Sea trout stocks

[paul1966]

I am puzzled by the dwindling numbers of seatrout on my local river The Ceddau the reason being the brown trout seem to be holding up well and brown trout as far as I'm aware are the same species as sea trout apart from one migrating to sea. I think this is a general picture on many rivers in west wales and probably the UK.

The environment agency bailiff at our recent AGM said he has spotted very few sea trout redds in the head waters. Is there a difference between a sea trout and a brown trout redds? I didn't think there was.

The only conclusion I can draw is the problem lies out at sea. I know this is the million dollar question but does anyone one have any thoughts on what the problems are? I think this could be one for Paul & John I have just joined the wild trout trust which looks like a really good cause and have a brilliant web site. I haven't had a chance yet to look at it all.

[Paul G]

Hi Paul - you are right that there are a lot of complex things that influence population dynamics of both "resident" and "sea" trout.
It can be things that happen within the river (like changes in how well connected the spawning habitat is to the sea - with changes in barriers/seasonal water levels etc.). There is also a very strong link between the cycles of oceanic plankton productivity and subsequent sea trout condition and survival (in other words years when conditions favour high planktonic productivity, the rest of the food-chain - including predators higher up such as sea trout - have a boom year).

Going on last summer's chronic low flows/dry weather - then there may be an effect on the "passability" of barriers (natural and man-made) on your local river system(s). Additionally, I'm not sure how good the marine plankton populations have been in the last several years...

If it is of interest/help, you can organise an advisory visit for your club (the consultancy/survey work and associated report are free to recipients - paid for by charitable funding. The only cost is a mileage contribution to our nearest conservation officer). Drop me an email on [e-mail] if you are interested in more details/clarification.

Many thanks for your support of the WTT, they are an organisation that I am very happy to work for - definitely hands-on "doers" using the most up to date evidence available.

[paul1966]

Thanks Paul we have done a lot of work to the river mainly through Pembrokeshire Rivers trust www.pembsrt.org/ . I am sure I walked the head waters of the river a number of years ago with someone from the WTT who gave us lots of good advice before we carried out our improvements. This was probably over 12yrs ago. There are always more improvements to be made and the river is in better shape than it was but the sea trout numbers continue to drop. I've fished a great deal last year on one of the stretches that has been improved and it was full of wild brownies which was really pleasing. I've fished the river for 22yrs and in the past we always had good and bad years but for the last 5yrs it's been awful.

I think the problems must be at sea, it would be interesting to see what the planktonic levels have been over the last 20yrs to see if they coincide with our better years.

I am more than happy with the wild brown trout fishing on our river but this isn't enough to satisfy everyone and Pembrokeshire anglers association is really struggling for members due to the lack of sea trout in the river.

I will mention the WTT at our next committee meeting to see if we can arrange another visit from one of your team.

[flatsghost]

Paul
Sad news indeed and a problem all over the UK pretty much. You are not alone with this one!
With sea trout they do not apparently travel the distances at sea that salmon do and tend to stay fairly local. Sand eel netting has had a big effect also and I believe our continental cousins do a lot of this. What great sadness therefore that many end up as fertiliser. The salmon nets/ sea lice issue as highlighted in the sea lochs of Scotland is a massive problem but should not be an issue for your Welsh specimens.
All of PG's comments are valid. This is a complex issue I believe and a very sad one.
Glyn

[paul1966]

Glyn, I'm sure this is another factor it would explain why our very small run of salmon has held up over the years as these head much further out to sea. You can usually see sea trout jumping through-out the winter in the quiet coves around the west wales coast.