Three dogs reportedly died after coming in contact with blue-green algae in Lake Chabot, according to the East Bay Regional Park District.
Dogs are especially vulnerable to this type of poisoning because they tend to drink lake water and lick algae off their fur.
Some dog owners said they are already taking extra precautions.
"He doesn't drink out of the lake, and we don't accustom him to do that anyway," dog owner Christina Noriega said. "And he stays on the trails. He mainly goes up on the hills and back."
Potential symptoms in dogs following exposure to the blue-green algae can include difficulty breathing, vomiting, and convulsions.
The symptoms can have a very rapid onset, with dogs dying as quickly as within an hour after leaving the water.
