BOISE, Idaho (AP) — Shane Del Grosso spent some 30 summers crossing smoke-shrouded mountains and forests to fight increasingly devastating wildfires in the U.S. West.

Toward the end, his skills and experience propelled him to lead a federal multi-agency team that responded to large-scale national disasters. On some days he directed a thousand firefighters and helped coordinate aircraft attacks on massive blazes.

But then came the long offseason lacking the shared-risk camaraderie. Isolation closed in, his family said, along with marital problems that can be exacerbated by first-responder jobs that require missed family events and birthdays.

Del Grosso, 50, killed himself May 9, 2016, not long before the start of another wildfire season.

“I always thought that you’d see it coming, but I guess you don’t,” said his best friend, Noel Matson, who worked and fought wildfires out of the same U.S. Fish and Wildlife Service office in Huron, South Dakota, as Del Grosso. “It was maybe that male bravado firefighter thing where you don’t talk about what’s bothering you.”

Federal officials at the National Interagency Fire Center in Boise have started making efforts to change that mindset after noticing an increase in wildland firefighter suicides in recent years.

“It’s not a profession where people want to reach out for help because they are the help,” said Jessica Gardetto, a fire center spokeswoman and former wildland firefighter. “The federal agencies have realized, whether it’s suicidal tendencies or just overall mental health, it’s a resource that needs to be available — even out on the fire lines.”

No figures on wildland firefighter suicides are available because federal agencies often track only fatalities that occur during work hours, and families don’t always release a cause of death.

But Gardetto said the wildland firefighting community is small, “and word spreads quickly.” Anecdotal reports suggest many of the suicides are happening outside the wildfire season. A month ago, she said, a U.S. Forest Service firefighter based in the U.S. Southwest killed himself. And she said several suicides occurred in Idaho in 2017. One of those was a Boise-based U.S. Bureau of Land Management smokejumper, a firefighter who jumps from airplanes.

Reasons for the rise are unclear, though some cite longer and tougher wildfire seasons and an increase in the number of wildland firefighters who previously served in the military and were already dealing with post-traumatic stress.