A team of fire trackers that includes Santa Rosa fire Capt. Keith Flood headed back out into the Yosemite wilderness early Tuesday to continue mapping the path for hotshot firefighters.

Flood is part of a 12-member intelligence-gathering team helping fire officials stay on top of the Rim Fire.

The massive wildfire has burned more than 370 square miles in the Stanislaus National Forest and now is burning the edges of Yosemite National Park.

Fire mapping is a specialty job that has taken the veteran fire captain to other major fires in the state for the past several years. Before being sent to the Yosemite blaze on Aug. 17, Flood was mapping a large Butte County fire.

"It's very rewarding. Every day a new map comes out ... it has your work on it," said Flood Tuesday.

Those maps give fire officials crucial information to help them plan firefighting strategy.

While the Yosemite fire has been burning for weeks, firefighters continue to gain on the blaze. Officials Tuesday reported that more than 4,300 firefighters had gotten a line around 75 percent of the fire,up from 45 percent two days earlier.

It is the fourth largest fire in California history, having burned about 236,000 acres and 111 buildings, including 11 homes. The cause remains under investigation, although fire officials have indicated it could have started in a marijuana plot, according to news reports.

A Sonoma County strike team of five engines, and crews has been dispatched to the effort, as were other local engines and water tender trucks.

Most of those crews have returned or were on their way back home, said Sonoma County fire officials. Water tender trucks and their crews from Windsor and Glen Ellen remained at the fire.

Early Tuesday, Flood was starting his 16-hour daily shift that would include a lengthy drive, a 10-20 mile hike, weather forecasting and mapping. He was 17 days into a three week assignment.

He and another observer were headed out on Highway 120 toward the fire lines. Flood was able to talk briefly before moving out of cellphone range.

"The last two days we've been hiking out into the wilderness following hot-shot crews as they're cutting a line in the forest, using GPS to track and map it," he said.

"Today we're hiking back out to the wilderness to meet up with the hot shots in the Tuolomne River," he said.

In addition to charting the course of the fire, the crew has been mapping what is in the path of the flames or the path of the firefighters and their equipment.

"We're looking for hazards, homes, historical sites, archeological sites ..." Flood said.

The information helps firefighters know what needs to be protected or avoided. For areas that don't burn where firefighters were working, the mapping will help crews go back and restore the area as much as possible to what it was, Flood said.

Flood, 48, has been with the Santa Rose fire department for 24 years. He said he expects to head home this weekend to his wife and two teenage sons.