Check clean dry to keep Gisborne didymo free
An awareness campaign to combat the threat of didymo or ‘rock snot’ in Gisborne waterways is underway over summer.
Didymo is a microscopic algae that can be spread through a single drop of water. It can survive a long time in moist
conditions out of waterways. It is not in local lakes and streams yet but every freshwater user needs to take
responsibility for keeping didymo out.
Didymo awareness advocate Olivia Davidson is visiting local freshwater spots talking to people about the importance of
checking equipment, cleaning it and drying it properly before leaving the water. ‘This is the best way to prevent didymo
and other freshwater pests from spreading into our clean waterways,” says Ms Davidson.
“Even if you cannot see it you could be spreading it that is why it is so important to ‘Check Clean Dry’ every time.”
‘Check Clean Dry’ is a habit all New Zealanders and visitors need to adopt when boating, fishing, water skiing in our
freshwater. The didymo algae have already spread throughout some rivers, streams and lakes in the South Island, and
there has been a major effort to stop it getting into North Island waters.
Olivia is originally from Gisborne and is currently a student at Canterbury University studying Natural Resources
Engineering. She loves her summer job. “I am enjoying being outdoors, talking to people and making them aware of water
quality issues and what they can do to make a difference. I visited Matawai, Motu, Rere and Tiniroto schools in December
to speak to classes about aquatic pests like didymo, lagarosiphon (curly oxygen weed which is bad at Waikaremoana at the
moment), and koi carp (a fish that looks like a large goldfish.)”
“Many of the students were familiar with the predator free fence that has been put up in the Motu area to protect kiwi
so they understand about pests. The problem with our lakes and streams is that we can’t put up a fence to keep rock snot
and curly oxygen weed out. We also talked about what to do with unwanted goldfish. They mustn’t be released into our
waterways – they should be given to a pet store instead.”
Didymo is nicknamed ‘rock snot’ as it forms a thick slime on the rocks and base of a river. It harms native fish, trout,
plants and insects. Rivers, streams and lakes become really unpleasant to go swimming, boating or fishing in. It is
invisible in water until it gathers to form a smelly, slimy mat.
Trevor Freeman, environmental services manager with Gisborne District Council is grateful for the Ministry for Primary
Industries funding that has enabled Olivia to spread the message in this district and down to as far as Wairoa. "Aquatic
pests are very difficult to eradicate, if not impossible. Council and the Department of Conservation have collaborated
to reinforce the ‘Check Clean Dry’ message.
Any suspected sightings of the algae in the Gisborne region should be reported to the Ministry for Primary Industries on
0800 80 99 66.
ENDS