25/06/2026
There has been a report of suspected blue-green algae in Frensham Great Pond, Surrey. Blue-green algae can be fatal to dogs.
Blue green algae tends to grow in stagnant/slow-flowing water such as ponds, streams and lakes. It can be very difficult to spot, so keep an eye out for:
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, that look a bit like seaweed
Cloudy water with a green/blue/brown appearance.
Green flakes or brown dots
Foaming on the shore’s edge, which can look a bit like sewage
Warning signs
Dead fish/wildlife in the water
Blue-green algae poisoning can cause symptoms as early as 15 minutes after ingestion, but can be days after. Symptoms range from vomiting, diarrhoea and breathing difficulties, to seizures, collapse and death.
If you suspect your dog has been exposed to blue-green algae, its vital to call your vet immediately.
https://www.pdsa.org.uk/pet-help-and-advice/pet-health-hub/conditions/blue-green-algae-poisoning-in-dogs
Read our vets' advice on blue-green algae poisoning in dogs, including symptoms and when to call your vet.