Brown trout or sea trout?

Cap'n Fishy

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Yes & none of that bunch had been to sea.

OK, so my question is still...

Why would a fish stay for an extended period in an infertile river until it had struggled to reach the large size of 12 inches, before smolting?

Col
 

cgaines10

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OK, so my question is still...

Why would a fish stay for an extended period in an infertile river until it had struggled to reach the large size of 12 inches, before smolting?

Col

What's to say it struggled to get to 12"? there wasn't only a single fish at that size, there was many in the 10-12" category. We just see it as the norm, maybe it's worth looking into deeper.
 

Cap'n Fishy

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What's to say it struggled to get to 12"?

Well, all life is a struggle, for one thing! 😜

You are saying the river is poor in insect life. You would think, just applying logic, that the more nutrient/fly-life-poor rivers would send their juvenile trout to sea more quickly - when there are still plenty of them at the base of the pyramid of numbers. No? The longer the clock ticks, the more a generation of juveniles is thinned-out by predators. If it is a rich environment, the juveniles might be fast-growing, and it might pay them to put on enough weight to avoid marine predators by being able to delay smolting for a year. However, if life is a struggle, due to poor nutrients/fly life, are the numbers not going to be thinned out too much by waiting until they have attained 12 inches? Would it not be better to smolt when they are numerous and small, rather than few and big?

I dunno? I am just asking questions - but questions that seem reasonable to ask, given what you have said about 12-inch smolts in a nutrient-poor river.

Col
 

cgaines10

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Well, all life is a struggle, for one thing! 😜

You are saying the river is poor in insect life. You would think, just applying logic, that the more nutrient/fly-life-poor rivers would send their juvenile trout to sea more quickly - when there are still plenty of them at the base of the pyramid of numbers. No? The longer the clock ticks, the more a generation of juveniles is thinned-out by predators. If it is a rich environment, the juveniles might be fast-growing, and it might pay them to put on enough weight to avoid marine predators by being able to delay smolting for a year. However, if life is a struggle, due to poor nutrients/fly life, are the numbers not going to be thinned out too much by waiting until they have attained 12 inches? Would it not be better to smolt when they are numerous and small, rather than few and big?

I dunno? I am just asking questions - but questions that seem reasonable to ask, given what you have said about 12-inch smolts in a nutrient-poor river.

Col

I would say it's poor compared to other rivers I know & fish, however I wouldn't say its devoid of fly life. I suppose it's easy for us to try and apply logic, but a migratory fishes life cycle is very complex with a huge amount of issues at each step of the way. I can see where you're coming from though, but I don't know whether it's true or not to whether that is the reason they grow on. I would imagine that other rivers have a similar output to us?

Also there isn't a just a few and big, it's really a mixed bag with huge numbers of smolting typically each year at each size range.

I suppose a question for me would me with regards to the finnock you get in Scotland, how many have actually been to sea? or are they just going through the change and descending through the system.
 

Cap'n Fishy

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I suppose a question for me would me with regards to the finnock you get in Scotland, how many have actually been to sea? or are they just going through the change and descending through the system.

When the finnock come in fresh from the sea, they have sea lice on them. That is half the problem with the fish farms - the amount of sea lice on finnock just grinds them down and kills them.

This is not my photo, but I have witnessed it...



Col
 

cgaines10

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When the finnock come in fresh from the sea, they have sea lice on them. That is half the problem with the fish farms - the amount of sea lice on finnock just grinds them down and kills them.

This is not my photo, but I have witnessed it...



Col

Jesus that's horrendous. I've never seen anything like it on our systems thank god.
 

Cap'n Fishy

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Jesus that's horrendous. I've never seen anything like it on our systems thank god.

Here is a healthy finnock from Loch Hope (north coast - no fish farms close by)...



In a loch where a half pound brownie is a good one, there is not much doubt that wee porker has been in the sea! 😜
 

bobmiddlepoint

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I suppose a question for me would me with regards to the finnock you get in Scotland, how many have actually been to sea? or are they just going through the change and descending through the system.

The answer to that is all of them. Fish that are just going through the change and descending through the system are smolts not finnock!

FWIW every smolt I've ever seen has looked very different to the few overwintered finnock I've seen. For one thing smolts in the spring are well fed little fish and are pretty much in perfect condition with not scale out of place. Finnock that have overwintered in freshwater and are encountered in spring at the same time as smolts are skinny somewhat scruffy things often with missing scales. As Col says finnock encountered in summer have the obvious clue of sea lice. Also finnock smell different to trout or smolts, they somehow smell of the sea.


Andy
 

cgaines10

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The answer to that is all of them. Fish that are just going through the change and descending through the system are smolts not finnock!

FWIW every smolt I've ever seen has looked very different to the few overwintered finnock I've seen. For one thing smolts in the spring are well fed little fish and are pretty much in perfect condition with not scale out of place. Finnock that have overwintered in freshwater and are encountered in spring at the same time as smolts are skinny somewhat scruffy things often with missing scales. As Col says finnock encountered in summer have the obvious clue of sea lice. Also finnock smell different to trout or smolts, they somehow smell of the sea.


Andy

Yes, I know that. I was asking how you decipher that, as I have no reference as we don't seem to get these small finnock that you guys do in Scotland.

Thanks for the info.
 

billy fish

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Ah smolt size...
Chalkstreams and other fertile lowland streams in the Westcountry do produce big smolts. Smolts of 10" are common and bigger are not unknown. I know some of the Welsh rivers produce big (10"+) sea trout smolts. I used to see occasional big smolts on Uist too in May/June.

It is also worth remembering that finnock don't overwinter in all rivers in the same way that they do in many east coast Scottish ones. Certainly in the Westcountry no finnock overwinter in the rivers at all. So in the spring all you see is smolts not finnock, the finnock don't appear until July. You start trout fishing on March 15th and all you get nothing but "brown trout", all the sea trout kelts are long gone out to sea. Then in April you suddenly start to see smolts (as they silver up) turning up all over the rivers. Obviously elsewhere it doesn't happen like this but in many places it does and big (10" - 12") smolts are not considered unusual.


Andy
Having fished West Country rivers for a long time I can verify what Andy is saying about the size of the smolts and the time periods.

Going off topic ,and to my detriment, I wondered why Andy had the Monica “Bobmiddlepoint”. God I’m thick . Got it now.
 

easker1

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we used to get liced fish at Kinlochewe 16miles from the sea, the Brownie pics show the variation we get in our local lochs , some of these were stocked in the 30's from Loch Leven stock,but there all sorts of variations now, lots of highland lochs were stocked like this, , easker1
 

raphael

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When the finnock come in fresh from the sea, they have sea lice on them. That is half the problem with the fish farms - the amount of sea lice on finnock just grinds them down and kills them.
This is not my photo, but I have witnessed it...
Col

You would have seen the ones from the Erriff in 2013... Horrible. Fish that migrated to sea in April/May were back in June, very skinny, bearing tens of parasites on their whole body. The guys from IFI were assuming they were coming back too early, just to escape the lice... but they would probably all die very fast in the river as they were carrying absolutely no reserve of fat and the freshwater system was not able to supply them with food.

R
 

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