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THE THREAT: Didymo is an invasive freshwater alga that can form massive blooms. Didymo can smother stream beds and adversely affect freshwater fish, plant and invertebrate species by depriving them of habitat, and also impact recreational opportunities. It is not considered a significant human health risk, but in recent years has been spreading to previously unaffected areas in North America, Europe and Asia, and has been detected in New Zealand. This species historically formed blooms in fast-flowing, cold, clean waters but now didymo is increasing its ecological range. Recent research shows that many countries across the globe provide suitable habitat for didymo to thrive.
DESCRIPTION: Didymo is a freshwater diatom (type of alga) that uses stalks to attach to stream bed material. It forms a thick mat which smothers rocks, submerged plants and other materials. As the stalks lengthen, the beige/brown mats shred into the stream and are sometimes washed white at the ends, looking similar to tissue paper. Although they appear slimy, didymo mats feel like wet wool.
RISK OF SPREAD: Recreational equipment, including boats, kayaks, lifejackets and fishing gear (particularly waders) is the most likely way for didymo to spread. Didymo can remain viable for several days if kept moist,and can be transferred in microscopic form on equipment to new waterways. Infection may only need a single cell. This means fishermen travelling internationally contribute to the risk of spread. It is not possible to eliminate didymo from a waterway once it has become affected. Decontaminating equipment between use in different freshwater systems is the key to preventing further spread and leaving an environment for all to enjoy.
DONíT SPREAD DIDYMO: Where possible, equipment should be restricted to use in a single waterway. If this is not feasible, we suggest the decontamination methods of CHECK, CLEAN, DRY.

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Re: [Dryrod] DIDYMO In reply to
Clean * Inspect * Dry

It's the solution whether the issue is zebra mussels or New Zealand Mud Snails or any of these other aquatic hitchhikers. Thanks for raising awareness, Dryrod!