Death of at least one dog prompts warning about toxic algae in B.C. lake

A veterinary clinic in the B.C. Interior shared this image of blue green algae after a dog died from suspected exposure in July of 2025. (Credit: Facebook/kelownablackmountainvet)

The B.C. SPCA is out with a warning for pet owners after “at least one” dog’s death and multiple canine illnesses linked to toxic blue-green algae in a lake in B.C.’s Interior.

The animal welfare organization posted an alert to social media Wednesday saying one fatality has been confirmed this month in a pet that came into contact with toxic cyanobacteria, in Nicola Lake.

“These harmful algae blooms can produce toxins that are extremely dangerous to pets. Even a quick swim or lick of contaminated water can cause serious illness,” the B.C. SPCA’s post said.

“Before letting your dog swim or drink from lakes, ponds, or streams, check for posted advisories and avoid any water that looks discoloured, scummy, or has a strange smell.”

An alert from the province’s chief veterinarian also notes there have been two suspected cases of poisoning reported this July in pets after swimming in Nicola Lake.

The potentially deadly blooms are most common in stagnant freshwater bodies like lakes and ponds. However, they can also develop in faster-moving rivers and streams, and sometimes in places like fountains or birdbaths, according to the alert.

Signs cyanobacteria may be present include: “discoloured water, ranging from green, to blue, red, purple or brown; unusual water surface textures that resemble paint or streaks, pea-soup, foam, scum, grass clippings, clumps or mats; and the presence of dead wild birds or fish.”

But the notice also notes the blooms are not always visible and the presence of toxins can’t always be determined just by looking at the water.

“Blooms are not always obvious, and you can’t tell whether a bloom is toxic by looking at it. If you suspect there is a bloom you should assume toxins may be present,” the advisory continues.

“Toxins can also persist after a bloom has dissipated or moved, so if there has been a recent bloom in the area, you should use caution before entering the water, even if the bloom is no longer visible.”

The blooms are also toxic to humans, but pets are particularly vulnerable to serious illness and fatal poisoning due to the amount of water they ingest while swimming or playing.

BC Parks has an advisory posted for Nicola Lake, saying “a number” of algae blooms have been reported, and urging people to keep their pets out of the water.

More information on the toxic algae and is available online.

https://www.healthlinkbc.ca/healthlinkbc-files/cyanobacteria-blooms-blue-green-algae