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.

This year’s duck shooting season officially opens on Saturday, May 5.

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.

Canterbury Medical Officer of Health Dr Ramon Pink 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.

“If you experience any of these symptoms visit your General Practice team immediately and please let your doctor know if you have had contact with the lake water.”

Dr Pink says algae are particularly harmful to dogs and hunters are recommended to not let their pets come into contact or drink water from the lakes.

Shooters should also wash their hands thoroughly if they come in 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 the public will be advised when the Lake is clear of concentrations of algae deemed of public health significance.

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.