Authorities Have Yet to Rule Out at Least Two Possible Causes of Death for Family Found Dead Near Yosemite

Police are chipping away at the mystery of what led to the demise of a California family and their dog

UPDATE: OCTOBER 1 — Authorities have yet to determine what caused the death of a family and their dog during a hiking excursion in the Sierra National Forest in mid-August, but this week they announced they’ve ruled out several more potential causes.

Back on August 27, the Mariposa County Sheriff’s Department announced that weapons and chemical hazards had been ruled out as having caused the demise of Jonathan Gerrish, 45, Ellen Chung, 30, their 1-year-old daughter, Aurelia Miju Chung-Gerrish, and their dog, Oski, whose bodies were found near Hite’s Cove in the Sierra National Forest on August 17. This week, they added several more to the list: lightning strikes, carbon monoxide or dioxide poisoning, exposure to cyanide, illegal drug, or alcohol consumption and suicide.

As the SF Gate points out, one potential cause of death hasn’t been ruled out: a toxic algae bloom. As they report, “Testing conducted earlier this month confirmed that the nearby Merced River had high levels of toxic algae,” but experts have said that sort of poisoning would be difficult to pin down. Authorities also haven’t ruled out extreme heat.

“We respect and understand the need for information and details regarding this case. Our current priorities remain supporting and informing the Gerrish / Chung family during this tragic time,” Mariposa County Sheriff Jeremy Briese said in a statement published by SF Gate. “As we navigate through this investigation with the family, we will later share our findings with the public.”

AUGUST 27, 2021 — Ten days after the bodies of Jonathan Gerrish, 45, Ellen Chung, 30, their 1-year-old daughter, Aurelia Miju Chung-Gerrish, and their dog, Oski, were found near Hite’s Cove in the Sierra National Forest on August 17, investigators still don’t know how they died, but on Thursday the Mariposa County Sheriff’s Office released what new details they have uncovered.

As the Sacramento Bee reports, the Sheriff’s Office says it has “ruled out” weapons or “chemical hazards” along the Savage-Lundy Trail where the family was discovered as possible causes of death, but emphasized that, “ALL other potential causes of death remain.”

Although preliminary autopsy results revealed no clues, Sheriff’s spokeswoman Kristie Mitchell said Thursday, “The pathologist currently is issuing an autopsy finding of ‘pending toxicology.’”

The police have not said what toxins they are looking for, and the toxicology tests have not been completed. Samples from a necropsy performed on Oski, an eight-year-old Aussie-Akita mix, have been sent to several labs as well.

Water samples from the Merced River near where the Chung-Gerrish family were found were sent to labs for testing on August 19 because there was a known toxic algae bloom in the area. Additional water samples from “along the trail” nearby were collected on Monday. The water the family carried with them is also being tested.

The samples have been sent to the California State Water Resources Board along with independent labs for testing, and Mitchell said the department is getting “further assistance for additional testing” from the Centers for Disease Control and Prevention and the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment.

Additionally, the sheriff’s office said that the 2018 Ferguson Fire had turned five miles of the 8.5-mile Savage-Lundy Trail loop into a “steep southern exposure path with little-to-no trees or shade.” Temperatures in the area between 11:50 a.m. and 5:50 p.m. on August 15, when the family is believed to have been hiking there, ranged from 103 to 109, according to the Sheriff’s Office.

The area where the bodies were discovered was initially treated as a hazmat situation due to fears of noxious gasses coming from old gold mines, but the precaution was lifted the following day and Sheriff Jeremy Briese said Thursday that the mines were not near the victims.

The sheriff’s office plans to provide another update when the toxicology reports are complete, but said “there is no current timeframe for that,” and Mitchell warned last week that such testing can take six weeks or more.

“Cases like this require us to be methodical and thorough,” Briese said, “while also reaching out to every resource we can find to help us bring those answers to them as quickly as we can.”

RELATED: Nobody Knows What Happened to Family and Dog Found Dead on Yosemite Hike

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