[Gordon Dempsey]

Saprolegnia is an opportunistic fungus that will grow on absolutely anything in water, the furry stuff that grows on uneaten fish food in tanks for example is Saprolegnia. It only attacks fish where there is something exposed and unprotected such as, like you said,  slime removal in the case of a Costia infestation or where there has been a physical injury, and cannot attack a healthy fish. The presence of Saprolegnia is therefore a symptom of an ailment but not an ailment in itself. I believe methylene blue may still be a component of current preparations to get rid of it although I do remember malachite green in the dim and distant past and how it stained the silicone in tanks forever!

I am fairly certain that my fish didn't have any Saprolegnia growing on the affected parts which suggests to me that whatever happened happened quickly because a Saprolegnia secondary infection is virtually inevitable when bare flesh is exposed.

[Gordon Dempsey]

This article about UDN makes very interesting reading. Perhaps it is significant that all the affected fish reported so far have been large - the article states that juvenile fish are generally not affected by UDN and also explains the part played by Saprolegnia. There is also a photo in the article that looks a bit familiar.

http://flyfishing.co.uk/news/news/6396-deadly-wild-salmon-disease-found-in-river-spey-fish.html

[Duncan McRae]

Guys

Wish I'd noticed this post earlier.
Had a couple of Trout last night off Ardmurdo and both had a very small patch of fungus on their snouts.They weighed around 2lb and 1lb respectively.Didn't think much of it and returned them.
Last week a couple of Anglers at Ardmurdo had to give up their evening fishing as there was so much raw sewage floating down the water.Presumably from Inverurie sewage plant.
Could this be a factor?

Duncan

[Jim Kerr]

To all

I have had consultation  with  Aberdeen Fish health inspector from Marine Scotland today advising , that if any angler catches a Trout that is on the verge of dyeing or very badly diseased, could they keep the fish alive in their landing net and phone 01330 830080  it can then be collected at the river bank alive if possible.

With Thanks
Jim Kerr
Senior Fishery Officer
Don DSFB

[Rob Brownfield]

It is interesting that there does indeed appear to be an issue with an unidentified disease/bacterial infection, yet the river is still open for angling.

With the close proximity of the Dee, Ythan and Deveron, I would have thought the sensible measure wound be to stop angling, get the problem identified, and then, if not serious, carry on as normal, or if infectious, you have already put in preventative measure.

Yes it would pee people off, but we could have a potential time bomb about to wipe out our rivers, yet we are still allowed to fish. If it proves to be a false alarm, then we have lost a few weeks fishing....