Click and watch the YouTube video above and watch how bad this can affect trout rivers!
 

What is this problem that is infecting so many trout streams and lakes around the world? I first read about Didymo online in a fishing article stressing the importance of not spreading this disease to other streams and lakes. The article stated that felt soled wading boots was the main cause of the spread. The author stressed that in the very near future felt soled wading boots could be banned. I have never heard of this disease but I have seen signs of it in the Bow River where I fish regularly. So what is it and how can we help stop it?

Rock snot which it is also referred to is algae bloom that cuts off oxygen levels to affected streams and lakes. Algae cells bond together to form large mats, preventing the insects that fish usually eat from living in their natural environment and limiting the food fish can access. “Bad cases cover the bottoms of rivers like shag carpeting and this allows water flow between the water and sediments and the sediments may not receive the proper oxygen exchange,” said Leland Jackson, a professor in the U of C’s department of biological studies. “We’re going to use genetic fingerprinting to determine if it’s native to Alberta or non-native.”

Researchers from Parks Canada and the University of Calgary have teamed up on a two-year study to determine where the Didymosphenia geminata, also known as didymo or rock snot, began growing and stop it from harming the ecosystem further.

How do I identify Didymo?

The alga attaches itself to the streambed by stalks and can form a thick brown layer that smothers rocks, submerged plants and other materials. It forms flowing ‘rats tails’ that can turn white at their ends and look similar to tissue paper. As the ‘tails’ of the algae get longer they become white in color.

How do we prevent the spread of Didymo?

Here are some suggestions to use. All river users are urged to take care not to spread the alga from one waterway to another. Before you leave any river or lake:

Check – remove all visible threads or clumps of weed and algae from gear and clothing. Felt soled wading boots should be paid close attention too as they will carry the most algae.
Clean – soak or scrub all items of equipment for at least one minute with either:

A: Hot (60 degrees C) water, or
B: 2% solution of household bleach, or
C: 5% solution of salt or nappy cleaner, or
D: 5% solution of dishwashing detergent, or
E: 5% solution of antiseptic hand cleaner.

Dry – after cleaning equipment, or if cleaning is not practical (e.g. animals), dry until touch and or dry then leave for a further 48 hours before entering another waterway.
Let’s do our part in stopping the spread of this could be catastrophe in our rivers, lakes and oceans. I encourage you to listen to this pod cast on CBC’s website found here http://www.cbc.ca/quirks/archives/06-07/mar24.html

Rock snot was discovered here less than 10 years ago. Researchers have learned it exists in every river between Red Deer and Waterton and is virtually impossible to kill. The algae has also been found in B.C., Quebec and New Brunswick, as well as parts of the U.S., Scandinavia and New Zealand, the latter of which has lost up to 90% of its fish population in some areas.