Didymo in the Battenkill

[Simon Chu]

Just saw an article which highlights once again the invasive nature of this algae and I am concerned that lack of knowledge might allow it to continue to spread too quickly.

The article just says to scrub your boats etc and clean your gear.

Unfortunately we have had a bit of experience with it down here and its not something you want in your rivers. Scrubbing your boats is not satisfactory!!!! :-[

Here is a link to our Biosecurity site and the extensive cleaning that is recommended.

http://www.biosecurity.govt.nz/pest-and-disease-response/pests-and-diseases-watchlist/didymosphenia-geminata/cleaning

We are unsure about the eventual effects of this algae and it is another example of globalisation in a way. :'( Its not the end of the world but please take care as once you see it, it won’t be a fond memory to take home of your favourite trout stream.

BTW it can live for several weeks in felt soles, which can incubate it.

[Rich Kovars]

Hey Simon,

I live in Northern New England (New Hampshire).

[charlie kreitler]

I had heard it was in the Connecticut, but hadn’t heard it made it to the Battenkill yet. That’s a real shame.

[Simon Chu]

Hi Rich
We have a more temperate climate down this way and thus far the blooms have been most noticeable during high UV periods (Summer) Without a decent flood event, or as you have snow/ice melt, if may survive the winters quite well but does retreat.

It likes very clean, stable rivers and several rivers fed by lakes and tailwaters have it significantly. The funny thing is, in Sweden, didymo is a positive sign of a healthy river! Native there and just part of the flora.

As anglers we seem to be the most vigilant and perhaps are the biggest stakeholders.

We have had some success with a trial down in Southland but I am not 100% sure of the facts. Its one of my goals next season to head down to the trial site and talk to the scientists there. One of my mates did the felt sole trial and hence I no longer own felts.

I believe it is probably here to stay for us and as you say it is symptomatic of climate change and globalisation. The fish are still there and thus far anecdotally we have had good fishing, even great fishing!, in some of the watersheds in which Didymo is established. However methods of angling and perhaps aesthetic values can diminish.

Trout have been able to spawn in rivers which have didymo mats and it has not killed off all invertebrate life.

I hope your Kayakers and floatboat people come on board in the cleaning department. How do you get on with the NZ mudsnail and whirling disease movements if they use the same watersheds?

[malcolm robertson]

We are covered up with the stuff in the tailwaters of eastern Tennessee.

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