A Family Mysteriously Died While Hiking. It May Have Been Toxic Algae.

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The bodies of a family who went missing after a hike near Yosemite National Park last week were finally found, and a toxic algae bloom is being investigated as the cause of their deaths. 

Jonathan Gerrish, Ellen Chung, their 1-year-old, and their family dog were found deceased in Sierra National Forest near Yosemite National Park Tuesday with no signs of trauma, injury, or suicide. Officials are testing the local waterways for any signs of poisonous algae that’s already been a problem in the area.

“This is a very unusual, unique situation,” Kristie Mitchell, a spokesperson for the Mariposa County sheriff’s office, told the Associated Press. 

The family had recently moved to the area during the pandemic to raise their 1-year-old and enjoy the outdoors, Steve Jeffe, a friend of the family, told the Fresno Bee. Both Gerrish and Chung were experienced outdoors, according to Jeffe. The day was supposed to involve a simple day-hike, but when the family’s babysitter arrived at their house Monday and Gerrish didn’t show up to work, friends started to assume the worst and notified police. 

At first, officials speculated toxic gases may have been seeping out of an old mine 3 miles away from where the bodies were found and investigated under a hazmat warning, according to the Associated Press. But that warning has now been lifted.

“I don’t believe it’s connected to a mine,” Mariposa County Sheriff Jeremy Briese told the Bee. 

Now, the State Water Resources Control Board is investigating the area for toxic algae blooms and lists the area near where the bodies were found as a place of “caution.”  The Sierra National Forest issued a similar warning on July 13 regarding toxic algae blooms, advising visitors to avoid swimming in some bodies of water within the forest. 

Still, the local Sheriff said there is no definite answer yet, and that the investigation is still ongoing. 

Algae blooms are common in many bodies of freshwater and salter but when fertilizer and man-made materials heavy in phosphorus and nitrogen (like city runoff) seep into the water, the intensity of the blooms explodes, especially  paired with rising temperatures. 

In Florida, for example, an infamous algae bloom known as red tide occurs every year, and sharks have been spotted in people’s backyard waterways because their natural habitat is being overrun. Thousands of fish and other marine life have also ended up dead on the beach because of the toxic algae.