The active hunt for a grizzly sow and two cubs fizzled Monday, with state wildlife officials unable to locate the animals on a trail in Far North Bicentennial Park that has been the site of two maulings in recent months.

But Alaska Department of Fish and Game biologists remain determined to bring down the sow and plan to pepper the Rover's Run trail -- which remains closed following the most recent attack Friday -- with motion-activated cameras that will alert them when the bears return, said area biologist Rick Sinnott. If caught, officials plan to kill the sow and try saving the cubs.

"There's at least the potential to catch them, but, that said, our primary goal here is going to be to shoot the sow, and if we can catch the cubs after that, I think we'll try to do that," Sinnott said. "But it's not as easy as people think."

There have been five reported confrontations between brown bears and people in the park since mid-June. All but the most serious -- an attack on 15-year-old Petra Davis in late June -- likely involved the same sow, and the same bear may have been involved in that one as well, Sinnott said.

The most recent attack came Friday, when Clivia Feliz, 51, was left with a partially collapsed lung, a torn arm, and puncture marks on her head and neck after jogging up on the bears on Rover's Run.

The patrol Monday -- using biologists as shotgun-wielding bait -- spanned the trail and turned up tracks from some single bears, but no cubs. The sow and her cubs may have left the area, but they'll be back, Sinnott said. The department plans to mount as many cameras as it can borrow along the trail and creek, then check the images daily until the sow is located, even if it takes the rest of the season, he said.

Relocation is not an option for the sow because dense brush won't allow an aerial search. Darting from the ground at short range is dangerous, because the tranquilizer can take up to 10 minutes to knock a bear out, Sinnott said.

Even when they are relocated, grizzlies often try to return to their turf, said Capt. Burke Waldron, operations commander for the Alaska Wildlife Troopers, who have assisted the hunt.

"Relocating bears, brown bears in particular, historically has very low success rates," Waldron said. "Bears are very territorial and they will do whatever they can to the point of killing themselves to try returning to their home territory."

If and when the bears are spotted back along the trail system, Fish and Game will place a culvert trap to ensnare the sow, then kill it. The cubs, about 40 pounds apiece, were born earlier this year and are too young to survive on their own, Sinnott said.

Officials are looking at facilities in the Lower 48 that might need grizzly cubs so they can try saving them if they can catch the animals, Sinnott said.

"There's a very limited time frame to rescue those cubs and if we can do it safely we'll try, but if it's a three-ring circus in there, then we'll just have to put them all down," he said.