Local Govt | National News Video | Parliament Headlines | Politics Headlines | Search


Lake algae found in Waikato and Manawatū-Whanganui regions

Lake algae found in Waikato and Manawatū-Whanganui regions for first time

Lindavia intermedia, a microscopic freshwater algae species, has been found in the Waikato and Manawatū-Whanganui regions for the first time. Its discovery prompts a reminder to all water users to ‘check, clean, and dry’ when moving between waterways.

Lindavia intermedia is an extremely small freshwater algae species that floats in the water column of lakes and has the potential to create lake snow. It poses no risk to food sourced from lakes or to human and animal health. Currently there is no known impact on the health of lakes, however further research is needed.

Lindavia intermedia was discovered in the North Island in Lake Waikaremoana in 2008. Early this year, researchers from NIWA were trying to figure out when lake snow first arrived in the country and tested historic water samples. They confirmed with Horizons Regional Council late last month that Lindavia intermedia was present in samples taken from the Moawhango River.While the positive samples were taken 5kms and 40kms downstream of Lake Moawhango, it is most likely to be present in the lake.
Following conversations with Waikato Regional Council, iwi, and other stakeholders, further investigation has indicated it is also present in Lake Rotoaira and Lake Taupō. Meanwhile, testing is underway on water samples collected from lakes downstream from Lake Taupō.

Horizons Regional Council’s samples from Lake Otamangakau have come back clear, however the council will undertake additional testing at popular fishing and recreational waterways such as Lakes Wiritoa, Dudding and Namunamu.

Horizons freshwater scientist Michael Patterson says that where Lindavia intermedia has been found it’s likely this algae species has been in these lakes for more than a decade. This is because the historic samples recently retested are from as far back as 2005.

“Over that time, the Lindavia intermedia has not produced lake snow effects as far as we are aware and we have no evidence of it causing issues to lake users,” says Mr Patterson.

“There is currently no known way of removing Lindavia intermedia once it is present in a lake or waterway. The conditions necessary to produce the lake snow effect are not clear, more research is needed.”

“As lake snow produces mucus-like strands of slime which hang and drift under the water, sticking to fishing gear, boat hulls, swimmers, and can clog boat, industrial and domestic water supply filters, we’re keen to prevent it,” says Waikato Regional Council biosecurity officer Paul Quinn.

“Water users play a critical part in protecting their favourite waterways,” says Mr Quinn.

“The key is to always check, clean, then dry any equipment that comes into contact with the water, between every waterway, every time.”

While other waterways may also have Lindavia intermedia, rivers and streams with fast moving flows are believed to be less than ideal environments for the algae to thrive.

Both regional councils are looking at options for adding Lindavia intermedia testing to their regular monitoring programmes and are working with stakeholders and researchers to find out more about what conditions influence the growth of the algae.

“In particular, we are keen to understand what causes it to produce lake snow like it has in some South Island lakes,” said Mr Quinn.

NIWA research for lake snow presence in the South Island identified that the Check, Clean and Dry methods used for didymo are also appropriate for use with Lindavia intermedia and lake snow.

Cleaning options are:
Dishwashing detergent or nappy cleaner – 5% solution (500mls diluted to 10 litres in water). Soak or spray all surfaces for at least 1 minute, or
Bleach – 2% solution (200mls diluted to 10 litres in water). Soak or spray all surfaces for at least 1 minute, or
Freezing until solid.

Drying can be used as stand-alone treatment for non-absorbent items if you take great care to:
make sure gear is completely dry to touch, inside and out
leave dry for at least another 48 hours (after drying), before entering a different waterway.

To find out more on how to protect our waterways, visit www.mpi.govt.nz/check-clean-dry.

© Scoop Media

Parliament Headlines | Politics Headlines | Regional Headlines

World Refugee Day: What 7 Former Refugee Kids Love About New Zealand

New Zealand resettles 1,000 refugees each year (a number set to increase to 1,500 by 2020). More than half of these people are children under 18.

RASNZ, a specialist mental health and wellbeing service provider for people from refugee backgrounds, wanted to know what some of these young people thought of their new lives as kiwis.

They asked 7 members of their specialist youth service (along with two staff members who work with refugee background youth) how they felt about New Zealand – and filmed the responses. More>>


DHBs: Nurses Plan Strike Action For Next Month

Nurses across the country have confirmed a notice of a 24-hour strike, starting on 5 July. District Health Boards (DHB) were working on contingency plans following a notice to strike by the New Zealand Nurses Organisation. More>>


Gordon Campbell: On Tomorrow’s EU Trade Talks With NZ

One of the world’s most influential bureaucrats – the European Union’s Trade Commissioner Cecelia Malmstrom – will be in New Zealand tomorrow to launch the formal process of negotiating a bilateral trade pact between the EU and New Zealand. More>>

Oranga Tamariki: Children's Ministry Shifts Away From Putting Kids In Care

Children's Minister Tracey Martin is signalling a shift away from putting children into care, and towards intensive intervention in a child's home. More>>

But No Way To Tell Why: Significant Drop In HIV Diagnoses

A new report shows that for the first time since 2011, the number of annual HIV diagnoses in New Zealand has fallen. But without funding for a repeat of ongoing surveys to monitor changes in behaviour, testing and attitudes, health workers can’t be sure what’s driving the decrease. More>>


On Her Majesty's Public Service: Inquiry Into Spying Claims Extended To All Govt Agencies

In March, State Services Commissioner Peter Hughes announced an inquiry after it was revealed the firm spied on Canterbury earthquake claimants for Southern Response. The inquiry was furthered widened to include the Ministry of Business, Innovation and Employment, who had been spying on Greenpeace staff. More>>


Gordon Campbell: On A New Obstacle To The 'Hit & Run' Inquiry

With a minimum of publicity, a High Court ruling hit the tarmac last week concerning the use of security information that – if left unchallenged – could well cripple the recently announced government investigation into the Hit & Run allegations. More>>

DHB Offer Rejected: NZNO Seeking Urgent Mediation

The latest revised DHB MECA offer has been strongly rejected by NZNO members. However, Industrial Services Manager Cee Payne says that as nursing and midwifery is an essential service, mediation or facilitation will begin with urgency. More>>





Featured InfoPages