AUSTIN (KXAN) — Continue to keep your pets out of the Highland Lakes, the Lower Colorado River Authority says.

LCRA received test results Wednesday that revealed cyanotoxins in Inks Lake, Lake Marble Falls and Lake Travis. Cyanotoxins are produced by blue-green algae and can be fatal to dogs. Previous reports of dogs getting sick, with one report of a death, prompted LCRA to run tests.

The tests were taken between March 16-17 in the aforementioned lakes, as well as Lake Buchanan and Lake LBJ, the agency said in a press release.

“We encourage people in the strongest terms possible not to let dogs play near algae in the lakes,” said John Hoffman, a LCRA executive vice president. “Our tests show what was present at the specific site we tested on the day we took the samples, but conditions can change.”

Low concentrations of cyanotoxins were found in algae blooms from the shoreline near the Inks Lake State Park boat ramp and at the Cottonwood Shores bot ramp in Lake Marble Falls. The level of toxins found in those places was “significantly lower” than what was detected at Hudson Bend in Lake Travis. The toxins were not found in water samples taken from Inks Lake and Lake Marble Falls, however.

Tests showed there are also cyanotoxins present at Travis Landing, an area near Hudson Bend where two other tests also showed toxins in the water. The most recent tests showed lower levels of the toxins than previous tests, LCRA said.

KXAN’s Tahera Rahman spoke with the breeder of a dog that died after swimming near Hudson Bend in February. The breeder said the dog had a seizure, one of the symptoms of cyanotoxin exposure, and eventually died of cardiac arrest.