"The lost was found," said Ken Balcomb, veteran orca researcher at the Friday Harbor center. "It wasn't with its mom that day," he added of reports last week that the calf was missing and perhaps dead.

The state's three resident orca pods- dubbed J, K and L - were declared an endangered species last year, and disappearance of the newborn that had boosted the population to 90 for the first time this century was painful news.

The calf - whose orange newborn coat made it stand out among its black-and-white family - was first spotted Aug. 13 in Haro Strait, on the west side of the San Juans, where the orcas congregate over the summer to chase salmon.

But then it was not seen for days.

"J, K and L pods have been pretty much together this (past) week when they've been seen," Balcomb said. "He didn't show up with any other pod."

There were a couple possible sightings, but no documentation until Sunday.

"We have to go by a picture to be sure," he noted.

"He's an adventurous little guy," an exuberant Balcomb said. "But he was there today, nice and tight" with the other orcas.

"He's moving around," the researcher added. "He'll surface way ahead of Mom. Very unusual for that small of a baby."

He said K-41 was likely born shortly before the Aug. 13 sighting, making it "probably just a little over a week old."

It was clear Aug. 13 that the calf belonged to K-22, a 19-year-old female named Sekiu, said Kelley Balcomb-Bartok of the research center. They were swimming with Sekiu's first calf, 5-year-old K-33, or Tika, while the rest of the pod was a few miles ahead.

Orcas are about 8 feet long when born and weigh about 400 pounds. They know how to swim at birth and are nourished with milk from their mother. The white parts of the black-and-white orcas are flushed orange at birth, and observers often see "fetal folds" before the skin stretches tight.

The newborn, designated K-41, would have kept that number even if it was never seen again, Balcomb-Bartok said.

The "southern resident" orca population, which frequents Puget Sound and nearby waters, is believed to have numbered 140 or more in the last century. It has suffered several major periods of decline since the 1960s, when the whales were caught for aquariums.

The population rebounded to 97 in the 1990s, then declined to 79 in 2001.

The federal government listed the southern resident orcas as an endangered species in November 2005, giving them the highest level of protection available under the law. The designation targets pollution, increased vessel traffic, prey decline and other factors that have contributed to the faltering numbers.

A similar inland population, called the northern residents, summers between Canada's Vancouver Island and the mainland. Both feed primarily on fish, though many other orca populations eat seals, young whales and other marine mammals.

Orcas, actually a kind of dolphin, are found in all the world's oceans.