“Hello, this is a message for Barb Kloehn. I’m calling from the Allens Pond Wildlife Sanctuary of Dartmouth, where presumably you visited not too long ago. We have very good news for you.”

That was part of the message Gina Purtell, director of Allen’s Pond Wildlife Sanctuary, left for the winner of the 12th annual Duck Derby. On Saturday night, 5,479 rubber ducks were unleashed in the waters of Allens Pond. On Sunday, just over 40 of the top finishers were awarded various prizes during an outdoor festival in Westport.

The coveted top prize: dinner for two anywhere in the world. That includes the cost of airfare and two night’s stay at a hotel.

After announcing the winner on Sunday afternoon, Purtell attempted to reach out to the winner, Barb Kloehn, only to get her voicemail.

“We’re all desperately waiting to hear what you think of this and where you’re going to go,” said Purtell in the message.

Jen Costa, who manages the derby, described the winner as a “mystery woman.”

“She bought it in person — we just don’t know where,” said Costa. “Maybe at the farmers market, at Padanaram, the Bayside [Restaurant]…but she filled out her name, her number and an email address.”

She said the number Kloehn listed in the entry form had a Colorado area code. While the group awaits word from the winner, the event organizers were pleased with this year’s turnout.

“The Duck Derby is one of our most important revenue streams. It produces about 20 to 25 percent of our annual operating budget,” said Purtell.

The event started 12 years ago when Norm Buck and Malcolm Johnston pitched the idea to the sanctuary. The first year, they sold more than 3,000 ducks and raised about $20,000.

“The prize is what sells it,” said Buck. “People have gone everywhere in the world. People have gone to every continent, expect North America.”

“There’s duck races all over the place,” added Johnston. “They don’t have that first prize.”

Johnston said the grand prize is funded through the event’s major sponsors, so when people buy ducks for the race, the proceeds go to toward the sanctuary.

“One of the things I think is interesting about the duck race is, at $10 a pop, it’s at a level that just about anyone can participate,” said Purtell. “Unlike some gala events, this may not gross as much, but it does allow anybody to participate.”

During the race on Saturday night, five volunteers collected thousands of rubber ducks in a large net and unleashed them about 400 feet away from the finish line. The race happens at high tide, ensuring a strong current to carry the fleet along the waters of Allens Pond.

From shore, the yellow racers looked like specks of pollen being carried along the surface of the water. Kloehn’s prize-winning duck, named Si-Cash, scurried to the finish line in about four minutes.

Purtell, who was recording the race on her phone and giving a play-by-play of the action, said the race helps with the conservation of local birds and the ecosystem.

“The sanctuary’s goal is to foster conservation of Allens Pond and its surrounding habitats and manage it. We have some rare or special ecological resources here,” she said.

This includes monitoring the populations of the piping plover, the bobolink and terrapin turtles. Purtell said the birds, in particular, had a successful nesting season this year. She said that in Allens Pond alone, there were 18 pairs of piping plovers nesting by the water. In the grasslands of the sanctuary, the group identified 10 pairs of bobolinks.

The duck race helps the sanctuary maintain the land and run an extensive internship program, where participants learn about animal tracking and ecological management.

“It’s a huge success. We’ve done all the bird work. The birds have fledged. At this point we’re glad to celebrate. It’s a great time of year,” said Purtell.