Erik Cowie's cause and manner of death have been revealed.
The zookeeper, who was famous for appearing in "Tiger King," died at the age of 53 in September.
The New York City Office of Chief Medical Examiner confirmed to Fox News on Monday that Cowie's manner of death was natural and that the cause was "acute and chronic alcohol use."
Cowie entered the public sphere in 2020 with the release of Netflix's "Tiger King: Murder, Mayhem and Madness," a docuseries that followed Cowie's boss, Joseph Maldonado-Passage, and his zoo full of exotic animals.
'TIGER KING' ZOOKEEPER ERIK COWIE DEAD AT 53
In the series, Cowie said he found the job on Craiglist and was desperate for work.
According to TMZ, Cowie died on Sept. 3. He was found dead in New York City.
At the time, cops confirmed to Fox News that they responded to an emergency call of "an unconscious male inside of 21 East 55 Street in the confines of the 67 Pct."
The man was in the bedroom of the location. "EMS was on scene and pronounced the male deceased. The Medical Examiner will determine the cause of death," the authorities said.
There were no drugs reportedly found at the scene.
'TIGER KING' STAR JOE EXOTIC'S PRISON SENTENCED VACATED, COURT ORDERS RESENTENCING
Cowie was one of the animal caretakers at the Greater Wynnewood Exotic Animal Park and testified against Maldonado-Passage – better known as Joe Exotic – who is currently serving 22 years in a Texas prison after being found guilty of hiring two hitmen in a failed murder-for-hire against his big cat zoo rival, Carole Baskin.
Cowie also said in court he witnessed Exotic's alleged mistreatment of the animals and confirmed Exotic killed some of the older big cats to make room for new ones.
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Per TMZ, Cowie was arrested for DUI after a car accident in Oklahoma in May. He pleaded guilty and was supposed to show up in court for sentencing but never did.
After "Tiger King" went viral, Cowie also got a new set of teeth.
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Fox News' Jessica Napoli contributed to this report