The dangers of blue-green algae

By Hayley Hamilton-Herbert, owner of Simply the Pets

An outbreak of toxic blue-green algae has been confirmed at Frensham Great Pond at Frensham Common in Surrey, a popular bathing spot for families to visit during the summer holidays. The algae, which can cause skin and stomach problems in humans, is extremely dangerous – often fatal – to dogs and other wildlife.

Blue-green algae is a naturally occurring bacteria which is usually found in non-flowing bodies of water, such as lakes, ponds and rivers. Hot weather and heavy rainfall can result in the bacteria growing excessively, causing a ‘bloom’ to form on the water’s surface.

Dogs are at risk of poisoning if they drink or swim in contaminated water. The harmful toxins can stop their liver from functioning properly, leading to organ failure.

With warmer weather and the school holidays upon us, many people will be thinking of taking their dogs to water spots to cool off and have some fun. Here are our tips for keeping them safe from blue-green algae poisoning.

How to spot blue-green algae

Knowing what to look for will help you to prevent your dog from coming into contact with it:

  • • Green/blue scum on the water’s surface
  • • Green/blue streaks in the water, which can look a bit like paint
  • • Green or brown clumps floating on the surface, resembling seaweed
  • • Cloudy water with a green/blue/brown appearance.
  • • Green flakes or brown dots
  • • Foaming on the shore’s edge, looking a bit like sewage
  • • Dead fish or wildlife in the water

Symptoms of poisoning

Blue-green algae poisoning can take effect after just 15 minutes, but may take a few days to develop. Watch out for these symptoms:

  • • Drooling
  • • Disorientation
  • • Diarrhoea
  • • Vomiting
  • • Increased thirst
  • • Collapsing
  • • Seizures
  • • Breathing difficulties

Help! My dog has been exposed, what should I do?

If your dog shows any of the above signs after drinking or swimming in water, contact your vet immediately – the sooner they receive treatment, the better the outlook. There is no antidote for the toxins produced by the algae but if caught early enough your vet will likely induce vomiting and attempt to flush the toxins from their body.

Until you can get your dog to the vet, wash your dog off with clean water to remove toxins from their coat and prevent your dog from licking their fur to reduce further intake of toxins.

Prevention is better than cure

You can protect your dog from blue-green algae by:

  • Checking the water every time before letting your dog go in
  • Using extra caution around stagnant water
  • Carrying water with you for them to drink instead
  • Watching out for warning signs and checking local council websites for up-to-date information

Think you’ve spotted blue-green algae? Ring the Environment Agency incident hotline on  0800 80 70 60.

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