Dog dies from algae bloom exposure just 1 hour after swimming in Utah river, National Parks Service says

Officials in Utah have issued a public health warning for part of the Virgin River in Zion National Park after a dog died, following reported exposure to harmful algal blooms on July 4.

The Utah Department of Environmental Quality’s Division of Water Quality and the National Park Service (NPS) received word on Independence Day that a dog died about one hour after swimming in the North Fork of Zion's Virgin River, the park service announced on Saturday.

The pup had been playing in the water and was "snapping" at algae on the rocks, the NPS said. Before passing away, the pooch could not walk and was having seizures – symptoms consistent with possible exposure to cyanobacteria toxins.

Now, scientists believe the pup died from contact with the aggressive algae, KUTV reports.

The Virgin River has since tested positive for a toxin produced by cyanobacteria, and the Southwest Utah Public Health Department has issued a warning for certain parts of the North Fork of the Virgin River.

Though signs will be posted to warn visitors to avoid swimming in or contact with the affected area of the river, parkgoers are additionally advised to not drink the water, keep pets away, avoid areas with algae scum and thoroughly clean fish well, if angling.

The notice does not apply to the Quail Creek Reservoir, Sand Hollow Reservoir or the Santa Clara River basin, the NPS said.

A natural part of aquatic environments, some cyanobacteria can yield dangerous liver and nervous system toxins. In abundance, these toxin concentrations can elevate to levels affecting the health of exposed organisms, including people, pets and livestock.

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