Felt Sole Wading Boots Pose a Major Didymo Risk

29 January 2007

While anglers are advised to “Check, Clean and Dry” their equipment between different waterways, recent research has revealed that felt-soled boots or waders are virtually impossible to effectively decontaminate. Regional manager of Fish and Game NZ, Neil Deans, says “the risk of spreading didymo with felt-soled waders (or other dense absorbent materials which stays damp) is extremely high and as a result, anglers are advised to avoid the use of felt-soled boots and waders this summer. In particular, felt soled boots should not be used in waterways known to be contaminated with didymo, such as the Buller and Gowan Rivers, unless they are only to be used in those rivers.” He says, “While this may seem excessive, the threat posed by felt soles is so significant and the implications of didymo so serious, we cannot ignore this research that has recently become available”.

While freezing until solid or totally immersing in hot (50°C) water containing 2% dishwashing liquid or nappy cleaner for 30 minutes has been found to be most effective at decontaminating felt soles, Mr Deans said “Fish and Game staff recommend the use of rubber soled alternatives that dry rapidly and are easily cleaned. Even these drastic measures are not certain to disinfect felt soles.” If anglers are to use felt-soled boots, Mr Deans urges “that they are restricted to only one river, so as to minimise the risk of spread of didymo (or any other pest or disease).” All other equipment should be scrubbed and soaked for at least a minute in either hot water (60°C), a 2% solution of household bleach or a 5% solution of either salt, nappy cleaner, antiseptic hand cleaner or dishwashing detergent.

Despite all the concerns about didymo and its spread, Mr Deans says “Anglers in the Nelson Marlborough region are fortunate that didymo has not spread into most of our waterways. Recent floods in the Buller and Gowan have significantly reduced the amount of didymo in these rivers at present. These and other rivers still offer plenty of fishing opportunities. The Motueka and Wairau are fishing particularly well this year with some fish in excellent condition this year. If the Motueka fishes as well as last year, anglers can look forward to a great season, weather permitting.”

Mr Deans reminds anglers that rangers will be on the water over the summer and that anglers are required to carry their licence on them while fishing to produce to rangers. He also encourages anglers to “get out and make the most of the fishing”, but adds a caution “that it is up to individuals to ensure didymo doesn’t spread further. Make sure you take care not to limit your own future fishing opportunities.”