Dogs' Deaths Led To Animal Ban At Lady Bird Lake In Austin

AUSTIN, TX — A form of algae toxic to animals but relatively harmless to humans — reportedly causing the death of two dogs — is what prompted city officials to warn residents this week not to take their pets to Lady Bird Lake for the time being.

Although city officials could not confirm the cause for the recent death of two dogs at the lake, they advise pet owners not to allow their animals to swim in or drink water from Lady Bird Lake, city officials said in a press advisory. In light of the canine deaths, the city is implementing the animal ban in an abundance of caution.

The likely culprit: A type of blue-green algae of the genus Oscillatoria that releases a neurotoxin, city officials said. "The neurotoxin in this type of algae can be harmful to pets and people if a sufficient quantity of water or algae is ingested," city officials said. The algae is especially prevalent near Red Bud Isle, covering up to 40 percent of the water surface in that area, officials added.

Previous story: Austin Warns Residents To Keep Pets Away From Lady Bird Lake

"It also tends to be more abundant near shorelines and in areas with low water flow," city officials wrote, noting they launched water quality testing on Sunday. "The situation is evolving. We have not seen any impacts to aquatic species at this time."

While blue-green algae blooms have been seen locally in previous years, city officials said they had been unaware of any ill effects from neurotoxins. "Algae tends to be more prevalent in late summer and early fall and when flows are low," city officials said.

Parks officials reminded residents the body of water — a community focal point in the middle of the city drawing kayakers and sightseeing boat tour enthusiasts — is not a drinking water source. In light of the algae discovery, other waterways from which drinking water is drawn have been assessed for quality, officials said: "Austin Water regularly looks at algae levels on Lake Austin and Lake Travis and has not seen levels of concern for drinking water."

The current algae bloom appears to be confined to algae growing on the bottom of the lake and then floating in clumps to the surface, city officials explained. "Scientists have taken samples of both the algae and the water near the algae in Lady Bird Lake," officials said. "Results from the analysis for the actual presence of the toxin should be available early next week."

Patch reached out to John Faught for a veterinarian's perspective on the issue. He's chief medical officer at Firehouse Animal Health Center, which has five Austin-area locations including sites in Leander and Round Rock. While the city's warning should be heeded, he sought to assuage pet owners' concerns over news of the potentially toxic algae.

Since news broke of the algae blooms, he said Firehouse Animal Health Center clinics have experienced an uptick in activity: "We've seen a few people bring pets in and fielded a lot of phone calls in 24 hours," he told Patch in a telephone interview. And yet: "I don't believe I've seen any actual cases link to the blue green algae at this point."

There actually are two types of toxins released by the blue-green algae, once affecting an animals' liver and another, more serious, neurotoxin that causes paralysis leading affected animals to stop breathing. The latter occurs quickly, and not much can be done to save an animal in the final death throes after exposure. But the more common toxin affecting a dog's liver is eminently treatable although comes with unpleasant symptoms.

"If your dog was in the water over the weekend, and has zero symptoms, it's probably going to be just fine," Faught said. The more benign toxin resulting in liver disease can result in vomiting and diarrhea within a couple of days of exposure. However, treatment options are available if the animal is taken to the vet at the first sign of symptoms — unlike animals afflicted with the neurotoxin, for which no treatment exists.

"Pets and people need to ingest a good amount of algae," Faught noted. But still: "I think we should be cautious until the coast is clear."

The liver-illness-causing version of illness "...has more potential to be treated because the liver is a more resilient organ," Faught said. "It's a slower onset of of damage to the liver. The reason the neurotoxins cause death so quickly is that it paralyzes and causes dog to stop breathing."

Dogs that ingest water contaminated with algae toxins potentially can experience a number of symptoms. On the severe end of the spectrum, symptoms could result in respiratory paralysis and death, city officials said. Pet owners are urged to monitor their dogs and look for these signs within minutes to hours of exposure:

• Excessive drooling, vomiting, diarrhea.
• Foaming at the mouth.
• Jaundice, hepatomegaly.
• Blood in urine or dark urine.
• Stumbling.
• Loss of appetite.
• Photosensitization in recovering animals.
• Abdominal tenderness.
• Progression of muscle twitches.
• Respiratory paralysis.

"Until we have more information, we strongly advise that pets stay out of the water," city officials emphasized. "At this time, we have no reason to believe that boating is unsafe. However, people should not be swimming in Lady Bird Lake. It is illegal. When out on the lake, people should take care to avoid ingesting water or coming into direct contact with the algae."

The degree of risk to human exposure, such as through accidental swallowing of lake water, cannot be known until the tests results are available and analyzed, officials said.

For more in-depth information related to algae bloom toxicity in dogs, read an article on the wag! website by clicking here. We also found a video explaining the science behind the algae that makes it potentially toxic:

For a deep dive into the subject of toxic algae, check out this 30-minute episode from ChangingSeasTV: