May 2, 2014
Duck Hunters reminded of toxic algae in Lake Ellesmere and Lake Rotorua
Hunters are being reminded to avoid contact with two Canterbury lakes this duck shooting season because of toxic algae
(Cyanobacteria).
This year’s duck shooting season officially opens tomorrow, Saturday, May 3.
The Community and Public Health division of Canterbury District Health Board is warning people the toxic algal bloom,
for Te Waihora/Lake Ellesmere near Christchurch and Lake Rotorua near Kaikoura, remains in place as duck shooting season
approaches.
Dr Ramon Pink, Canterbury Medical Officer of Health, says the lakes are still in bloom with concentrations of blue-green
algae (planktonic cyanobacteria) above the levels considered to be safe for recreational activities.
“People should avoid contact with these lakes until the health warnings have been lifted, as there is increased
probability of respiratory, irritation and allergy symptoms from exposure to the high density of the cyanobacterial
material present,” Dr Pink says.
Algae are particularly harmful to dogs and hunters are recommended not to let their pets come into contact or drink
water from the lakes, he says.
“No one should drink the water from the lake at any time. Boiling the water does not remove the toxin.”
Dr Pink says hunters should also wash their hands thoroughly if they come into contact with the lake water or when
handling ducks from the lake.
“Ducks from the lake are fine to cook and eat if their gut has been removed.”
Environment Canterbury continues to monitor the lake and will inform Community and Public Health when it no longer
contains algae concentrations harmful to public health.
Facts about cyanobacteria:
• The algae occur naturally but can increase rapidly during warmer months
• If the water is cloudy, discoloured, or has small globules suspended in it, avoid all contact
• Not all cyanobacterial blooms are visible and toxins can persist after the blooms disappear
• Cyanobacterial concentrations can change quickly with changing environmental conditions (e.g. wind). If a health
warning is in place avoid contact with the water.
For further information visit http://ecan.govt.nz/services/online-services/monitoring/swimming-water-quality/Pages/lake-warnings.aspx
Or contact Community and Public Health on (03) 364 1777.
ENDS