Bear watchers eager to get a last glimpse of Grand Teton’s most famous grizzly family likely have only weeks before the cubs set out to fend for themselves.

Grizzly bear No. 399 and her three cubs recently emerged from their den and are, once again, providing park visitors with spectacular viewing opportunities and photographs around Jackson Lake Lodge and Oxbow Bend.

This is the third spring No. 399 and her cubs have fed and played just off the roads near Jackson Lake. Park officials say this could be the last spring No. 399 and her cubs stay together.

On Sunday, people noticed No. 399 for the first time this spring, and the popular grizzly family has since caused several bear jams along the park roads, Grand Teton spokeswoman Carol Cunningham said.

Other bears have begun to emerge from their dens in the park as well, and it’s time for people to carry bear spray and observe food-storage regulations, Cunningham warned. Yellowstone National Park and Wyoming Game and Fish Department officials started reporting bear sightings in late March.

Mother bears, like No. 399, usually allow their cubs to stay with them for just more than two years, and she’ll likely encourage her offspring to leave sometime between May and July, Grand Teton senior biologist Steve Cain said. Rarely, mother bears allow their cubs to den with them for a third full winter.

Once on their own, female cubs usually stay close to their mother’s home range, while the males tend to disperse farther away. Of the three cubs, at least one is a male. The sex of the other two is unknown.

Park officials might attempt to capture No. 399 and her cubs for research purposes sometime this summer. Cain said the mother and her cubs appear to be in excellent shape.

After the cubs are gone, 12-year-old No. 399 could then “regain her breeding status” in time to mate before next denning season. Cain said female bears can successfully raise young into their 20s.

The problem with No. 399’s cubs is that they have become accustomed to roads and developed areas, which could mean problems later on, Cain said.

“The fact that they are habituated somewhat predisposes them to food conditioning because they are more likely to approach developed areas where [human] food might be more accessible,” he said.

Food-storage regulations in the park have helped keep No. 399’s family out of trouble so far, but one or more of the cubs could disperse to a location where human food is easier to attain, Cain said. Once a bear has received a food reward, officials say it often results in a death sentence for the animal because they almost always become increasingly aggressive at seeking out other sources of human sustenance.

Though park officials consider No. 399 and her cubs habituated to human presence, the grizzly bear family has not yet received any human food rewards and have caused few problems.

Last year, a man hiking near Jackson Lake Lodge surprised No. 399 as she and her offspring were feeding on an elk carcass. He sustained several puncture wounds, but his injuries were considered minor. Park biologists determined that No. 399 displayed normal bear behavior by defending her young and the carcass, and officials decided to allow her and her family continue to roam freely.

Grand Teton officials will close the Willow Flats area near Jackson Lake Lodge from May 15 to July 15 to prevent human-bear encounters.

According to Cain, park officials will step up efforts to keep bears and people safe at bear jams and campgrounds this year with a six to eight person “wildlife brigade.”

The brigade, which is a mixture of volunteers and staff, will help reinforce food storage regulations and provide education in areas where human-bear conflicts are likely to occur, he said.

Cunningham said that park officials recommend that people stay at least 100 yards away from wildlife, especially bears.

“Even though [bears] appear calm, behavior can change pretty quickly,” said Cunningham. “Have the pepper spray accessible. Have it someplace where you can get to it pretty quickly.”

“I was biking on Sunday and saw tracks along the Teton Park Road near Burned Bridge,” Cunningham continued, explaining that black and grizzly bears are common in Grand Teton. “It seems like all of the sudden the bears are coming out.”