Blue-green Algae, Fatal To Dogs, Now Carpeting Ponds Throughout UK

Carpets of toxic blue-green algae, some of which can kill dogs within half an hour, are now blanketing many ponds, canals and other shallow water courses as the drought expands across Britain. According to the Environment Agency, the effects of the drought can now be seen right across the UK, with more than 100 instances of algal blooms and fish suffocation reported in the past few weeks. Warm, shallow water holds less oxygen, leaving fish vulnerable to stress, suffocation and disease.

"These are the most suitable conditions for the formation of algal blooms since 1989 and it will get worse if the next few weeks are hot and dry," said Jonathan Newman, head of aquatic plant management at the the Centre for Hydrology and Ecology. "Blue-green algae can be very serious. They produce toxins that are especially nasty for dogs. If dogs lick it they can die in 30 minutes. The toxicity of Microcystis aeruginosa is somewhere between cobra venom and pufferfish."
But he said that it was not particularly dangerous for humans, who would need drink about 250 litres of water containing the algae to be seriously harmed. Yesterday the RSPB warned that without human intervention, many rivers and streams will be emptied of fish later this year as pollutants from farmland become concentrated in increasingly shallow river water.

Thousands of fish have died in the river Idle in Mattersey, west of Sheffield, and in the Counter Drain in Welney, north of Cambridge. More than 20 major fish rescues, including that of about 1,000 wild brown trout from the river Nadder, near Salisbury, have taken place. Angling clubs and pond owners have installed aerators in some rivers and ponds to increase oxygen and reduce toxicity of algal blooms. Low flows in many rivers mean that sea water is flowing further up the river than normal, causing other problems for freshwater wildlife.

EDIT

http://www.guardian.co.uk/uk_news/story/0,,1840852,00.html

They had problems with the deaths of sheep which graze on the banks of the big reservoirs near Heathrow. I fish on pits further back up the Colne Valley and I think the club uses water pumps if there is any risk of an outbreak - keeps the water oxygenated.

> Blue-green algae can be very serious. They produce toxins that are
> especially nasty for dogs. If dogs lick it they can die in 30 minutes.

We don't have a dog (else might have known this already) but we mind
my sister-in-law's when she goes on holiday ... I would have just written
it off as "just another disgusting thing that dogs like to try" ...