A cattle rancher who has spent decades exploring the nature reserve where authorities are searching for Brian Laundrie says he won’t be found there.

Laundrie has been missing since at least September 14, when his parents said he went for a hike in the Carlton Reserve in Sarasota County, Florida, and did not return. Three days before he left, Laundrie’s girlfriend Gabby Petito was reported missing by her family, who lost contact with her while she was on a cross-country road trip with Laundrie.

Petito’s body was found in Bridger-Teton National Forest on Sunday, September 19. A medical examiner has ruled the 22-year-old woman’s death a homicide, but has not yet released the specific cause of death. Laundrie was named a person of interest in Petito’s disappearance before she was found dead, and has not yet been named a suspect in her presumed murder. Last week, the FBI issued an arrest warrant for Laundrie on suspicion that he accessed another, identified person’s financial accounts in late August and early September.

Florida cattle rancher Alan McEwen has spend three decades in the area of the 25,000-acre reserve where investigators are searching for Laundrie, and told Fox News has little hope the 23-year-old man will be found there, dead or alive.

“There’s no surviving out here, I don’t know how to say it,” McEwen told the news outlet. “Unless he’s got a butt like a duck and can float, he’s not in there.”

“I’ve been in the woods in and out all my life … I have learned a lot in my life, and one thing I know is no one is gonna survive out there for two weeks on foot,” McEwen continued.

Authorities have not commented on what information they have besides Laundrie’s parents’ account that indicates Laundrie is in the reserve, though a police commander said last week he is confident investigators have not been wasting their time.

McEwen told Fox News that he has often navigated the reserve to find wayward cattle, and that he believes there would be signs of human remains if there were a body somewhere in the swampy forest.

“Anything dead you find in the woods, you’re gonna look up, you’re gonna see buzzards flying like crazy,” he said. “No buzzards, no body is my theory. And I haven’t seen any buzzards flying.”

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