Jun 212018
 

Lindavia Intermedia (Lake Snow.}

I received this email from Brenda Lawson. DOC Freshwater Threats Ranger Kai-Arahi Wai Maori

Hi All,

You are receiving this as you have already had some involvement in the Check Clean Dry campaign in the Central Plateau Area.

THANK YOU for your efforts over the years protecting our NZ freshwater. Truly a precious resource, and we have an abundance – especially at the moment !!!!

I hope that you will share this info – or parts of – to your appropriate contacts, and continue to support the Check Clean Dry campaign in whatever way you can.

I value any ideas and thoughts that you have so please fire those back.

Included below are:

My take on it!

Some quick facts.

links to official pdfs and reports about Lindavia intermedia

MPI website link, and hotline number

Check Clean Dry instructions – latest version

Official media release from Horizons(HRC) and Waikato Regional Councils (WRC).

Please contact me at any time if you need information, and supporting collateral for any publication or event you are involved in.

Ph 0274516985 or email  blawson@doc.govt.nz

Thanks again,

Kind Regards

Brenda

 

OPINION from Brenda….

Key message:     Freshwater users must Check Clean Dry to stop invasive freshwater species including Lindavia intermedia spreading’

We must not lose sight of the key issue – that it is us Humans that can, and have, spread invasive species when we move waterways.

Lindavia intermedia is another example of a foreign invasive species, like Didymo, and it is very disappointing that we now have it.

There are many foreign invasive species already in NZ, with another equally large list of species worldwide that have been recognised as potentially harmful to NZ.

This list includes algaes, weeds, fish and other aquatic organisms.

Lindavia intermedia could, with conditions favourable to its growth, have a very undesirable impact on our freshwater.

Currently scientists do not know what those favourable conditions are – it’s very complicated – more research is underway.

Lindavia could have been in the Taupo catchment since 2005. Gratefully, if present, the conditions thus far have not been favourable to its growth. This may change ……

Its discovery is a reminder to all that we must continue to ‘check clean dry’ when moving waterways internationally, or internally, to stop any invasive species from spreading.

 

From Dave Conley DOC Fisheries manager…..

“Prevention is the only policy, so it’s particularly important for anglers(and all) to use the ‘check, clean dry’ approach to stop the spread of a variety of unwanted invasive species, including Lindavia intermedia,”

 

Lindavia intermedia QUICK FACTS …….

Lindavia intermedia, (the algae) has been confirmed throughout the Central North Island catchment. Lake Moawhango (2018 from 2005 sample)  Lake Rotoaira and Lake Taupo (detected 2018). NOT in Lake Otamangakau !!! Also detected Manawatu/Whanganui.

  Lindavia intermedia, with favourable conditions will ‘bloom’ to become ‘Lake Snow’ which is a very undesirable snotty mucas that will block domestic and industrial filters, cling to stuff including us. Wanaka swimmers have commented that it clings to hair and equipment, and does smell.

Scientists are unsure of exact conditions that cause blooming. It was present in Lake Wanaka for several years before it bloomed and caused problems. Scientific research is continuing…..

There have been no reports of ‘Lake Snow’ in the Central North Island.  

First detected in NZ early 2000s in the South Island. Present in numerous SI lakes. Genetic research suggests it originated from Seattle area, USA.

Other confirmed sites in North Island are: Waikaremoana (2008) Possibly bloomed here but no recent occurrences.

Testing in other NI lakes will continue.

Lindavia Intermedia will not grow in rivers but will be present and transferable if flowing downstream of a Lake – ie the Moawhango, Tongariro, Waikato will be transporting living diatoms

Lindavia Intermedia is a plant. There are no human health risks. It is unlikely to affect the ecological health of lakes.

There is no control treatment for Lindavia intermedia– once it’s here we have it for life !!

 

WHAT DO WE DO …..

We must continue to use CCD ourselves.

Continue to promote CCD to all freshwater users – THANKS you already are doing great at this!!

Contact Brenda or DOC staff for CCD info and collateral

 

WHAT DO WE SAY …..

When moving waterways freshwater users must CHECK CLEAN DRY to stop Lindavia intermedia, and any other unwanted species spreading.

Report any suspicious algal formations – MPI hotline 0800 80 99 66 (on most CCD publications and websites)  www.mpi.govt.nz/check-clean-dry

 

PDFS TO READ/SHARE …..

Horizons webpage

https://www.horizons.govt.nz/managing-natural-resources/plant-animal-pests/lindavia-intermedia

Waikato Regional Council webpage

https://www.waikatoregion.govt.nz/services/regional-services/plant-and-animal-pests/aquatic-pests/lindavia-intermedia/

Otago Regional Council (ORC) info:

               https://www.orc.govt.nz/managing-our-environment/biodiversity-and-pest-control/pest-control/lake-snow

 

Very good report made for ORC– quite simple to understand

https://www.orc.govt.nz/media/3281/ryder-lake-snow-report-9-march-2017.pdf

 

Very scientific report includes genetic identification of Lindavia Intermedia – don’t really need to know but is interesting.

http://www.orc.govt.nz/media/3030/genetics-of-lindavia-in-nz-landcare-report.pdf

 

MPI Hotline

0800 80 99 66  to report suspected exotic freshwater pests (also marine, and diseases in plants and animals)

 

MPI website  

www.mpi.govt.nz/check-clean-dry

 

CHECK CLEAN DRY  ….    (official version from latest media releases)

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.

 

MEDIA RELEASE (from HRC and WRC)

13 June 2018

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.

 

Brenda Lawson
Freshwater Threats Ranger Kai-Arahi Wai Maori

Department of Conservation Te Papa Atawhai
Taupo Office
37 Motutaiko St, Taupō
PO Box 528, Taupo 3330
M: +64 274 516 985

Remember to report a suspected new to NZ organism to MPI’s Exotic Pest and Disease Hotline 0800 80 99 66