Didymo

Important information for freshwater anglers bringing used fishing equipment to New Zealand

To slow the spread of the invasive alga Didymo and other aquatic pests in New Zealand waterways, MAF Biosecurity New Zealand requires all used freshwater fishing equipment brought into New Zealand to be clean and dry.

From mid-October 2007 MAFBNZ’s Import Health Standard for Equipment associated with Animals or Water will be updated. MAFBNZ staff will now treat all used freshwater fishing equipment they determine or suspect is NOT COMPLETELY DRY (inside and out), regardless of whether it has been cleaned before coming to New Zealand.

Felt-soled waders and boots are of particular concern and have now been banned. Recent research has revealed these items pose a particularly high-risk of spreading Didymo as they are likely to come into direct physical contact with Didymo cells (e.g., stepping on or brushing against algal mats). The thick, absorbent and slow-drying nature of the material also encourages cell survival, increasing the risk of Didymo spread between waterways.

Depending on the item, there are a number of treatments available, including cleaning/soaking in a solution of detergent and water, soaking in hot water, or freezing until completely solid. MAFBNZ staff will determine the most appropriate treatment for the item.

Treatment for absorbent items takes time and will most likely take place outside of the airport. If it is not feasible for the owner to wait for treatment to be completed, they will have to make their own arrangements to collect the item or have it shipped to their New Zealand, or home address.

To avoid this inconvenience, anglers coming to New Zealand should consider bringing rubber-soled footwear.

New Zealand has some of the most pristine rivers and lakes in the world. To help us to keep it that way, freshwater users must ‘Check, Clean, Dry’ aquatic equipment between use in different waterways – regardless of location and perceived Didymo risk.

Didymo has only been found in the South Island. To protect the North Island, a controlled area notice requiring cleaning of aquatic equipment when moving from the South Island to the North Island is in force.

Detailed cleaning instructions and more information about Didymo are on the MAFBNZ website www.biosecurity.govt.nz