Adlar Stelly is 42 years old, which means it is fair to say that he has been involved in farming crawfish in Louisiana for just shy of 42 years.

He grew up surrounded by the shallow ponds dotted with the netted crawfish traps set by his father. At 7, he was steering the boat while his older brother pulled in the traps. Before long, he graduated to emptying them himself. He and his brother now have some 3,000 acres of ponds of their own in southern Louisiana.

He has seen abundant seasons and others that were more sparse. But over all that time, he has never experienced a season as distressing as this one, where, week after frustrating week, the traps have been so consistently bare.

The haul at one pond on a recent day was enough to fill four sacks, each roughly the size of a large pillowcase. In a better year, that haul would have been 25, maybe even 30 sacks.

“Here we are, we’re halfway through Lent,” Mr. Stelly said, pointing out what is usually the peak time for boiling live crawfish in this heavily Catholic part of the world.

“You’re running out of time,” he added. “The stress is at an all-time high.”

The persistent heat that roasted the Gulf Coast during a record-setting summer is still punishing Louisiana. Farmers and scientists say the summertime drought has delivered a blow directly to the state’s soul in a way that hurricanes or other extreme weather never have: It has come perilously close to ruining crawfish season.