Beavers grace New York City's official seal. But the industrious rodents have not been seen in the flesh here for as many as 200 years — until this week.

Biologists videotaped a beaver swimming up the Bronx River on Wednesday. Its twig-and-mud lodge had been spotted earlier on the river bank, but the tape confirmed the presence of the animal itself.

"It had to happen because beaver populations are expanding, and their habitats are shrinking," said Dietland Muller-Schwarze, a beaver expert at the State University of New York College of Environmental Science and Forestry in Syracuse. "We're probably going to see more of them in the future."

Beavers gnawed out a prominent place in the city's early days as a European settlement, attracting fur traders to a nascent Manhattan. The animal appears in the city seal to symbolize a Dutch trading company that factored in the city's colonial beginnings, according to the city's Web site.

But amid heavy trapping, beavers disappeared from the city in the early 1800s, according to the city Parks & Recreation Department.

The beaver that has made its way to the Bronx appears to be a male, several feet long and two or three years old, said Patrick Thomas, the mammals curator at the nearby Bronx Zoo.

Biologists have nicknamed the animal "Jose," as a tribute to U.S. Rep. Jose Serrano's work to revive the river. The Bronx Democrat lined up federal money for a cleanup.

"But I don't know to what extent I imagined things living in it again," he said.