Media Release - 8 October 2007
Toxic blue-green algae in Lake Forsyth/Te Roto o Wairewa could potentially kill children and has killed dogs, according to a scientist who has been working on measuring the lake’s toxicity.
CPIT Foundation-funded researcher Dr Barbara Dolamore has been investigating the environmental effects of toxic cyanobacteria on the lake since 2004.
“The water may look safe but it isn’t. Livestock and dogs have already died from drinking water from the lake and the local Runanga don’t want this happening to people who live near the lake – or to visitors to the area,” says Dr Barbara Dolamore, a senior lecturer in biochemistry and molecular biology at CPIT.
“The local Rununga has sole eeling rights and since the nodularin toxin is not destroyed by cooking, accumulation of the toxin in fish could also be hazardous to people’s health,” she says.
Wairewa Runanga chairperson Robin Wybrow says the Foundation’s research project alerted the community to the dangers of the lake.
“The research is incredibly valuable across all areas. She has made us aware of potential health issues and spurred us to do something about it,” says Robin.
The Runanga has applied for a resource consent to construct a groyne beneath the cliffs at the north end of Kaitorete Spit to create an opening into Lake Forsyth.
“This process is about reconnecting the traditional food chain by harnessing the ocean’s natural energy and tidal patterns to allow the lake to breathe,” he says.
“If we can keep an opening at least 80 per cent of the time, we may be able to improve the lake’s water quality and save the eel fishery.”
Wairewa Runanga met recently with the local community to discuss how the toxins affect humans, livestock and eels, fish and other food sources.
The safety of visitors to the area concerns the Runanga because they do not want to see anyone suffer from illness, or even death, due to the lake’s toxicity.
“In the past a lack of good information meant that managing public safety was difficult, particularly in recent years with the rise in recreational activities, the opening of the rail trail and increasing tourism in Akaroa,” says Robin Wybrow.
“Dogs, sheep and cattle have already been killed by the toxins in the lake and we don’t want this happening to any visitors,” he says.
“We need to do something about our lake now. In the long-term we want Te Roto o Wairewa to be an asset to the local community and to Canterbury as a whole.”
The toxic bloom, nodularia spumigena, usually occurs over summer but is often there for up to seven months of the year, says Barbara Dolamore.
The research into toxins at Lake Forsyth has been funded by the CPIT Foundation. Dr Dolamore has investigated bioaccumulation of toxin in eels and is trialing a unique method (developed at the Cawthron Institute) to monitor water toxin using porous synthetic resin-filled sachets attached to buoys. These bags passively adsorb biotoxins over a set period of time and are then processed and analysed. This year she will look at accumulation of toxins in lake sediments.
The CPIT Foundation contributed $7760 to the latest research proposal which was integrated into the larger restorative community-based Te Wairewa Restoration Programme led by Waiwera Runanga.