Dog owners are being warned to take extra precautions after a toxic blue-green algae has been discovered in UK waters.

The warning comes after a dog in Conwy, Wales, sadly collapsed and passed away last week from suspected blue-green algae poisoning. Blue-green algae naturally occurs in inland waters, estuaries and the sea, however contact with the toxic bacteria can cause rashes and illnesses to both humans and dogs.

In April last year, a Cocker Spaniel sadly died of suspected blue green algae poisoning after swimming at a lake in Hampshire. Elsewhere, the RSPCA also confirmed the death of a swan after being found in toxic waters.

"As we head towards the warmer months of the year, and spend more time outdoors with our canine companions, it is important that pet parents are aware of the dangers blue-green algae can pose to dogs," says Sean McCormack, head vet at tails.com.

"While blue-green algae may not look dangerous, because a lot of shallow water is filled with green stuff, it can actually be toxic to dogs if they swim in or drink from contaminated waters. This is because blue-green algae blooms produce harmful toxins that can stop a dog's liver from functioning properly."

What is blue green algae and how does it differ from green algae?

"While blue-green algae sounds the same as green algae the two are vastly different. First and foremost blue-green algae is a form of bacteria that is sometimes referred to as 'cyanobacteria', and most of the time cannot be seen by the naked eye," adds Sean.

"However, blue-green algae can sometimes be identified if it clumps together and blooms because more often than not, water will turn a pea green soup colour. Green algae is more of a stringy like substance that can be draped over sticks and picked up more easily."

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Blue-green algae

How can toxic algae affect pets?

Dogs can easily ingest water from lakes and rivers when stopping for a drink or swim. With many owners heading outdoors for walks during the summer, it's vital you spot the signs of algae ingestion early.

"When our dogs encounter blue-green algae, they may experience some of the same symptoms we do including vomiting, but they can also have a lot more severe side effects," says Sean.

Some signs include:

    • vomiting
    • diarrhoea
    • drooling
    • disorientation
    • trouble breathing
    • seizures
    • blood in faeces

What causes toxic algae and what does it look like?

Algae bloom can occur in freshwater lakes, as well as other marine environments. It is a type of bacteria (cyanobacteria), which forms as a result of an excess of nutrients. The water colours to spot are green, yellowish-brown and red.

According to Science Daily, "when the dissolved oxygen content decreases, many fish and aquatic insects cannot survive. This results in a dead area."

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Harmful algal blooms in polluted water

Toxic algae appears more when the warm weather increases, as the heat can speed up its growth.

Dr Mike Bowes, from the Centre for Ecology & Hydrology said to the BBC: "They flourish in hot weather and dry conditions which speeds up growth. Blue-green algae are potentially fatal to animals. They produce toxins that can cause damage to the liver or nervous system."

If you are worried your dog has been in algae-infected waters, head to your local vet immediately.

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Lisa Joyner
Deputy Daily Editor, Country Living and House Beautiful

 Lisa Joyner is the Deputy Daily Editor at House Beautiful UK and Country Living UK, where she's busy writing about home and interiors, gardening, dog breeds, pets, health and wellbeing, countryside news, small space inspiration, and the hottest properties on the market. Previously, she has written for Conde Nast Traveller, House & Garden and Marie Claire magazine. Lisa studied at University For The Creative Arts, where she completed a BA in Fashion Journalism.