white beluga whale. They're keeping close watch over the stretch of river where the whale was seen swimming back and forth for days and wondering if Helis might change his mind and come back this way yet again.

[RIVERBANK SOUND]

KING: For Living on Earth, I'm Carole King in Burlington, New Jersey.

[MUSIC: Teisco Del Ray "Hermanos Alou" Plays Music for Lovers (Upstart Sounds) 1996]

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[MUSIC: "Iris" Miles Davis: E.S.P. (Sony) 1991]