Blue-Green Algae That Can Kill Dogs Has Just Been Found in New York City Parks

A toxic blue-green algae that is potentially lethal to dogs has been found in three New York City park ponds––the latest place it’s cropped up after leaving a trail of sick and dead pets across North Carolina, Texas and Georgia.

According to the New York City Department of Parks and Recreation, the blue-green algae was found in two Central Park ponds and another pond in Prospect Park.

Blue-green algae, also known as Cyanobacteria, is a microorganism that is caused by high nutrients, stagnant water, high temperatures and low oxygen, according to the New York City Department of Parks and Recreation.

“Algae is a natural occurrence that blooms heavily in warm weather and sunlight. Most urban ponds have water high in nutrients like phosphorus, which encourage algae growth,” a statement said. “Most algae are harmless and are important parts of aquatic ecosystems, but blooms that produce blue-green algae (BGA) can be toxic.”

Dogs are particularly vulnerable to the toxins because of their tendency to swim and drink contaminated water.

Marit Larson, the New York Parks Natural Resources Group’s Director of Wetland Restoration, tells TIME that the warmer weather associated with climate change could be make the algae more common in some areas.

“There’s not a direct one to one relationship but certainly as we have longer growing seasons and warmer temperatures, its certainly creating conditions that are more favorable to a stronger bloom,” Laron says.

The city recommends that people and their pets stay away from any algae that they may encounter. Officials also suggest that people do not drink from lakes or ponds or swim in the water.

Officials also said that dogs should be kept on leashes and should not be allowed to swim or drink from ponds that are not specifically designated for that.

Human contact with the algae can lead to nausea, vomiting, diarrhea as well as skin and eye irritation and asthma-like symptoms.

In North Carolina, three dogs died this month just hours after being exposed to blue-green algae. Another three reportedly died in a Texas dog park lake after swimming in contaminated water.

In Georgia, one couple posted a warning about toxic algae after their dog got sick just 30 minutes after swimming in a lake. The dog later died at a veterinary emergency room.