Dogs owners are warned to keep pets out of the water at three popular walking spots in Exeter after tests found toxic blue-green algae.
The Environment Agency (EA) this week confirmed it is continuing to monitor Exeter flood relief channels at Exwick and Trews Weir, while the city council has urged dog owners to keep pets out of the river and canal.
Blue-green algae can prove fatal to dogs, even with swift veterinary treatment. If they drink or swim in water with blue-green algae they can be hit with a mild stomach upset, or suffer life-threatening seizures and death.
An Exeter veterinary surgeon said owners who believe their dogs have gone into blue-green algae water should immediately contact their vet, even if their pet initially appears well because the illness progression can be ‘rapid and serious’.
Rob Somerwill, veterinary surgeon at Estuary vets, in Topsham, said: “Clinical signs to be aware of vary, ranging from mild gastrointestinal upset, to life threatening seizures with collapse or even sudden death possible at higher toxin exposure. Prompt treatment ensures the best outcomes, but sadly, even with the best care, some cases end up being fatal.
“Action to be taken depends on the level and time since exposure, as well as the clinical signs being shown. At the time of noticing a dog covered in algae exiting the water, prevention of licking at the dog of having further material being ingested is of great importance.”
He added: “In a nutshell, rinsing the affected area with clean water, if available, covering the area, or manually preventing your dog from licking it, followed by quick travel to your vet – or the nearest practice if you are away on holiday – will all help improve outcomes.”
The Environment Agency confirmed testing for blue-green algae had taken place in multiple areas of Exeter.
An EA spokesman said: “We are monitoring the blue-green algae at Trews Weir and the Exwick Flood Relief Channel and advise avoiding contact with the water until sampling confirms it is safe.
“Blue-green algae can be harmful to people and pets – please continue to keep clear.”
Mr Somerwill said vet treatment for dogs drinking or swimming in water with blue-green algae could include skin and coat decontamination, internal toxin removal, either making a dog sick, or using binding agents such activated charcoal, to more intensive care in a bid to support life-threatening complications and counteract the toxin’s effects on the nervous system.
He said: “Blue green algae toxicity presents a very real risk to our pet dogs when they are near bodies of water during the warmer months.
“It is worth spending time researching the algae’s appearance, as it varies depending on weather conditions and the algae’s phase.
“Prompt identification and avoidance are the best prevention. If you suspect your dog has been exposed to swimming around algae, always contact your vet. This should be done regardless of clinical signs, symptoms shown at the time, as the illness onset can be both rapid and serious.”
He added: “Please do all you can to educate family and friends, and a polite warning to innocent members of the public who may not be aware that their dogs are entering affected water in affected areas will also be a great public service.”
An example of blue-green algae in water.
Photo: The Environment Agency.
After the canal reopened, a warning remained in place for people, and their pets, to stay away from the water because of nearby blue-green algae.
An Exeter City Council spokesman said: “While blue‑green algae is still present in the wider area, dog owners are advised to keep dogs on a lead near the river and canal and to prevent dogs from entering or drinking from the water.”
The authority said symptoms can take hours or days to appear in people or animals but typically developed within a week of exposure. It advised seeking medical advice, mentioning exposure to blue‑green algae, at any signs of symptoms.
The council spokesman added: “Most exposure causes mild symptoms, but swallowing or prolonged contact can lead to breathing problems, stomach upsets, skin irritation and, in rare cases, more serious effects such as liver damage.”
Blue‑green algae (cyanobacteria) is found in freshwater, salt water or mixed ‘brackish’ water.
In warm, calm conditions, it can multiply quickly and form visible blooms.
