Officials Release Cause of Death of California Family Found in Sierra National Forest

Both the hiking community and local authorities were left baffled earlier this year after reports of four mysterious deaths along a California hiking trail circulated through the news.

After months of investigating, officials have determined the cause of death for all three family members, as well as their dog, to be heat and weather-related—specifically, hyperthermia and probable dehydration.

“For Mariposa County, this is rare,” Sheriff Jeremy Briese told reporters in a press conference on October 21st, “This is the first hyperthermia cause of death that I’ve witnessed here in 20 years.”

Although both Ellen Chung and her partner John Gerrish we described as experienced hikers, temperatures along the Savage-Lundy hiking trail – a remote spot about 200 miles east of San Francisco – rose to 109°F during the day of their hike in August 2021.

Upon the discovery of their bodies by a search and rescue team, 45-year-old John Gerrish was found in a seated position with their one-year-old daughter, Miju, in his lap and the dog by his side. Thirty-year-old Ellen Chung was found a little farther up the hill. All family members were deceased at the time of their discovery.

Although the family was only 1.5 miles from the trailhead and had relatively full water bottles in their possession when their bodies were found, authorizes say they feel confident in what they are determining to be the cause of death. The water inside their bottles was tested, but came back with no toxins and appeared to be tap water, according to police.

At the time of their death, the scene was treated as a hazmat area with speculations about toxic algae or gas from abandoned mines being the culprit. In September, Sierra National Forest closed trails near where the family died, citing “unknown hazards found in and near the Savage Lundy trail”. However, as months went on, officials say they found no evidence to support this claim. Law enforcement ultimately ruled out a number of theories including drugs, suicide, carbon monoxide, and lightening.

Given the unusual circumstances of their death with the entire family being found deceased, more than 30 local, state, and federal agencies were involved in searching for answers. The FBI is currently analyzing a cellphone that was found with the family, and investigators are hopeful that it will provide additional information about what unfolded on the trail that day.

The couple had moved to Mariposa county in March 2020 and were described as becoming “avid outdoors people” after their move by friends and family. Gerrish was originally from England and worked as an engineer at Snapchat, while Chung worked as a yoga instructor and was studying to be a therapist.

In a statement by the Gerrish and Chung families, they said that the death of their loved ones has been a “pain almost beyond words”, and that it was “worsened by its mysterious nature”. They thanked the countless agencies and individuals for their work on the case and efforts to provide answers.

“Our hearts will never forget the beautiful lives of Jonathan, Ellen, Miju and of course, Oski,” the statement said. “They will remain with us wherever we go and in whatever we do. In the future, when we sit beneath the trees listening to the wind soaring through the branches, we will hear them and we will remember.”

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