Jason Musgrove has spent every day for the past two weeks trying to find out whether his mother is alive or dead.

He and his stepfather drive to shelters, clinics and aid distribution sites around Maui, lurching between hope and despair, like hundreds of other families still searching for relatives and friends in the wake of the fires that destroyed the coastal town of Lahaina. Mr. Musgrove asks: Has his mother, Linda Vaikeli, 69, ended up as a Jane Doe in a burn unit? Is she too traumatized to call her family? Why does he still not have an answer?

The fire’s official death toll of 115 marks the worst wildfire in more than a century, but that figure has overshadowed a potentially more ominous statistic: Roughly 1,000 to 1,100 others are still listed as unaccounted for, according to the F.B.I.

They include immigrant hotel workers who spoke little English, multigenerational families who were living in close quarters when the fire swept through their homes, residents of homeless encampments, and grandparents who had trouble walking and did not use cellphones.

Two days after the fires, the authorities on Maui began registering the names of the missing and taking DNA from family members to help identify remains. But families said they have received almost no updates and have had to rely on crowdsourced lists for basic information about who was missing, or how many people were still lost amid the rubble.

Hawaii’s governor has warned that the death toll would rise substantially. But the number of confirmed deaths has barely changed for several days, even as search teams say they had finished combing through 87 percent of Lahaina’s ash and rubble. This uneven progress has created a desperate disconnect between official announcements and family members’ gnawing fears.

“The numbers are not adding up,” Mr. Musgrove said.

Some families have held out hope that the people listed as missing are still alive and have been unable to check in after losing their cellphones. But relatives have started to ponder horrible uncertainties, even as they circle the island and hand out missing posters.

They wonder: Could their loved ones have been so obliterated by the fire that they will never be found? Could they have been swept out to sea after jumping into the Pacific to escape the smoke and flames? Are searching families foolish to still hold onto hope?

“I’m going to keep searching,” Mr. Musgrove said Monday afternoon, after another fruitless hunt. “I only have one opportunity to do this. To find my Mom.”

It can take months or even years of painstaking forensic analysis and DNA testing to identify the dead, as seen after the mass losses of life during the Sept. 11 attacks, Hurricane Katrina and infernos like the one that consumed Paradise, Calif.

“We may not know in the end about everybody,” Steven Merrill, the special agent in charge of the FBI’s Honolulu field office, said at a news conference on Tuesday.

A few days after the fire that destroyed Lahaina, anthropologists from California State University, Chico, arrived on Maui to work with search-and-rescue teams to help identify fragments of bone in the rubble. The process is a painstaking one with which anthropologists are familiar from archaeological digs.

By the time they arrived, any bodies that were intact or even partly recognizable had already been found and placed in a mobile morgue near the Lahaina Civic Center, according to Dr. Eric Bartelink, an anthropologist at Chico State. The remains included charred bodies found in cars on Front Street as well as many bodies recovered from the ocean, he said.

Dr. Ashley Kendell, who was also part of the team from Chico State, said the conditions of the remains discovered in Lahaina were similar to what she found while working in the aftermath of the 2018 Camp fire in Northern California.

“In wildfire contexts or really any fire scene, everything is grayscale. Everything looks very, very similar,” she said. “And it really takes a very trained eye to recognize burned bone. So having us on scene helps make those IDs possible. We are very good at locating remains within a debris pile without having to do any excavation or further damage.”

Ultimately, 84 of the 85 victims of the Camp fire were identified after several months. Dr. Kendell said she was hopeful for a similar result in Lahaina, but the process will take at least several months.

This week Tim Laborte was driving around West Maui with a pile of missing posters, looking for his stepfather and his dog, Haupia, named after a traditional Hawaiian coconut dessert. Mr. Laborte said that his hope, however faint, was being kept alive after a possible sighting of his stepfather.

“We had heard that someone saw him, but we took it with a grain of salt because there are a lot of Filipino guys with dogs,” Mr. Laborte said.

Mr. Laborte has been leaning on a sense of equanimity nurtured by his Buddhist faith. “Your time is going to come,” he said. “It’s just a matter of when. It’s inevitable, so it’s nothing really to cling to or worry about. If he’s passed, it’s OK. But if he’s alive, we have to keep looking.”

Dana Condrey decided to fly to Maui after 10 days without word from her 56-year-old brother, Phillip Hudelson, a bartender at Cheeseburger in Paradise, a restaurant that was destroyed in the fire. Ms. Condrey suspected that her brother would have avoided crowded rescue shelters, so she started driving around to parks, grocery stores and hotels, trying to imagine where he would go. On Monday, she got a phone call from a Red Cross worker who had taken her DNA sample: Mr. Hudelson had been found.

After escaping the fire on his motor scooter, he spent a week sleeping on the beach and eating canned soups that he had warmed in the sand. He then checked into a hotel that was providing shelter in Kaanapali to evacuees. He was sunburned and in shock, still wearing the same clothes from the fire. But alive.

“We just started crying and embracing,” Ms. Condrey said. “It’s an absolute miracle.”

Such stories proved to Mr. Musgrove that there was still some hope, however slim. His mother, who some days could barely lift herself out of bed, had been home alone in her apartment the day of the fires, and she did not call or text her husband or other relatives, as far as they knew.

But when Mr. Musgrove began sifting through her iCloud data, he found four blurry photos taken at 2:04 p.m. that day. Were the photos another dead end or some sign that she had tried to escape?

“The pictures gave me hope,” he said, but it was a wary one. “Am I so desperate that I’m creating this? The smallest things — you grasp onto.”

He puzzles over the pictures now, playing with their contrast and hue to search for some clues. In quieter moments, he and his stepfather share memories of Ms. Vaikeli’s passion for cake-baking, and listen to old voice mail messages in which Ms. Vaikeli sings Happy Birthday in her Texas twang.

Then they plot where to look next.

Sheelagh McNeill contributed research.