Toxic algae found in Southland river
Dog owners in northern Southland are being warned not to let their dogs eat a toxic algae which has been found in a river.
The algae, which looks like a cow pat, has been found in Winding Creek and the Waikaia River.
Rebecca Morley of Northern Southland Vets said a bearded collie was bought in to the clinic on December 30 after it vomited and suffered from seizures.
Its owner had noticed it eating the algae, she said.
"The dog didn't present with signs of any other illness so it's likely that it was the algae."
It made a full recovery after being given fluids and activated charcoal.
"No other dogs have been bought into us so we're not sure if there have been any other cases."
Environment Southland scientist Nick Ward said the algae was cyanobacteria, which lived in stoney stream beds.
The algae can produce toxins that are harmful to animals and humans when eaten or even licked, or when water containing the toxins is swallowed.
Some people will have an allergic reaction just touching it.
"The conditions that set this off are complex. Conditions favourable to its growth occurs when nutrients are elevated and extended lower flow periods occur with warmer weather. When higher flows come down the systems the stuff gets ripped out and effectively resets the accumulation of growth.
"Best thing to do is be on the look-out for high coverage and also algae breaking off rocks and gathering on the edges of rivers – dogs will play and drink from the areas to the edges."
ES staff monitors coverage and informs Public Health South, who then notify the public of the health risk.
"Some staff visited Piano Flat and Waikaia last week and have found that Cyanobacteria is almost at the point of informing Public Health South, but not at Waikaia."
Cyanobacteria are widespread in Southland, being present in 96 per cent of monitored sites in 2009.
Southern District Health Board medical officer of health Dr Derek Bell said any confirmed poisoning arising from the environment is a notifiable condition.
"Public Health South have not been notified of any cases or algal problems in this location recently. It is possible that there may be some permanent signage at the river that refers to the periodic risk."